We present a music-robotic system capable of performing an accompaniment for a musician and reacting to human performance with gestural and facial expression in real time. This work can be seen as a marriage between social robotics and computer accompaniment systems in order to create more musical, interactive, and engaging performances between humans and machines. We also conduct subjective evaluations on audiences to validate the joint effects of robot expression and automatic accompaniment. Our results show that robot embodiment and expression improve the subjective ratings on automatic accompaniment significantly. Counterintuitively, such improvement does not exist when the machine is performing a fixed sequence and the human musician simply follows the machine. As far as we know, this is the first interactive music performance between a human musician and a humanoid music robot with systematic subjective evaluation.

Rapid localization of injured survivors by rescue teams to prevent death is a major issue. In this paper, a sensor system for human rescue including three different types of sensors, a CO2 sensor, a thermal camera, and a microphone, is proposed. The performance of this system in detecting living victims under the rubble has been tested in a high-fidelity simulated disaster area. Results show that the CO2 sensor is useful to effectively reduce the possible concerned area, while the thermal camera can confirm the correct position of the victim. Moreover, it is believed that the use of microphones in connection with other sensors would be of great benefit for the detection of casualties. In this work, an algorithm to recognize voices or suspected human noise under rubble has also been developed and tested.

Many extant studies proposed various stabilizing control methods for humanoids during the stance phase while hopping and running. Although these methods contribute to stability during hopping and running, humanoid robots do not swing their legs rapidly during the flight phase to prevent rotation in the yaw direction. Humans utilize their torsos and arms when running to compensate for the angular momentum in the yaw direction generated by leg movement during the flight phase. In this study, we developed an angular momentum control method based on human motion for a humanoid upper body. The method involves calculation of the angular momentum generated by the movement of the humanoid legs and calculation of the torso and arm motions required to compensate for the angular momentum of the legs in the yaw direction. We also developed a humanoid upper-body mechanism having human link length and mass properties, using carbon-fiber-reinforced plastic and a symmetric structure for generating large angular momentum. The humanoid robot developed in this study could generate almost the same angular momentum as that of a human. Furthermore, when suspended in midair, the humanoid robot achieved angular momentum compensation in the yaw direction.

The interaction test between a robotic rat and living rat is considered as a possible way to quantitatively characterize the rat sociality. In such robot-rat interactions, the robot should be designed to fully replicate a real rat in terms of morphological and behavioral characteristics. To address this problem, a multi-jointed robot prototype has been modified based on our previous work. We optimally update the forelimb of the robot and redesign the control board to make it more dexterous and increase its behavioral capability. Then, we systematically and kinematically analyze the rotational range of joint variables and the workspace of the robot by using traversal method. To evaluate the motion capability of the modified robot, we propose two quantitative parameters: maximum reachable height (MRH) and minimum bendable distance (MBD). Additionally, we achieve to quantitatively evaluate the behavioral similarity between the robot and rat with the calculated accumulative distance (AD) by using dynamic time warping (DTW). These evaluated methods show high promise to improve the robot-rat interaction to be more similar to rat-rat interaction.

The use of Inertial Measurement Unit (IMU) for gait analysis is gaining popularity because of its advantages of low cost and non-limited workspace. In this context, researchers are focusing on methods for automated data analysis. For example, many algorithms for stride length estimation have been developed. These algorithms rely on event detection to compute gait parameters during walking and on orientation estimation for a more precise double integration of acceleration. However, at the present, there is not comparison between existing algorithms, and the applicability of each algorithm for different walking patterns is not clear. In this paper, we studied the effect on the stride length estimation using three different techniques of event detection and two techniques of orientation estimation, by using an IMU on the lateral side of shank above the ankle. In total 6 patterns of stride estimation algorithms were compared on different walking patterns of normal and brisk walking. We evaluated the techniques in terms of precision, accuracy, and shape of the histogram of the stride estimation error.

Tooth brushing plays an important role in one's health, and particularly, in the prevention of oral diseases. It is a fundamental oral care technique in daily life
however, many elderly or handicapped people cannot brush their teeth without assistance from helpers. The purpose of this study is to develop an automatic teeth cleaning mouthpiece robot. One of the most common methods of brushing teeth is to move the toothbrush along the row of teeth. Hence, a mechanism to wipe teeth using sponges is designed and it consists of an eccentric cam, a wiper with sponges, and a rounded guide rail. This mechanism generates rounded wiper motions along the row of teeth. Furthermore, a safety system is designed to prevent aspiration. Brushing stops automatically when the user lifts his/her jaw up from the jaw supporter.

We developed a small mobile robot in response to the demands in the disaster area. A hybrid locomotion mechanism of wheels and multi-rotors are proposed to realize both high locomotion performance and long-term operation. The wheels allow to highly maneuverable move in a narrow space, and the multi-rotors allow to move to a higher position. The objective of this study is to design the locomotion mechanism and develop a platform for confirming the basic locomotion performance. We attached a wheel mechanism into the assembled hobby drone and embedded an electrical system to operate the robot. The wheels also contribute to protect the multi-rotors from obstacles such as rubble. A stabilizer was proposed to stabilize the robot during running with wheels and designed to allow recover from flipping state. The significant of this work is not only improving the locomotion performance of the drone, but also increase the operating time, this leads various uses at disaster sites. In this paper, the details of the locomotion mechanism and some experimental results using the developed platform are shown.

Humans utilize their torsos and arms while running to compensate for the angular momentum generated by the lower-body movement during the flight phase. To enable this capability in a humanoid robot, the robot should have human-like mass, a center of mass position, and inertial moment of each link. To mimic this characteristic, we developed an angular momentum control method using a humanoid upper body based on human motion. In this method, the angular momentum generated by the movement of the humanoid lower body is calculated, and the torso and arm motions are calculated to compensate for the angular momentum of the lower body. We additionally developed the humanoid upper-body mechanism that mimics the human link length and mass property by using carbon fiber reinforced plastic and a symmetric structure. As a result, the developed humanoid robot could generate almost the same angular momentum as that of human through human-like running motion. Furthermore, when suspended in midair, the humanoid robot produced the angular momentum compensation in the yaw direction.

The receptionist job, consisting in providing useful indications to visitors in a public office, is one possible employment of social robots. The design and the behaviour of robots expected to be integrated in human societies are crucial issues, and they are dependent on the culture and society in which the robot should be deployed. We study the factors that could be used in the design of a receptionist robot in Brazil, a country with a mix of races and considerable gaps in economic and educational level. This inequality results in the presence of functional illiterate people, unable to use reading, writing and numeracy skills. We invited Brazilian people, including a group of functionally illiterate subjects, to interact with two types of receptionists differing in physical appearance (agent v mechanical robot) and in the sound of the voice (human like v mechanical). Results gathered during the interactions point out a preference for the agent, for the human-like voice and a more intense reaction to stimuli by illiterates. These results provide useful indications that should be considered when designing a receptionist robot, as well as insights on the effect of illiteracy in the interaction.

Neuroscientific studies show that humans tend to stabilize their head orientation, while accomplishing a locomotor task. This is beneficial to image stabilization and in general to keep a reference frame for the body. In robotics, too, head stabilization during robot walking provides advantages in robot vision and gaze-guided locomotion. In order to obtain the head movement behaviors found in human walk, it is necessary and sufficient to be able to control the orientation (roll, pitch and yaw) of the head in space. Based on these principles, three controllers have been designed. We developed two classic robotic controllers, an inverse kinematics based controller, an inverse kinematics differential controller and a bio-inspired adaptive controller based on feedback error learning. The controllers use the inertial feedback from a IMU sensor and control neck joints in order to align the head orientation with the global orientation reference. We present the results for the head stabilization controllers, on two sets of experiments, validating the robustness of the proposed control methods. In particular, we focus our analysis on the effectiveness of the bio-inspired adaptive controller against the classic robotic controllers. The first set of experiments, tested on a simulated robot, focused on the controllers response to a set of disturbance frequencies and a step function. The other set of experiments were carried out on the SABIAN robot, where these controllers were implemented in conjunction with a model of the vestibulo-ocular reflex (VOR) and opto-kinetic reflex (OKR). Such a setup permits to compare the performances of the considered head stabilization controllers in conditions which mimic the human stabilization mechanisms composed of the joint effect of VOR, OKR and stabilization of the head. The results show that the bio-inspired adaptive controller is more beneficial for the stabilization of the head in tasks involving a sinusoidal torso disturbance, and it shows comparable performances to the inverse kinematics controller in case of the step response and the locomotion experiments conducted on the real robot.

<p>We are developing a robot for gas pipe inspection, which obtain trust forces by pneumatic actuators. The air pressure to drive them is provided by a compressor, which is set out of the pipe, via tubes. Fictions between these tubes and pipe walls sometimes constrain motions of the robot hardly. Therefore, we developed a tube-sending mechanism, which stays between the compressor and the robot, to support motions of the robot.</p>

<p>A one-legged jumping robot that can mimic the muscular and skeletal system of a human leg is described in this paper. Its height is 1200 [mm], and its total weight is about 9.0 [kg]. The robot is composed of a waist, a thigh, a shin, a foot, and a toe. It has 6 DOFs in total, including 2 DOFs in the hip, 1 DOF in the knee, 2 DOFs in the ankle, and 1 DOF in the toe. Also, a jumping pattern generation algorithm based on the dynamic model of the jumping robot is proposed. The jumping pattern is created generated considering the output ratio of pneumatic actuators and the characteristics of air supply and exhaust. The effectiveness of air supply-exhaust pattern generation algorithm is verified through a jumping experiment.</p>

<p>A human-friendly robot that consists of two arms, a body and a mobile base has been developed. The robot has a collision force suppression mechanism that passively operates without power supply and a control system. The mobile base has four omnidirectional wheels, and is covered by an air cushion bag to absorb collision forces. In this paper, a new passive collision force suppression mechanism capable of being operated by wires is proposed. When a collision between an object and the arm or the body occurs, the collision/contact force is suppressed by the collision force suppression mechanisms. Through collision experiments, the effectiveness of the suppression mechanisms is confirmed.</p>

<p>The KBHR (Kanagawa Biped Humanoid Robot) that is composed of 42 DOFs have been developed. This paper describes a trajectory generation method for 7-DOF manipulators of the KBHR and a robot vision-based object recognition method. The trajectory generation method is based on numerical analysis using Jacobian pseudo-inverse and transpose matrix. In order to recognize objects, an OpenCV image processing library is used. Through an experiment recognizing an object and handing over it to a person, the effectiveness of the trajectory generation algorithm and the object recognition methods is confirmed.</p>

The inertial measurement unit is popularly used as a wearable and flexible tool for human motion tracking. Sensor-to-body alignment, or anatomical calibration (AC), is fundamental to improve accuracy and reliability. Current AC methods either require extra movements or are limited to specific joints. In this research, the authors propose a novel method to achieve AC from standard motion tests (such as walking, or sit-to-stand), and compare the results with the AC obtained from specially designed movements. The proposed method uses the limited acceleration range on medial-lateral direction, and applies principal component analysis to estimate the sagittal plane, while the vertical direction is estimated from acceleration during quiet stance. The results show a good correlation between the two sets of IMUs placed on frontal/back and lateral sides of head, trunk and lower limbs. Moreover, repeatability and convergence were verified. The AC obtained from sit-to-stand and walking achieved similar results as the movements specifically designed for upper and lower body AC, respectively, except for the feet. Therefore, the experiments without AC performed can be recovered through post-processing on the walking and sit-to-stand data. Moreover, extra movements for AC can be avoided during the experiment and instead achieved through the proposed method.

The authors are developing anthropomorphic musical performance robots as an approach to understand the human motor control and to enhance the human-robot interaction from an engineering point of view. For this purpose; since 1990, we have developed an anthropomorphic flutist robot. As one of our long-term approaches, we aim to develop an anthropomorphic musical performance robot capable of playing different kinds of woodwind instruments, e.g. flute and saxophone. In this paper, the improvements of the mechanical design and sensing system of the Waseda Flutist Robot No. 4 Refined V (WF-4RV) are detailed. As for the sensing system, an array of sensors has been designed to detect the lip's pressure distribution. On the other hand, the lips and lung have been re-designed to enable the flutist robot to play the saxophone. (C) 2016 Elsevier B.V. All rights reserved.

The study of human nonverbal social behaviors has taken a more quantitative and computational approach in recent years due to the development of smart interfaces and virtual agents or robots able to interact socially. One of the most interesting nonverbal social behaviors, producing a characteristic vocal signal, is laughing. Laughter is produced in several different situations: in response to external physical, cognitive, or emotional stimuli
to negotiate social interactions
and also, pathologically, as a consequence of neural damage. For this reason, laughter has attracted researchers from many disciplines. A consequence of this multidisciplinarity is the absence of a holistic vision of this complex behavior: the methods of analysis and classification of laughter, as well as the terminology used, are heterogeneous
the findings sometimes contradictory and poorly documented. This survey aims at collecting and presenting objective measurement methods and results from a variety of different studies in different fields, to contribute to build a unified model and taxonomy of laughter. This could be successfully used for advances in several fields, from artificial intelligence and human-robot interaction to medicine and psychiatry.

The implementation of strategies for intuitive and natural communication between robots and humans, depending on the specific situation, is becoming more and more important. Intuitive and human-like communication patterns for human-robot cooperation will ease communication cognitive load and allow the user to better focus on the task at hand. This work presents a basic facial expression system for a humanoid robot saxophonist, allowing the robot to change its expression during a musical performance to both send specific cues for synchronization to a partner human player, and also add emotional emphasis to the performance, as human players naturally do.

Humanoid robots are expected to be able to communicate with humans using physical interaction, including hug, which is a common gesture of affection. In order to achieve that, their physical embodiment has to be carefully planned, as a user-friendly design will facilitate interaction and minimise repulsion. In this paper, we investigate the effect of manipulating the visual/tactile appearance of a robot, covering wires and metallic parts with clothes, and the auditory effect by enabling or disabling the connector of the hand. The experiment consists in a hugging interaction between the participants and the humanoid robot ARMAR-IIIb. Results after participation of 24 subjects confirm the positive effect from using clothes to modify the appearance and the negative effect of noise and vibration.

this paper describes a kinematic model of Support robot for elder people. This support robot can help elders who do not have enough physical strength on the lower limbs during sit to stand due to aging. It also follows the natural pattern of human motion during sit to stand. Several experiments were carried out using optotrack to measure the human motion posture while sit to stand motion in addition to estimate the required trajectory for support robot during assisting. Computer program was developed to evaluate the variables of the support robot with the sit to stand trajectory.

One Leg Stance (OLS), a test assessing postural stability, is popularly conducted both in clinic and community settings because it is inexpensive and time-efficient. However, the evaluation based on visual observation and manual time measurement with a stop-watch cannot provide quantitative and detailed parameters for longitudinal or cross-sectional studies. In recent years, to overcome these limitations, the use of Inertial Measurement Unit (IMU) as objective measurement analysis tools is becoming more and more popular. However, the greatest issue is that IMU data segmentation is still time-consuming and prone to errors, as the OLS segmentation is being done manually, off-line, on recorded data. In this paper we proposed a novel algorithm for the automatic segmentation of IMU data of the OLS test. The result showed that the correct rate of detection was over 90% which was close to the correct rate in manual segmentation. Compared to manual segmentation with video, besides being less time-consuming, the proposed algorithm closes the loop making the data acquisition and analysis completely automatic, thus can be integrated in self-assessment smart phone applications, allowing the continuous tracking of postural stability also outside clinics and health-care facilities.

Nowadays, with the development of the proportion of the elderly population in the world, several problems caused by the population aging gradually into people's horizons. One of the biggest problems plagued the vast majority of the elderly is hemiplegia, which leads to the vigorous development of the physical therapists. However, these traditional methods of physical therapy mainly rely on the skill of the physical therapists. In order to make up the defects of traditional methods, many research groups have developed different kinds of robots for lower limb rehabilitation training but most of them can only realize passive training which cannot adopt rehabilitation training based on the patients' individual condition effectively and they do not have a rehabilitation evaluation system to assess the real time training condition of the hemiplegic patients effectively. In order to solve the problems above, this paper proposed a lower limb rehabilitation evaluation system which is based on the virtual reality technology. This system has an easy observation of the human-computer interaction interface and the doctor is able to adjust the rehabilitation training direct at different patients in different rehabilitation stage based on this lower limb rehabilitation evaluation system. Compared with current techniques, this novel lower limb rehabilitation evaluation system is expected to have significant impacts in medical rehabilitation robot field.

The objective of this study was to design a new model of wheel shape for increasing climbing ability of slopes and steps. We made a new model using a statics for calculating the ability easily and found that the arc-shaped notch type seems to be the best and implemented to our robot. In this paper, we introduce the detail of the proposed model and simulation results.

This paper describes the mechanism of a one-legged jumping robot that can mimic the muscular and skeletal system of a human leg. The jumping robot has a waist, a thigh, a shin, a foot, and a toe. The McKibben-type pneumatic muscle actuators that are able to generate the maximum output force of 1200 [N] are employed. Two kinds of pneumatic artificial muscles, mono-articular and bi-articular muscles, were installed in the rear and in the front of the thigh and shin. A jumping pattern is also developed in consideration of the performance of the pneumatic actuators. Several jumping experiments were conducted, and the effectiveness of the mechanism and jumping pattern was verified.

This paper describes the mechanism of a human-friendly robot. The robot consists of two arms, a body and a mobile base. An air cushion bag is developed to cover the entire exterior of the robot. It can reduce the generated impact forces in a collision between any part of the robot and a human. A passive collision suppression mechanism is also developed to deal with greater impact forces. The suppression mechanism is installed in the pitch axis of the elbow and the yaw axis of the waist. The base consists of four omnidirectional wheels, enabling movement in any direction. Moreover, the control method for the base is discussed in this study. Using the robot, collision experiments are conducted and the effectiveness of the robot mechanism and the control method is verified.

Automatic and objective detection algorithms for gait events from MEMS Inertial Measurement Units data have been developed to overcome subjective inaccuracy in traditional visual observation. Their accuracy and sensitivity have been verified with healthy older adults, Parkinson's disease and spinal injured patients, using single-task gait exercises, where events are precise as the subject is focusing only on walking. Multi-task walking instead simulates a more realisitc and challenging scenario where subjects perform secondary cognitive task while walking, so it is a better benchmark. In this paper, we test two algorithms based on shank and foot angular velocity data in single-task, dual-task and multi-task walking. Results show that both algorithms fail when the subject slows extremely down or pauses due to high cognitive and attentional load, and, in particular, the first stride detection error rate of the foot-based algorithm increases. Stride time is accurate with both algorithms regardless of walking types, but the shank-based algorithm leads to an overestimation on the proportion of swing phase in one gait cycle. Increasing the number of cognitive tasks also causes this error with both algorithms.

This paper introduces a motion planning method to generate ladder climbing motion for a four-limbed robot. This method contains the following points: (1) independent planning of path and time in 3 dimensional space for trajectory planning; (2) path length minimization according to given midpoints. In trajectory planning, arc-length parameterization is used to separate path planning and time planning so that they can be done independently. After path is planned, time planning along the planned path can be given freely to meet our requirement, such as speed and acceleration adjustment for the protection of motors, optimization for dynamics analysis, dynamic obstacle avoidance and so on. Results from simulations and experiments authenticate the validity of our motion generation method.

In this paper we tackle the problem of visually predicting surface friction for environments with diverse surfaces, and integrating this knowledge into biped robot locomotion planning. The problem is essential for autonomous robot locomotion since diverse surfaces with varying friction abound in the real world, from wood to ceramic tiles, grass or ice, which may cause difficulties or huge energy costs for robot locomotion if not considered. We propose to estimate friction and its uncertainty from visual estimation of material classes using convolutional neural networks, together with probability distribution functions of friction associated with each material. We then robustly integrate the friction predictions into a hierarchical (footstep and full-body) planning method using chance constraints, and optimize the same trajectory costs at both levels of the planning method for consistency. Our solution achieves fully autonomous perception and locomotion on slippery terrain, which considers not only friction and its uncertainty, but also collision, stability and trajectory cost. We show promising friction prediction results in real pictures of outdoor scenarios, and planning experiments on a real robot facing surfaces with different friction.

Friction estimation from vision is an important problem for robot locomotion through contact. The problem is challenging due to its dependence on many factors such as material, surface conditions and contact area.
In this paper we 1) conduct an analysis of image features that correlate with humans' friction judgements; and 2) compare algorithmic to human performance at the task of predicting the coefficient of friction between different surfaces and a robot's foot. The analysis is based on two new datasets which we make publicly available. One is annotated with human judgements of friction, illumination, material and texture; the other is annotated with static coefficient of friction (COF) of a robot's foot and human judgements of friction. We propose and evaluate visual friction prediction methods based on image features, material class and text mining. And finally, we make conclusions regarding the robustness to COF uncertainty which is necessary by control and planning algorithms; the low performance of humans at the task when compared to simple predictors based on material label; and the promising use of text mining to estimate friction from vision.

Crawling motion by a robot is effective for reducing shock in the case of a fall. It thus decreases the possibility of a locomotion malfunction on uneven terrain. In this paper, the control of crawling motion on uneven terrain is described. Firstly, crawling motion and detailed motion are explained. Then, a method for controlling crawling motion is outlined for its realization. To verify the effectiveness of the proposed method for locomotion on uneven terrain, rough rubble ground was generated in a dynamics simulator and the crawling method was applied to our developed four-limbed robot. Additionally, a crawler robot was generated. A comparison was conducted to verify the difference in locomotion capabilities between the proposed method and other locomotion styles. The simulation results confirmed that the proposed method enabled successful locomotion of our four-limbed robot on uneven terrain.

In this paper, we describe an intraoral pressure control system for the humanoid saxophone-playing robot WAS-4. We studied the model for air flow control in a wind instrument, and via a series of assessment tests to analyze the robot performance, we discovered that the control of the intraoral pressure of the robot is critical for continuous sound production. We then developed a control system to maintain the intraoral pressure stable during note sustaining and changing, preserving reed vibration and sound production. We assessed the effectiveness of the system via a final evaluation experiment.

The demand for monitoring from high points is increasing to support remote control and accurate monitoring. Unmanned ground vehicles with long arms are used to achieve long-term and accurate monitoring. The use of convex steel tapes is effective for achieving both high strength and lightness of the arm, which prevents the robot from collapsing or the arm from falling off. However, the previously proposed methods could not be used under tough environmental conditions such as strong winds as well as when the posture of the robot is changed. The objective of the present study is to design a novel extendable arm structure using convex tapes for outdoor usage. We designed an arm with a novel combination of convex tapes that can endure outdoor interferences. We manufactured the arm using a new method such that there is no need to separate the convex tapes. Our results indicated that the robot could extend its arm up to 4 m at a wind speed of 10 m/s and its posture can be changed to 15 degrees in all directions without the use of additional supports such as an outrigger. This novel arm is useful for supporting remote-controlled aerial work platform outdoors such as in a disaster struck area where only tiny mobile robots can enter. This novel combination method is significant not only because it fills the gap in previous sutures but also because it does not require complex mechanisms such as the outrigger method.

Current training for laparoscopy focuses only on the enhancement of manual skill and does not give advice on improving trainees' posture. However, a poor posture can result in increased static muscle loading, faster fatigue, and impaired psychomotor task performance. In this paper, the authors propose a method, named subliminal persuasion, which gives the trainee real-time advice for correcting the upper limb posture during laparoscopic training like the expert but leads to a lower increment in the workload.
A 9-axis inertial measurement unit was used to compute the upper limb posture, and a Detection Reaction Time device was developed and used to measure the workload. A monitor displayed not only images from laparoscope, but also a visual stimulus, a transparent red cross superimposed to the laparoscopic images, when the trainee had incorrect upper limb posture. One group was exposed, when their posture was not correct during training, to a short (about 33 ms) subliminal visual stimulus. The control group instead was exposed to longer (about 660 ms) supraliminal visual stimuli.
We found that subliminal visual stimulation is a valid method to improve trainees' upper limb posture during laparoscopic training. Moreover, the additional workload required for subconscious processing of subliminal visual stimuli is less than the one required for supraliminal visual stimuli, which is processed instead at the conscious level.
We propose subliminal persuasion as a method to give subconscious real-time stimuli to improve upper limb posture during laparoscopic training. Its effectiveness and efficiency were confirmed against supraliminal stimuli transmitted at the conscious level: Subliminal persuasion improved upper limb posture of trainees, with a smaller increase on the overall workload.

© 2015 IEEE. In the near future, robots are expected to perform assistive tasks and do different kind of jobs. In particular, humanoid robots are possible candidates for being used as helpers in activities of daily living. One possible employment is working as a receptionist, providing useful indications to visitors in a public office. The design of how robots could look like is a matter of growing importance, as it is important to create a look that poses no uncanny valley effects on the human user and that is appropriate to potentially serve in different job areas in human society. In this paper we want to describe the study on anthropomorphism of a receptionist robot. We invited Brazilian people with different education levels to interact with two variations of a receptionist robot, different in physical appearance as well as in the sound of the voice. In one case, the appearance was a conversational agent made with computer graphics, in the other, a real humanoid robot. Results gathered from surveys and comments of the participants provide useful directions to design a receptionist robot and insights on the effect of digital divide on anthropomorphism.

© 2015 IOP Publishing Ltd. In this paper, we study the behavioral response of rats to a robotic rat during multi-rat interaction. Experiments are conducted in an open-field where a robotic rat called WR-5 is put together with three laboratory rats. WR-5 is following one rat (target), while avoiding the other two rats (outside observers) during interaction. The behavioral characteristics of each target rat is evaluated by scoring its locomotor activity and frequencies of performing rearing, body grooming and mounting actions. Additionally, the frequency of being mounted by other rats is also measured. Experimental results show that the target becomes more active after interaction. The rat species, with more active behavioral characteristics, is more susceptible to being adjusted by the robot. The increased time spent by the outside observers in the vicinity of the robot indicates that a biomimetic robot has the promise for modulating rat behavior even without direct interaction. Thus, this study provide a novel approach to shaping the sociality of animals living in groups.

An online walking pattern generation is important for a biped humanoid robot to move in dynamic environments. This chapter describes a novel online walking pattern generation using Fast Fourier Transform (FFT). Most previous studies about online walking pattern generation use an inverted pendulum model, which requires other methods to compensate for errors between the model and a real robot. Because our method uses a multi-body robot model, a biped robot can dynamically change its motions online by utilizing only the proposed method. If a robot has external sensors such as a stereo vision system to recognize dynamic environments, the robot can follow a moving target. Verification of the proposed method is conducted through experiments with the human-sized humanoid robots WABIAN-2R and KOBIAN.

Laughter is a very interesting non-verbal human vocalization. It is classified as a semi voluntary behavior despite being a direct form of social interaction, and can be elicited by a variety of very different stimuli, both cognitive and physical. Automatic laughter detection, analysis and classification will boost progress in affective computing, leading to the development of more natural human-machine communication interfaces. Surface Electromyography (sEMG) on abdominal muscles or invasive EMG on the larynx show potential in this direction, but these kinds of EMG-based sensing systems cannot be used in ecological settings due to their size, lack of reusability and uncomfortable setup. For this reason, they cannot be easily used for natural detection and measurement of a volatile social behavior like laughter in a variety of different situations. We propose the use of miniaturized, wireless, dry-electrode sEMG sensors on the neck for the detection and analysis of laughter. Even if with this solution the activation of specific larynx muscles cannot be precisely measured, it is possible to detect different EMG patterns related to larynx function. In addition, integrating sEMG analysis on a multisensory compact system positioned on the neck would improve the overall robustness of the whole sensing system, enabling the synchronized measure of different characteristics of laughter, like vocal production, head movement or facial expression; being at the same time less intrusive, as the neck is normally more accessible than abdominal muscles. In this paper, we report laughter discrimination rate obtained with our system depending on different conditions.

Ankle rehabilitation training takes an important role in the hemiplegic rehabilitation training. Traditional training requires the physical therapist treating the patient as one to one. The training process is repeating and needs a long period. The performances of training rely heavily on the skill of therapists. The training effectiveness depends on the skills of the therapist. To improve the training effectiveness, there are many ankle rehabilitation robots are proposed. However all of them are only focusing on providing a passive training to the patient. In this paper, an ankle rehabilitation robot with three degrees is proposed. This robot can not only realizes the passive training but also has much more sensors to detect the movements of the ankle, especially realizes the patient active training. In this paper, the detail design of the mechanism is introduced. The mechanical structure includes pedal parts, thigh fixing parts, cross slider parts, driving unit and sensing unit. Comparing with current ankle rehabilitation researches, this robot uses linear motion in horizontal and vertical plane instead of rotary motion to realize dorsiflexion/plantar flexion and abduction/adduction. Finally, we present ankle motion space analysis and ankle robot workspace analysis of ankle robot to verify the feasibility of the robot.

Oral presentation is considered as one of the most sought after skills by companies and professional organizations and program accreditation agencies. However, both learning process and evaluation of this skill are time demanding and complex tasks that need dedication and experience. Furthermore, the role of the instructor is fundamental during the presentation assessment. The instructor needs to consider several verbal and nonverbal communications cues sent in parallel and this kind of evaluation is often subjective. Even if there are oral presentation rubrics that try to standardize the evaluation, they are not an optimal solution because they do not provide the presenter a real-time feedback. In this paper, we describe a system for behavioral monitoring during presentations. We propose an ecological measurement system based on Inertial Measurement Units to evaluate objectively the presenter's posture through objective parameters. The system can be used to provide a real-time feedback to the presenters unobtrusively.

Up to now, the number of hemiplegia rehabilitation devices is increasing quickly. But most of ankle rehabilitation training just limit to the training of patients' affected side. They ignore the importance of patients' subjective participation in the recovery of central nervous system. In our new research, we proposed a new method that making use of the movements of the sound side to realize the passive training of the affected side. Therefore, an ankle motion detecting mechanism is proposed to detect the ankle motion of patients' sound side. In this paper, we will introduce the detail design of the mechanism. It includes three detecting units for recording the rotations of ankle. Comparing with other Body-movement information detection method, such as optical measurement method and biological signals measuring method, it can gather the real-time information of three rotations of ankle with a simple structure. This ankle motion detecting mechanism can not only detects the ankle motion but also helps patients do affected ankle strength training. Finally, the workspace analysis of this detecting mechanism is carried out to verify the ability of the designed mechanism.

Robots are possible candidates for performing tasks as helpers in activities of daily living in the future: working as a receptionist is one possible employment. However, the way the receptionist robot should appear, sound and behave needs to be investigated carefully, in order to design a robot which is accepted and perceived in a positive way by common users. This paper describes a study on anthropomorphism of a receptionist robot made for Brazilian people depending on the appearance and on the voice of the receptionist. This experiment was preceded by a preliminary survey about expectation of people regarding receptionists. The main experiment consisted in having Brazilian people interacting with a conversational agent and with a humanoid robot through a video conference. The two receptionists are not only different in physical appearance, but in the sound of the voice, too, which can be either human-like or robotic sound. The two receptionists gave indications to the participants to reach rooms where they could evaluate the receptionists through questionnaires concerning anthropomorphism and uncanniness among other concepts. The results gathered from both experiments provide useful hints to design a receptionist robot.

Environment recognition is an effective way for a mobile robot to move across rough terrain. In particular, this makes it possible to prevent a tiny mobile robot from getting stuck or turning over. Several studies have been conducted on environment recognition using a laser range finder or camera. However, almost all of these studies focused on obstacle detection or shape recognition, which cannot be used to recognize the surface condition such as slipperiness. The purpose of this work is to design a model for estimating the surface condition using a tiny mobile robot. We set slipperiness as one of the parameters for recognizing the surface condition, which is already used by terramechanics, along with two additional parameters, the hardness and unevenness. We find that a robot can roughly estimate the ground hardness by measuring the current peak of a motor and the unevenness from measuring the robot posture. By recognizing the surface condition, the robot can change the parameters of the controlling motor based on the ground characteristics. This new method for recognizing the surface condition is significant, not only because it fills gaps in the previous research, but also because it does not require any special sensors such as a laser range finder and does not consume a large quantity of energy. Therefore, it achieves a core objective of our environmental monitoring system using multiple mobile robot.

The Uncanny valley hypothesis, which tells us that almost-human characteristics in a robot or a device could cause uneasiness in human observers, is an important research theme in the Human Robot Interaction (HRI) field. Yet, that phenomenon is still not well-understood. Many have investigated the external design of humanoid robot faces and bodies but only a few studies have focused on the influence of robot movements on our perception and feelings of the Uncanny valley. Moreover, no research has investigated the possible relation between our uneasiness feeling and whether or not we would accept robots having a job in an office, a hospital or elsewhere. To better understand the Uncanny valley, we explore several factors which might have an influence on our perception of robots, be it related to the subjects, such as culture or attitude toward robots, or related to the robot such as emotions and emotional intensity displayed in its motion. We asked 69 subjects (N = 69) to rate the motions of a humanoid robot (Perceived Humanity, Eeriness, and Attractiveness) and state where they would rather see the robot performing a task. Our results suggest that, among the factors we chose to test, the attitude toward robots is the main influence on the perception of the robot related to the Uncanny valley. Robot occupation acceptability was affected only by Attractiveness, mitigating any Uncanny valley effect. We discuss the implications of these findings for the Uncanny valley and the acceptability of a robotic worker in our society.

Waseda University has researched on biped robots since 1967. This paper describes our latest biped robots: (i) WABIAN-2, (ii) a biped running robot, and (iii) WL-16. WABIAN-2 is a biped humanoid robot and has realized a human-like walk with the knees stretched by utilizing a 2-DOF waist mimicking a human's pelvis motion. We are developing a new biped humanoid robot which can jump by utilizing a pelvic movement and leg elasticity. WL-16 is a human-carrying biped vehicle.

Energy consumption and stability are two important problems for humanoid robots deployed in remote outdoor locations. In this paper we propose an extended footstep planning method to optimize energy consumption while considering motion feasibility and ground friction constraints. To do this we estimate models of energy, feasibility and slippage in physics simulation, and integrate them into a hybrid A* search and optimization-based planner. The graph search is done in footstep position space, while timing (leg swing and double support times) and COM motion (parameterized height trajectory) are obtained by solving an optimization problem at each node. We conducted experiments to validate the obtained energy model on the real robot, as well as planning experiments showing 9 to 19% energy savings. In example scenarios, the robot can correctly plan to optimally traverse slippery patches or avoid them depending on their size and friction; and uses stairs with the most beneficial dimensions in terms of energy consumption.

Analysis of human running has revealed that the motion of the human leg can be modeled by a compression spring because the leg's joints behave like a torsion spring in the stance phase. Moreover, the knee bends rapidly to avoid contact of the foot with the ground in the swing phase. In this paper, we describe the development of a knee joint mechanism that mimics the elastic characteristics of the stance leg and rapid bending knee of the idling leg of a running human. The knee was equipped with a mechanism comprising two leaf springs and a worm gear for adjusting the joint stiffness and high-speed bending knee. Using this mechanism, we were able to achieve joint stiffness within the range of human knee joints that could be adjusted by varying the effective length of one of the leaf springs. In addition, the mechanism was able to bend rapidly by changing the angle between the two leaf springs. The equation proposed for calculating the joint stiffness considers the difference between the position of the fixed point of the leaf spring and the position of the rotational center of the joint. We evaluated the performance of the adjustable joint stiffness and the effectiveness of the proposed equation for joint stiffness and high-speed knee bending. We were able to make a bipedal robot hop using pelvic oscillation for storing energy produced by the resonance to leg elasticity and confirmed the mechanism could produce large torque 210 Nm.

Human running motion can be modeled using a spring-loaded inverted pendulum (SLIP), where the linear-spring-like motion of the standing leg is produced by the joint stiffness of the knee and ankle. To use running speed control in the SLIP model, we should only decide the landing placement of the leg. However, for using running speed control with a multi-joint leg, we should also decide the joint angle and joint stiffness of the standing leg because these affect the direction of the ground reaction force. In this study, we develop a running control method for a human-like multi-joint leg. To achieve a running motion, we developed a running control method including pelvis oscillation control for attaining jumping power with the joint stiffness of the leg and running speed control by changing the landing placement of the leg. For using running speed control, we estimated the ground reaction force using the equation of motion and detected the joint angles of the leg for directing the ground reaction force toward the center of mass. To evaluate the proposed control methods, we compared the estimated ground reaction force with the force measured by the real robot. Moreover, we performed a running experiment with the developed running robot. By using ground reaction force estimation, this robot could accomplish the running motion with pelvic oscillation for attaining jumping power and running speed control.

(Early Access Articles)

This study aims to develop a state transition model and speech recognition module for application to a whole-body patient simulator for scenario based training (SBT) of neurological examination procedures. These procedures are very important for the early identification of neurological system disorders. In neurological examinations, the doctor selects procedures by situation of patients, interacts with the patient and performs a series of medical procedures to judge the site of nerve disorders and lesions. SBT is one type of training that doctor performs to be based on scenario. Scenario is patient situation and examination procedure. SBT is used for the training of such examinations. SBT is often performed using simulated patients (SPs); however, the number of SPs is not sufficient and SPs cannot adequately reproduce diseases. Therefore, we integrated a state transition model with a commercial speech recognition software and developed a dialogue system for SBT. First, we customized the grammatical rules and the different words that the software can recognize. By doing so, the recognition rate improved to about 90%. Second, we developed a probability model for the state transition model. In neurological examinations, patient pause is limited and an order of procedures is generally decided. We developed a state transition model including probability model with the customized speech recognition module.

Neurologic examination takes an important role in the physical examination. By now, several methods have been carried out for medical training which bring the benefits for trainee to master the skills and accumulate experiences. However, because of the limits of these methods, the training effectiveness is limited. With the developments of technology, more and more simulators have been launched to improve medical training effectiveness. However, most of these simulators only focus on mimicking the symptoms, not simulating the pathology of diseases. In this paper, we propose an improved motor nerve model which is used in the elbow robot named WKE-2(Waseda Kyotokagaku Elbow Robot No.2). This robot is designed to simulate the disorders of motor nerves to give the trainee a full training on the elbow examination. The motor nerve model mimics the real motor nerve structure. And the functions of each part are designed from analysis of the real functions of each organ. In this robot, the effects of motor nerve system, and various symptoms related to the examination of elbow force, biceps tendon reflex, involuntary action are simulated. Making use of this robot, a systematic training on the skills as well as the understanding of knowledge is provided. Finally, several experiments are performed to verify our proposed system. The experimental results lead to the consideration that the approach is worth following in further research.

Decreasing balance ability in older adults increases the risk of falls. According to the literature, two balance strategies are revealed, ankle strategy and hip strategy. The aim of this paper is to study the postural stability of the one leg stance on the frontal plane and verify the strategy used in older adults. A hypothesis about two different patterns in hip strategy is made and experiments were conducted with 80 healthy elderly subjects. The posture is captured by Waseda Bioinstrumentation -4 Rev Inertial Measurement Unit (WB-4R IMU). The preliminary analysis shows the dominant pattern is moving the upper body in a lateral direction when losing balance on frontal plane.

In human-robot interaction, it is important for the robots to adapt to our ways of communication. As humans, rules of non-verbal communication, including greetings, change depending on our culture. Social robots should adapt to these specific differences in order to communicate effectively, as a correct way of approaching often results into better acceptance of the robot. In this study, a novel greeting gesture selection system is presented and an experiment is run using the robot ARMAR-IIIb. The robot performs greeting gestures appropriate to Japanese culture; after interacting with German participants, the selection should become appropriate to German culture. Results show that the mapping of gesture selection evolves successfully.

This paper describes a robotic hand that attaches to the wrist of a biped humanoid robot capable of mimicking a human motion. The robotic hand has five tendon-driven fingers that consist of a thumb, and an index, a middle, a ring, and a little finger. The fingers are composed of a V-grooved pulley, an E-type retaining ring, a hinge pin, and a torsional spring. The thumb has two motors for rolling and yawing motions and the other fingers have one motor for rolling motions. The effectiveness of the robot hands is confirmed through many grasping experiments.

Cranial nerve examination takes an important role in the physical examination. All the medical staffs need to be trained to master the skills for examination. By now, several training methods have been carried out for medical training including training with the simulated patient (SP). However, considering the characters of eyeball, the involuntary actions cannot be simulated by Sp. With the developments of technology, more and more robot heads have been launched. However, these simulators only focus on mimicking the healthy human abilities, not simulating disorders for medical training. In this paper, we propose a novel eyeball motion nerve model which is used in the head robot named WKH-2(Waseda Kyotokagaku Head Robot No. 2). This robot is designed to simulate the disorders of eyeball movements to give the trainee a full training on cranial examination. The motor nerve model is carried out from mimicking the real eyeball nerve structure. And the functions of each part are designed from analysis of the real functions of each organ. In this robot, the effects of eyeball motion nerve system, and various symptoms are simulated. Making use of this robot, a systematic training on the skills as well as the understanding of medical knowledge is provided. Finally, several experiments are carried out to verify our proposed system. The experimental results show that the approach is worth following in further research.

The falling of a biped humanoid robot is treated as an extremely unstable state. When an unexpected fall happens, it may cause serious damage to both the robot itself. This study focuses on the falling issue and investigates the effect of the "torso protective strategy" for safe landing of a biped humanoid robot. First, the effectiveness of the torso strategies to the safe landing is analyzed from an energy variation perspective of the robot system. The torso strategies are used to do negative work that reduced the energy of the robot system, thereby reducing the impact velocity of the robot. Then, a comparative simulation is made on a model of humanoid robot to validate the influence of the torso strategies on safe landing.

We propose a new heel-contact toe-off walking model based on the Linear Inverted Pendulum (LIP) model, which due to the linearity and the ease of manipulation of the equations, could be considered to be advantageous for a future online implementation for the generation of walking patterns. This new model is based on the so called functional rockers of the foot (heel, ankle and forefoot rockers), each of which are modeled as an inverted pendulum, changing the ground contact point position of the inverted pendulums for each rocker. We focus on the motion of the Center of Mass (CoM) in the sagittal plane, as it is the plane on which the rockers take place, but also generate the motions on the frontal plane. The model proved to work for constant velocity, accelerating and decelerating gaits, and the effects of the change of pivot point during heel-contact toe-off could be corroborated in the Zero Moment Point (ZMP) graphs. The implementation of this model could improve the human likeness of the motions, as well as the stability of the locomotion.

While robots are often used in autism therapy, the Uncanny valley effect was never studied in subjects with Autistic Spectrum Disorder (ASD). Since persons with ASD have trouble understanding body language, they react differently to the Uncanny valley. In this paper, we propose to investigate the possible difference in the Uncanny valley's perception of an emotional humanoid robot in subjects with ASD and subjects without ASD. Thirty four adult participants (N = 34, control: 19, ASD: 15; age: 28.5) were asked to watch videos of an emotional humanoid robot and rate its emotions and its gait (Perceived Humanness, Eeriness and Attractiveness). We have found differences between the two groups in their perception of the robot's Perceived Humanness (p &lt; .05). Also, while the ASD group performed as well as the control group for emotion recognition task, we found that the ASD group is more sensible to the Uncanny valley effects than the control group. Finally we conclude on what our findings bring to the Human Robot Interaction field.

This paper describes a walking stabilization control for a biped humanoid robot with narrow feet. Most humanoid robots have larger feet than human beings to maintain their stability during walking. If robot's feet are as narrow as humans, it is difficult to realize a stable walk by using conventional stabilization controls. The proposed control modifies a foot placement according to the robot's attitude angle. If a robot tends to fall down, a foot angle is modified about the roll axis so that a swing foot contacts the ground horizontally. And a foot-landing point is also changed laterally to inhibit the robot from falling to the outside. To reduce a foot-landing impact, a virtual compliance control is applied to the vertical axis and the roll and pitch axes of the foot. Verification of the proposed method is conducted through experiments with a biped humanoid robot WABIAN-2R. WABIAN-2R realized a knee-bended walking with 30 mm breadth feet. Moreover, WABIAN-2R mounted on a human-like foot mechanism mimicking a human's foot arch structure realized a stable walking with the knee-stretched, heel-contact, and toe-off motion.

In the past we achieved to use a rat-like robot and a single rat to develop Animal Models of Mental Disorder (AMMDs) through stress exposure. However, to simulate the real social environment, we use a rat-like robot composed of multiple links to chase a specific rat (target) in a group of rats (outside observers). In this paper, we aim to develop a real-time control system for a multi-link robot surrounded by multiple rats. A virtual impedance model was adopted to generate posture and trajectory for a multi-link robot named WR-5. With the analysis of virtual forces/moments acting on WR-5 based on the model, corresponding dynamic equations can be obtained to control the motion of WR-5. Simulation results show that the head of WR-5 can accurately direct a target object in the following test. After conducting experiments with three rat subjects (a target rat, two outside observers), the output results suggest that the head and body gesture of WR-5 achieves to follow the target in real-time. Meanwhile, the control system allows real-time avoidance of the moving outside observers during interaction.

This paper describes the bipedal humanoid robot that makes human laugh with its whole body expression and affect human's psychological state. In order to realize "Social interaction" between human and robot, the robot has to affect human's psychological state actively. We focused on "laugh" because it can be thought as a typical example for researching "Social interaction". Looking through a Japanese comedy style called "manzai" or the art of conversation, we picked out several methods for making human laugh. Then we made several skits with the advice of comedians, and made the whole body humanoid robot perform them. Results of experimental evaluation with these skits shows that the robot's behavior made subjects laugh and change their psychological state seen as a decrease of "Depression" and "Anger".

The design of what a robot could look like is a matter of growing importance. Variations of style, size, shape and colour open endless design possibilities. It is important to create a look that poses no visual uncanny valley effects on the human user and that is appropriate to potentially serve in different job areas in human society. In this paper we want to share the methods applied in the design of a new head for the humanoid robot KOBIAN-R. Our creation process is similar to that of the product design process taking into account the psychology of shape, colour and functionality to name a few. Following the creative process we conducted some surveys to assess our new design. Feedback data from participants from a diverse age range and cultural backgrounds are a precious input towards the future development of this robotic head.

Human running motion can be modeled by a spring loaded inverted pendulum (SLIP). However, this model, despite being widely used in robotics, does not include human-like pelvic motion. In this study, we show that the pelvis actually contributes to the increase in jumping force and absorption of landing impact, both of which findings can be used to improve running robots. On the basis of the analysis of human running motion, we propose a new model named SLIP 2 (spring loaded inverted pendulum using pelvis). This model is composed of a body mass, a pelvis, and leg springs; the model can control its springs during running by use of pelvic movement in the frontal plane. To achieve hopping and running motions, we developed pelvis oscillation control, running velocity control, and stabilization control using an upper body, as control methods. We also developed a new hopping robot using the SLIP 2 model. To evaluate the proposed model and control methods, we performed hopping and running simulations. The simulation results showed that the SLIP 2 model successfully achieves hopping and running motions. The hopping robot was also able to accomplish hopping motion. The simulation results also showed that the difference between the pelvic rotational phase and the phase of oscillation of the mass vertical displacement affects the jumping force. In particular, the results revealed that the human-like pelvic rotation contributes to the absorption of landing impact and to the increase in takeoff forces, which validates our observations in human motion analysis.

In this study we describe a terrain-adaptive biped walking control using a new biped foot mechanism with the capability of detecting ground surface. The foot system consists of three spikes each of which has an optical sensor to detect ground height. A robot modifies a foot-landing motion along the vertical axis and about pitch and roll axes according to sensor values, and this enables the robot to walk on unknown uneven terrain. Verification of the proposed control was conducted through experiments with a human-sized humanoid robot WABIAN-2R.

This paper proposes a stiffness analysis of biped walking vehicle that is based on a parallel kinematics architecture. Namely, WL-16RV (Waseda Leg No.16 Refined V) is a biped walking vehicle that can carry on board a human while overcoming typical human environment barriers. Experimental tests have been carried out on a built prototype of WL-16RV by using a specific set up for validation purposes.

Nowadays, the technologies for detecting, processing and interpreting bioelectrical signals have improved tremendously. In particular, surface electromyography (sEMG) has gained momentum in a wide range of applications in various fields. However, sEMG sensing has several shortcomings, the most important being: measurements are heavily sensible to individual differences, sensors are difficult to position and very expensive. In this paper, the authors will present an innovative muscle contraction sensing device (MC sensor), aiming to replace sEMG sensing in the field of muscle movement analysis. Compared with sEMG, this sensor is easier to position, setup and use, less dependent from individual differences, and less expensive. Preliminary experiments, described in this paper, confirm that MC sensing is suitable for muscle contraction analysis, and compare the results of sEMG and MC sensor for the measurement of forearm muscle contraction.

Different types of sensors are being used to study deglutition and mastication. These often suffer from problems related to portability, cost, reliability, comfort etc. that make it difficult to use for long term studies. An inertial measurement based sensor seems a good fit in this application; however its use has not been explored much for the specific application of deglutition research. In this paper, we present a system comprised of an IMU and EMG sensor that are integrated together as a single system. With a preliminary experiment, we determine that the system can be used for measuring the head-neck posture during swallowing in addition to other parameters during the swallowing phase. The EMG sensor may not always be a reliable source of physiological data especially for small clustered muscles like the ones responsible for swallowing. In this case, we explore the possibility of using gyroscopic data for the recognition of deglutition events.

In the past we achieved to use a rat-like robot and a single rat to develop Animal Models of Mental Disorder (AMMDs) through stress exposure. However, to simulate the real social environment, we use a rat-like robot composed of multiple links to chase a specific rat (target) in a group of rats (outside observers). In this paper, we aim to develop a real-time control system for a multi-link robot surrounded by multiple rats. A virtual impedance model was adopted to generate posture and trajectory for a multi-link robot named WR-5. With the analysis of virtual forces/moments acting on WR-5 based on the model, corresponding dynamic equations can be obtained to control the motion of WR-5. Simulation results show that the head of WR-5 can accurately direct a target object in the following test. After conducting experiments with three rat subjects (a target rat, two outside observers), the output results suggest that the head and body gesture of WR-5 achieves to follow the target in real-time. Meanwhile, the control system allows real-time avoidance of the moving outside observers during interaction.

Humanoid robots have this formidable advantage to possess a body quite similar in shape to humans. This body grants them, obviously, locomotion but also a medium to express emotions without even needing a face. In this paper we propose to study the effects of emotional gaits from our biped humanoid robot on the subjects' perception of the robot (recognition rate of the emotions, reaction time, anthropomorphism, safety, likeness, etc.). We made the robot walk towards the subjects with different emotional gait patterns. We assessed positive (Happy) and negative (Sad) emotional gait patterns on 26 subjects divided in two groups (whether they were familiar with robots or not). We found that even though the recognition of the different types of patterns does not differ between groups, the reaction time does. We found that emotional gait patterns affect the perception of the robot. The implications of the current results for Human Robot Interaction (HRI) are discussed.

We present a grid-based 3D reconstruction method which integrates all costs given by stereo vision into what we call a Cost-Curve Occupancy Grid (CCOG). Occupancy probabilities of grid cells are estimated in a Bayesian formulation, from the likelihood of stereo cost measurements taken at all distance hypotheses. This is accomplished with only a small set of probabilistic assumptions which we discuss in the paper. We quantitatively characterize the method's performance under different conditions of both image noise and number of used stereo pairs, compared also to traditional algorithms. We complement the study by giving insights on design choices of CCOGs such as likelihood model, window size of the cost function and use of a hole filling method. Experiments were made on a real-world outdoors dataset with ground-truth data.

This paper describes the development of a robotic head that has cartoon facial expression ability with comic marks. For communicating with humans, robots should have expressive facial expression ability for indicating their inner state. Our previous research suggests that robots can express its emotion clearly if it performs facial expressions that are adapted to the cultural background of the communication partner. As a first step, we focus on making expressions for Japanese people. Comic mark is a unique and famous way of emotion expression in Japanese culture. First, we defined facial expressions by combining cartoon-like shape of the facial parts with high emotion recognition rates. Then we asked cartoonists to draw comic marks which they think are effective for emotion expression and find the effective comic marks as "Cross popping veins" for "Anger", "Tear mark" for "Sadness" and "Vertical lines" for "Fear". Finally we obtained a model expression which has sufficiently high emotion recognition rate from the combination of the facial expression and the comic marks. In order to achieve these expressions, we developed flexible full color LED display matrix module and mechanism that push and pull the sheet for expressing black lines. Results of experimental evaluation shows that the new robotic head has over 90% average emotion recognition rates for each of the six basic emotions. The results with non-Japanese subjects suggests that impression of emotion expression on robotic head changes depending on the cultural background. These findings encourage us in pursuing this concept of designing robots that display emotions that are adapted to cultural background of communication partner.

This paper present a method for measuring the posture of a human body during different phases of sit to stand motion using inertial sensors. The proposed method fuses data from inertial sensors placed in trunk and thigh using Adaptive Neuro-Fuzzy Inference System (ANFIS) followed by a Kalman Filter (KF). The ANFIS attempts to estimate the position of shoulder of the human, at each sampling instant when measurement update step is carried out. The Kalman filter supervises the performance of the ANFIS with the aim of reducing the mismatch between the estimated and actual. The performance of the method is verified by measurements from VICON (motion analysis system). The obtained results show the effectiveness of the proposed algorithm in prediction the human shoulder position with root mean square error 0.018 m and 0.016 m in the x and y direction, respectively.

We propose a new biped locomotion planning method that optimizes locomotion speed subject to friction constraints. For this purpose we use approximate models of required coefficient of friction (RCOF) as a function of gait. The methodology is inspired by findings in human gait analysis, where subjects have been shown to adapt spatial and temporal variables of gait in order to reduce RCOF in slippery environments. Here we solve the friction problem similarly, by planning on gait parameter space: namely foot step placement, step swing time, double support time and height of the center of mass (COM). We first used simulations of a 48 degrees-of-freedom robot to estimate a model of how RCOF varies with these gait parameters. Then we developed a locomotion planning algorithm that minimizes the time the robot takes to reach a goal while keeping acceptable RCOF levels.
Our physics simulation results show that RCOF-aware planning can drastically reduce slippage amount while still maximizing efficiency in terms of locomotion speed. Also, according to our experiments human-like stretched-knees walking can reduce slippage amount more than bent-knees (i.e. crouch) walking for the same speed.

In this paper, we describe the development of a leg with a rotational joint that mimics the elastic characteristics of the leg of a running human. The purpose of this development was to realize the dynamics of human running, the analysis of which has revealed that the motion of the leg can be modeled by a compression spring and that of the leg joint by a torsion spring. We, therefore, assumed that these elastic characteristics could be used to develop robots capable of human-like running, which requires higher output power than that of existing humanoid robots. Hence, we developed a model of a leg with a rotational joint and fabricated the leg by incorporating a mechanism comprising of two leaf springs for adjusting the joint stiffness. By this means, we were able to achieve human-like joint stiffness, which could be adjusted by varying the effective length of one of the leaf springs. We evaluated the performance of the adjustable stiffness of the joints, and were also able to achieve hopping by resonance of the rotational leg joint.

Although consistent stability is desirable, a biped humanoid robot encounters a high risk of falling. Such falls may cause serious damage to both the robot and the environment. This study focuses on this issue and investigates four strategies based on human protective falling motion. These strategies are: "knee flexion", "torso flexion forward", "torso translation backward" and "knee stretched". First, the effectiveness of the strategies for the safe landing is analyzed from an energy variation perspective of the robot system. The four strategies are used to do negative work that reduced the energy of the robot system, thereby reducing the impact velocity of the robot. Then, a simulation study on a human-sized humanoid robot is conducted to assess the influence of the strategies on safe landing. Finally, based on the simulation results for each strategy, a safe falling motion control method is proposed and validated through simulation.

Human running motion can be modeled by a spring loaded inverted pendulum (SLIP). However, this model, despite being widely used in robotics, does not include human-like pelvic motion. In this study, we show that the pelvis actually contributes to the increase in jumping force and absorption of landing impact, both of which findings can be used to improve running robots. On the basis of the analysis of human running motion, we propose a new model named SLIP 2 (spring loaded inverted pendulum using pelvis). This model is composed of a body mass, a pelvis, and leg springs; the model can control its springs during running by use of pelvic movement in the frontal plane. To achieve hopping and running motions, we developed pelvis oscillation control, running velocity control, and stabilization control using an upper body, as control methods. We also developed a new hopping robot using the SLIP 2 model. To evaluate the proposed model and control methods, we performed hopping and running simulations. The simulation results showed that the SLIP 2 model successfully achieves hopping and running motions. The hopping robot was also able to accomplish hopping motion. The simulation results also showed that the difference between the pelvic rotational phase and the phase of oscillation of the mass vertical displacement affects the jumping force. In particular, the results revealed that the human-like pelvic rotation contributes to the absorption of landing impact and to the increase in takeoff forces, which validates our observations in human motion analysis.

We develsoped a novel small rat-like robot called Waseda Rat No. 4 (WR-4) to interact with real rats. WR-4 can perform both rearing (rising up on its hind limbs) and rotating (body bending during movement) actions faster than live mature rats. After robot-rat interaction involving rearing and body grooming (body cuddling and head curling) actions of WR-4, real rats showed more activity and greater interest in the robot. Similar results evident from rat-rat interaction suggest that a rat-like robot is able to interact with rats in the same way as real rats. Furthermore, lower variances between the rat subjects in robot-rat interaction reveals that a rat-like robot can more effectively impact rat's behavior in a controllable, predictable way. Copyright © Cambridge University Press 2013.

Emotion display through facial expressions is an important channel of communication. However, between humans there are differences in the way a meaning to facial cues is assigned, depending on the background culture. This leads to a gap in recognition rates of expressions: this problem is present when displaying a robotic face too, as a robot's facial expression recognition is often hampered by a cultural divide, and poor scores of recognition rate may lead to poor acceptance and interaction. It would be desirable if robots could switch their output facial configuration flexibly, adapting to different cultural backgrounds. To achieve this, we made a generation system that produces facial expressions and applied it to the 24 degrees of freedom head of the humanoid social robot KOBIAN-R, and thanks to the work of illustrators and cartoonists, the system can generate two versions of the same expression, in order to be easily recognisable by both Japanese and Western subjects. As a tool for making recognition easier, the display of Japanese comic symbols on the robotic face has also been introduced and evaluated. In this work, we conducted a cross-cultural study aimed at assessing this gap in recognition and finding solutions for it. The investigation was extended to Egyptian subjects too, as a sample of another different culture. Results confirmed the differences in recognition rates, the effectiveness of customising expressions, and the usefulness of symbols display, thereby suggesting that this approach might be valuable for robots that in the future will interact in a multi-cultural environment. © 2013 Springer Science+Business Media Dordrecht.

The purpose of this study was to determine safe techniques of performing blood collection using an evacuated tube system, particularly with regard to manipulation of the equipment and at the puncture site. Careful observation of the procedure was used to collect data for evaluating the various venepuncture techniques. Nurses were digitally videotaped performing simulated venepuncture. A self-administered questionnaire and unstructured observation of a videotaped recording were evaluated, and valid responses were analyzed from participants who performed venepuncture using various techniques. The participants who changed hands during the procedure were older than those who did not change hands. Needle movements during puncture and insertion, including rotation and insertion in a wave-like trajectory, were observed. Appropriate training, including recommendations for maintaining the stability of the needle tip, is important to ensure safety when performing venepuncture. Movement of the needle should not place too much pressure on the puncture site. © 2013 Wiley Publishing Asia Pty Ltd.

This study describes a biped walking stabilization based on gait analysis for a humanoid robot. So far, we have developed a humanoid robot as a human motion simulator which can quantitatively evaluate welfare and rehabilitation instruments instead of human subjects. However, the walking motion of the robot looked like humans in our past researches, but a walking stabilization control was not based on gait analysis. To use a humanoid robot as a human motion simulator, not only mechanisms but also a stabilizer should be designed based on human beings. Of course, there are many studies on gait analysis in the field of neuroscience, but most of them are not modeled enough to be implemented on humanoid robots. Therefore, first, we conducted gait analysis in this study, and we obtained following two findings: (i) a foot-landing point exists on the line joining the stance leg and the projected point of center of mass on the ground, and (ii) the distance between steps is modified to keep mechanical energy at the landing within a certain value. A walking stabilization control is designed based on the gait analysis. Verification of the proposed control is conducted through experiments with a human-sized humanoid robot WABIAN-2R. © 2013 Taylor &amp
Francis and The Robotics Society of Japan.

Communication between humans and robots is a very important aspect in the field of Humanoid Robotics. For a natural interaction, robots capable of nonverbal communication must be developed. However, despite the most recent efforts, robots still can show only limited expression capabilities. The purpose of this work is to create a facial expression generator that can be applied to the 24 DoF head of the humanoid robot KOBIAN-R. In this manuscript, we present a system that based on relevant studies of human communication and facial anatomy can produce thousands of combinations of facial and neck movements. The wide range of expressions covers not only primary emotions, but also complex or blended ones, as well as communication acts that are not strictly categorized as emotions. Results showed that the recognition rate of expressions produced by this system is comparable to the rate of recognition of the most common facial expressions. Context-based recognition, which is especially important in case of more complex communication acts, was also evaluated. Results proved that produced robotic expressions can alter the meaning of a sentence in the same way as human expressions do. We conclude that our system can successfully improve the communication abilities of KOBIAN-R, making it capable of complex interaction in the future. © 2013 World Scientific Publishing Company.

Walking is one of the most common activities that we perform every day. If the main goal of walking is to go from a point A to a point B, walking can also convey emotional clues in social context. Those clues can be used to improve interactions or any messages we want to express. We observed a professional actress perform emotive walking and analyzed the recorded data. For each emotion, we found characteristic features which can be used to model gait patterns for humanoid robots. The findings were assessed by subjects who were asked to recognize the emotions displayed in the acts of walking. © 2013 IEEE.

The research on the development of the anthropomorphic flutist robot at Waseda University has been focused in emulating the anatomy and physiology of the organs involved during the flute playing from an engineering point of view, facilitating the symbiosis between the human and the robot (i.e. active interaction between musician and musical robot) and proposing novel applications for humanoid robots (i.e. music education). As a result of this research, the Waseda Flutist Robot No. 4 Refined IV has been developed and a musical-based interaction system implemented so the robot is capable of interacting with musicians by processing both aural and visual cues. However; there is a trade-off relationship between the duration of the flute sound produced by the robot and the sound pressure (volume). In fact, the robot is only capable of playing sounds low-pitched sounds for long periods. In addition, a husky sound is detected while playing high-pitch sounds. From our discussions with professional players, this effect is caused due to the inner shape of the oral cavity. From this, the conversion efficiency ratio between from the exhaled air from the artificial lungs to the produced sound is too low. For this purpose, we have obtained MR images of the head from professional players in order to re-design the oral cavity of the flutist robot. A total of 5 prototypes were tested and the best one has been selected and integrated into the Waseda Flutist Robot No. 4 Refined VI (WF-4RVI). A set of experiments were proposed in order to verify the improvements of the conversion efficiency ratio as well as the sound evaluation function score. From the experimental results, we could verify the improvements compared with the previous version of the flutist robot.

Physicians use ultrasound scans to obtain real-time images of internal organs, because such scans are safe and inexpensive. However, people in remote areas face difficulties to be scanned due to aging society and physician's shortage. Hence, it is important to develop an autonomous robotic system to perform remote ultrasound scans. Previously, we developed a robotic system for automatic ultrasound scan focusing on human's liver. In order to make it a completely autonomous system, we present in this paper a way to autonomously localize the epigastric region as the starting position for the automatic ultrasound scan. An image processing algorithm marks the umbilicus and mammary papillae on a digital photograph of the patient's abdomen. Then, we made estimation for the location of the epigastric region using the distances between these landmarks. A supporting algorithm distinguishes rib position from epigastrium using the relationship between force and displacement. We implemented these algorithms with the automatic scanning system into an apparatus: a Mitsubishi Electric's MELFA RV-1 six axis manipulator. Tests on 14 healthy male subjects showed the apparatus located the epigastric region with a success rate of 94%. The results suggest that image recognition was effective in localizing a human body part.

In this paper a novel approach to kinematics learning and task space control, under switching contexts, is presented. Such non-stationary contexts may appear in many robotic tasks: in particular, the changing of the context due to the use of tools with different lengths and shapes is herein studied. We model the robot forward kinematics as a multi-valued function, in which different outputs for the same input query are related to actual different hidden contexts. To do that, we employ IMLE, a recent online learning algorithm that fits an infinite mixture of linear experts to the online stream of training data. This algorithm can directly provide multi-valued regression in a online fashion, while having, for classic single-valued regression, a performance comparable to state-of-the-art online learning algorithms. The context varying forward kinematics is learned online through exploration, not relying on any kind of prior knowledge. Using the proposed approach, the robot can dynamically learn how to use different tools, without forgetting the kinematic mappings concerning previously manipulated tools. No information is given about such tool changes to the learning algorithm, nor any assumption is made about the tool kinematics. To our knowledge this is the most general and efficient approach to learning and control under discrete varying contexts. Some experimental results obtained on a high-dimensional simulated humanoid robot provide a strong support to our approach.

This paper describes the mechanism and vertical jumping pattern of a one-legged jumping robot that can mimic the muscular and skeletal system of a human leg. The jumping robot has a waist, a thigh, a shin, a foot, and a toe. Its weight is 12.34 kg, and its height is 1010 mm. It has a total of 13 actuators: 10 mono-articular types and 3 bi-articular types. Two kinds of pneumatic artificial muscles such as mono-articular and bi-articular muscles are installed in the rear and the front of the thigh and shin to antagonize each other. For a vertical jump, a joint angle pattern is developed based on the linear and angular momentum. The effectiveness of the mechanism and the jumping pattern of the robot are verified through simulations and experiments.

Performing laparoscopic surgery requires several skills, which have never been required for conventional open surgery. Surgeons experience difficulties in learning and mastering these techniques. Various training methods and metrics have been developed to assess and improve surgeon's operative abilities. While these training metrics are currently widely being used, skill evaluation methods are still far from being objective in the regular laparoscopic skill education. This study proposes a methodology of defining a processing model that objectively evaluates surgical movement performance in the routine laparoscopic training course. Our approach is based on the analysis of kinematic data describing the movements of surgeon's upper limbs. An ultraminiaturized wearable motion capture system (Waseda Bioinstrumentation system WB-3), therefore, has been developed to measure and analyze these movements. The data processing model was trained by using the subjects' motion features acquired from the WB-3 system and further validated to classify the expertise levels of the subjects with different laparoscopic experience. Experimental results show that the proposed methodology can be efficiently used both for quantitative assessment of surgical movement performance, and for the discrimination between expert surgeons and novices. © 1964-2012 IEEE.

Walking is one of the most common activities that we perform every day. If the main goal of walking is to go from a point A to a point B, walking can also convey emotional clues in social context. Those clues can be used to improve interactions or any messages we want to express. We observed a professional actress perform emotive walking and analyzed the recorded data. For each emotion, we found characteristic features which can be used to model gait patterns for humanoid robots. The findings were assessed by subjects who were asked to recognize the emotions displayed in the acts of walking.

Neurologic examination procedures require not only abundant knowledge but also prominent skills. During medical education and training, several methods will be put to use such as watching video, reading books, making use of the simulated patient (SP), and so on. These can help medical staffs, especially novices, to master the skills and accumulate experiences. To make up for the drawbacks of the above methods, such as lack of active interactions, limitation of multi-symptom reproductions, etc, the medical training simulators have been developed to improve training effectiveness. However, most of these simulators only mimic the symptoms. They have no the abilities to show the pathology of diseases. This limits the training effectiveness. In this paper, we propose an elbow robot named WKE-1(Waseda Kyotokagaku Elbow Robot No. 1) for neurologic examination training as one part of the whole body patient robot named WKP (Waseda Kyotokagaku Patient). In this robot, we simulate various symptoms occurring during the examination of elbow force, biceps tendon reflex, involuntary action, and also make a physiological neurological model to simulate the pathology of the nervous system. Taking advantage of this robot, the trainee can get a systematic training on both the skills and knowledge. Finally, we take a set of experiments to verify our proposed mechanism and system. The experimental results lead to the consideration that the approach is worth following in further research.

The authors propose a comparison between two force-position controllers with gravity compensation simulated on the DEXTER bioinspired robotic arm. The two controllers are both constituted by an internal proportional-derivative (PD) closed-loop for the position control. The force control of the two systems is composed of an external proportional (P) closed-loop for one system (P system) and an external proportional-integrative (PI) closed-loop for the other system (PI system). The simulation tests performed with the two systems on a planar representation of the DEXTER, an eight-DOF bioinspired arm, showed that by varying the stiffness of the environment, with a correct setting of parameters, both systems ensure the achievement of the desired force regime and with great precision the desired position. The two controllers do not have large differences in performance when interacting with a lower stiffness environment. In case of an environment with greater rigidity, the PI system is more stable. The subsequent implementation of these control systems on the DEXTER robotic bioinspired arm gives guidance on the design and control optimisation of the arms of the humanoid robot named SABIAN. © 2013 Giovanni Gerardo Muscolo et al.

EMG sensors for biomechanics research and portable applications need to be small, wireless and power efficient. This imposes several constraints on the design methodology of such sensors. There are many commercially available devices which are expensive and have proprietary communication protocols. It is difficult to synchronize them with other devices. Furthermore, using gel-based electrodes for signal acquisition increases setup time and running costs.
Hence we present the design of a miniaturized, wireless, low-cost and non-invasive dry-electrode EMG sensor that was prototyped in our lab and dubbed the 'WB-EMG' Sensor. We demonstrate its working being fitted with a gold plated copper core electrode. By mounting the sensor on the extensor carpi ulnaris and recording data during some simple exercises, we were able to show that its envelope in the frequency domain was similar to the expected EMG Pattern.

Physical therapy helps patients to restore the use of the musculoskeletal and the nervous systems through the use of specifics techniques and exercises. The introduction of measurement systems for patient assessment may allow detection of initial stage of diseases, an objective severity assessment, and efficient delivery of drugs and therapies. In rehabilitation centers, sometimes there are specific devices and methodologies available for the locomotion assessment. However, the measurements are usually carried out in a short time slot and this could lead to an overestimation of the walking abilities. © 2013 IEEE.

The increasing age of the world population is posing new challenges to our society, such as how to keep this aging population healthy and active despite of the age. In recent years, there has been a lot of interest for gait analysis for rehabilitation purposes as well as for performance assessment of this aging population. While current systems work well, they still have several limitations. Cost, need for specialized personnel, need to be used in a research center, and sporadic measurement prevent these systems from being widely used.
The authors propose the use of extremely miniaturized, portable measurement systems, which can be worn by the users during their everyday life, and can monitor their gait over a long timespan. This paper presents the preliminary experiments with such a system.

Endotracheal Intubation (ETI) is a common airway procedure used to connect the larynx and the lungs through a windpipe in patients under emergency situations. The process is carried out by a laryngoscope inserted into the mouth, used to help doctors in visualizing the glottis and inserting the tube. Currently, very few studies on objective evaluation of the biomechanics of the doctors during the procedure have been done. Additionally, these studies have been concentrated only on the overall performance analysis, without any segmentation, with a consequent loss of important information. In this paper, the authors present a preliminary study on a methodology to objectively evaluate and segment the biomechanical performance of doctors during the ETI, using surface electromyography and inertial measurement units. In particular, the validation has been performed by comparing three kinds of laryngoscopes involving an expert doctor. Finally, results are presented and commented.

Performing laparoscopic surgery requires several skills, which have never been required for conventional open surgery. Surgeons experience difficulties in learning and mastering these techniques. Various training methods and metrics have been developed to assess and improve surgeon's operative abilities. While these training metrics are currently widely being used, skill evaluation methods are still far from being objective in the regular laparoscopic skill education. This study proposes a methodology of defining a processing model that objectively evaluates surgical movement performance in the routine laparoscopic training course. Our approach is based on the analysis of kinematic data describing the movements of surgeon's upper limbs. An ultraminiaturized wearable motion capture system (Waseda Bioinstrumentation system WB-3), therefore, has been developed to measure and analyze these movements. The data processing model was trained by using the subjects' motion features acquired from the WB-3 system and further validated to classify the expertise levels of the subjects with different laparoscopic experience. Experimental results show that the proposed methodology can be efficiently used both for quantitative assessment of surgical movement performance, and for the discrimination between expert surgeons and novices. © 1964-2012 IEEE.

This paper describes the implementation in a walking humanoid robot of a mental model, allowing the dynamical change of the emotional state of the robot based on external stimuli; the emotional state affects the robot decisions and behavior, and it is expressed with both facial and whole-body patterns. The mental model is applied to KOBIAN-R, a 65-DoFs whole body humanoid robot designed for human-robot interaction and emotion expression. To evaluate the importance of the proposed system in the framework of human-robot interaction and communication, we conducted a survey by showing videos of the robot behaviors to a group of 30 subjects. The results show that the integration of dynamical emotion expression and locomotion makes the humanoid robot more appealing to humans, as it is perceived as more "favorable" and "useful", and less "robot-like."

Walking is one of the most common activities that we perform every day. Even if the main goal of walking is to move from one place to another place, walking can also convey emotional clues in social context. Those clues can be used to improve interactions or any messages we want to express. However, there are not many studies on the effects of the intensity of the emotions on the walking. In this paper, the authors propose to assess the differences between the expression of emotion regarding the expressed intensity (low, middle, high and exaggerated). We observed two professional actors perform emotive walking, with different intensities and we analyzed the recorded data. For each emotion, we analyzed characteristic features which can be used in the future to model gait patterns and to recognize emotions from the gait parameters. Additionally, we found characteristics which can be used to create new emotion expression for our biped robot Kobian, improving the human-robot interaction.

The understanding of emotions in humans is really important in the Human-Robot Interaction field. The affective state of a person can be expressed in several ways, one of them being through the way we walk and our gait can convey emotional clues in social context. Those clues can be used to improve the personal interactions with our peers or add meaning to any message we want to express. However, only a few studies in humanoid robotics were done on the effects of the emotions on the walking. In this paper, we propose to assess the emotional walking patterns created from motion capture data with a survey. Those patterns represent different emotions (sadness, happiness) with different intensities (middle, high and exaggerated). Those emotional walking patterns achieved a high recognition rate of the emotions and the subjects (N=13) could recognize whole body emotions without facial expression on our humanoid robot. Additionally, we found out that at first people might perform poorly at recognizing emotions and their intensities but can get better, even without correction or feedback on their performances. © 2013 IEEE.

A complex relationship exists between national cultural background and interaction with robots, and many earlier studies have investigated how people from different cultures perceive the inclusion of robots into society. Conversely, very few studies have investigated how robots, speaking and using gestures that belong to a certain national culture, are perceived by humans of different cultural background. The purpose of this work is to prove that humans may better accept a robot that can adapt to their specific national culture. This experiment of Human-Robot Interaction was performed in Egypt. Participants (native Egyptians versus Japanese living in Egypt) were shown two robots greeting them and speaking respectively in Arabic and Japanese, through a simulated video conference. Spontaneous reactions of the human subjects were measured in different ways, and participants completed a questionnaire assessing their preferences and their emotional state. Results suggested that Egyptians prefer the Arabic version of the robot, while they report discomfort when interacting with the Japanese version. These findings confirm the importance of a culture-specific customisation of robots in the context of Human-Robot Interaction. © 2013 IEEE.

We propose a two-stage gait pattern generation scheme for the full-scale humanoid robots, that considers the dynamics of the system throughout the process. The fist, stage is responsible for generating the preliminary motion reference, such as step position, timing and trajectory of Center of Mass (CoM), while the second stage serves as dynamics filter which employs a multi-body model and based on Zero Moment Point (ZMP) reference trajectory generates CoM reference trajectory which defines a locomotion stable when executed on the full-scale multi-degree-of-freedom humanoid robot. The approach thanks to introducing a dynamic model at, the stage of feet placement planning provides the ZMP reference, which is ensured to be feasible for the robot. Thanks to the fact it enables instantaneous regeneration of motion. The paper contains description of two approaches used in the first and second stage, as well as experimental results proving the effectiveness of the method. The fast calculation time and the use of the system's dynamic state as initial conditions for pattern generation makes it a good candidate for the real-time gait pattern generator.

We propose a two-stage gait pattern generation scheme for the full-scale humanoid robots, that considers the dynamics of the system throughout the process. The fist stage is responsible for generating semi-dynamically consistent step position and step time information, while the second stage incorporated with multi-body dynamics system is responsible for generation of gait pattern that is feasible and stable on the full-scale multi-degree-of-freedom humanoid robot. The approach allows for very rapid gait pattern regeneration during the swing phase of motion and includes information about present dynamic state when regenerating the new pattern. The paper contains description of a developed method, as well as experimental results proving its effectiveness.

Neurological examinations are among the most important clinical skills to identify disorders in the neurological system at early stages. Training on neurological examination for inexperienced doctors plays an important role in improving accuracy of diagnosis. Such training programs have been conducted until now using physical simulators or simulated patients (SPs). However, conventional simulators can simulate only facial features of patients and not their responses or motions. SP cannot simulate them either. We have therefore been developing a whole-body patient robot named WKP(Waseda Kyotokagaku Patient robot) for training on neurological examination. The main advantage of WKP over conventional simulators and SPs is its ability to simulate motions and responses of patients having disorders in their neurological systems. We then developed a head humanoid with facial expression for training on neurological disorders as a part of WKP. This humanoid is equipped with 21 degrees of freedom
it has 2 liquid crystal panels with lenses, and simulates facial movements with imitating the wrinkles and eyeball movements of patients with disorders in their cranial nerves. We then performed a set of experiments to validate the head humanoid. The main focus of this paper is on mechanical design and performance verification of the head humanoid. © 2013 IEEE.

Endotracheal Intubation (ETI) is a common airway procedure used to connect the larynx and the lungs through the windpipe of patients under emergency situations. The process is carried out by a laryngoscope inserted into the mouth, and helps doctors in viewing the glottis and inserting the tube. In 2012, we developed a humanoid robot for ETI training, called WKA-5R, which was able to simulate various patients and scenarios and to evaluate the doctor's medical skills according to applied force, position of laryngoscopes and tubes, and procedure time. In 2013, we have focused our study on the development of a system for the biomechanical evaluation during simulated ETI. We conducted an experiment with 5 expert and 6 novice anesthesiologists and measured 3 biomechanical parameters: angular velocity of wrist joint and elbow joint, surface electromyography (sEMG) of the upper limb, and some angles on the upper part of the body, in order to evaluate joint stiffness in the arm and posture during ETI. In this paper, the authors show the experimental results on comparison between experts and novices, followed by discussion. © 2013 IEEE.

Physicians use ultrasound scans to do diagnosis by making real-time images of internal organs, because such scans are safe, inexpensive, and non-invasive. However, aging society and limited numbers of physician make it difficult for patients in remote areas to be diagnosed. Besides, physician's technical skills affect the interpretation of the scans and thus the results of the examination. Thus, development of a robotic system for remote diagnosis is required to solve the problems. For this purpose, we proposed the development of a robotic system for automatic ultrasound imaging focusing on human liver. In this paper, we present several elements developed for the robotic system. First element is an algorithm for estimating the position of liver to guide the probe to scan initial position which is the epigastric region. Second element is ultrasound probe scanning protocol design to obtain whole image of the liver. Third element is force control algorithm to maintain the contact between the probe and human body even though the patient is breathing. Fourth element is an algorithm for detecting and correcting the probe's position when improper ultrasound images occurred. These algorithms with an implementation program control the apparatus: a Mitsubishi Electric's MELFA RV-1 six axis manipulator and tested on human subjects. The results confirmed the effectiveness of the approach. © 2013 IEEE.

this paper describes a novel mobility assistive device under development in the Egypt-Japan University of Science and Technology (E-JUST). The proposed system can help patients who do not have enough physical strength on the lower limbs during sit to stand due to aging, diseases such as polymyositis and myopathy, and joint replacement surgery complications. It can follow the natural pattern of human motion during sit to stand providing assistance force under the shoulder. The overall device is compact and employees a parallel mechanism which provide more stiffness. Several experiments were carried out in a VICON room to calculate the human motion posture while sit to stand motion in addition estimate the trajectory of the end effector during assisting. Computer simulation was built to verify the performance of the proposed system with the reference trajectory.

Endotracheal Intubation (ETI) is a common airway procedure used to connect the larynx and the lungs through the windpipe of patients under emergency situations. The process is carried out by a laryngoscope inserted into the mouth, and helps doctors in viewing the glottis and inserting the tube. In 2012, we developed a humanoid robot for ETI training, called WKA-5R, which was able to simulate various patients and scenarios and to evaluate the doctor's medical skills according to applied force, position of laryngoscopes and tubes, and procedure time. In 2013, we have focused our study on the development of a system for the biomechanical evaluation during simulated ETI. We conducted an experiment with 5 expert and 6 novice anesthesiologists and measured 3 biomechanical parameters: angular velocity of wrist joint and elbow joint, surface electromyography (sEMG) of the upper limb, and some angles on the upper part of the body, in order to evaluate joint stiffness in the arm and posture during ETI. In this paper, the authors show the experimental results on comparison between experts and novices, followed by discussion. © 2013 IEEE.

A common problem among elderly people is the loss of motor ability. Rehabilitation exercises can help these people recover strength and maintain a good level of mobility. However, high costs and the need for special equipment make professional rehabilitation impractical for regular use in daily life, precluding elderly the possibility to perform focalized training at home. The idea of telerehabilitation is becoming more and more concrete with the rapid development of internet technology. Telerehabilitation would allow the user to perform exercises at home with online professional direction from the doctor. However, at the present state, the doctor cannot obtain real-time and quantitative data from the user, and this limits the training effectiveness. To overcome this problem, an extremely miniaturized, portable motion capture system, named WB-4R, has been developed. Calibration and real-time link orientation reconstruction are very important to improve the accuracy in real-time measurement. In this paper, using the positive results of preliminary experiments on lower limbs, the authors will show the feasibility of the method and confirm the effectiveness of the developed system.

In this paper, we describe a human gesture recognition system developed to make a humanoid robot understand non-verbal human social behaviors, and we present the results of preliminary experiments to demonstrate the feasibility of the proposed method. In particular, we have focused on the detection and recognition of laughter, a very peculiar human social signal. In fact, although it is a direct form of social interaction, laughter is classified as semi voluntary action, can be elicited by several different stimuli, and it is strongly associated with positive emotion and physical well-being. The possibility of recognize, and further elicit laughter, will help the humanoid robot to interact in a more natural way with humans, to build positive relationships and thus be more socially integrated in the human society.

We present a novel control architecture for the integration of visually guided walking and whole-body reaching in a humanoid robot.We propose to use robot gaze as a common reference frame for both locomotion and reaching, as suggested by behavioral neuroscience studies in humans. A gaze controller allows the robot to track and fixate a target object, and motor information related to gaze control is then used to i) estimate the reachability of the target, ii) steer locomotion, iii) control whole-body reaching. The reachability is a measure of how well the object can be reached for, depending on the position and posture of the robot with respect to the target, and it is obtained from the gaze motor information using a mapping that has been learned autonomously by the robot through motor experience: we call this mapping Reachable Space Map. In our approach, both locomotion and whole-body movements are seen as ways to maximize the reachability of a visually detected object, thus i) expanding the robot workspace to the entire visible space and ii) exploiting the robot redundancy to optimize reaching. We implement our method on a full 48-DOF humanoid robot and provide experimental results in the real world.

Designing humanoid robots able to interact socially with humans is a challenging task. If we want the robots to be actively integrated in our society, several issues have to be taken in account: the look of the robot, the naturalness of its movements, the stability of its walk, the reactivity it might have with its human partners. We propose to improve the reactivity of the robot by using a emotional mental model in order to generate emotional gait patterns. Those patterns will help the understanding of any emotional message conveyed between a human and a robot. We propose a novel emotional gait generation method based on the Emotion mental model. We did preliminary experiments with the Happiness and Sadness emotions and with different intensities.

Extensive literature has been written on occupancy grid mapping for different sensors. When stereo vision is applied to the occupancy grid framework it is common, however, to use sensor models that were originally conceived for other sensors such as sonar. Although sonar provides a distance to the nearest obstacle for several directions, stereo has confidence measures available for each distance along each direction. The common approach is to take the highest-confidence distance as the correct one, but such an approach disregards mismatch errors inherent to stereo.
In this work, stereo confidence measures of the whole sensed space are explicitly integrated into 3D grids using a new occupancy grid formulation. Confidence measures themselves are used to model uncertainty and their parameters are computed automatically in a maximum likelihood approach. The proposed methodology was evaluated in both simulation and a real-world outdoor dataset which is publicly available. Mapping performance of our approach was compared with a traditional approach and shown to achieve less errors in the reconstruction.

Humanoid robots progress everyday closer and closer to a more stable walking suitable for a human environment as the researchers in the Humanoid robotics field focus their effort on the understanding of the human locomotion. Nonetheless for Social Robotics researchers, humanoid robots might have another use, such as being our companions from birth to nursing home. Designing social humanoid robots is one critical step if we want the robots to be active in our society. However, to our knowledge, only a few studies in the area of humanoid robotics have addressed emotion expression with robot gaits. In this paper we propose to assess different emotional gait patterns and the perception of the emotion intensity in those patterns. Actors' emotional movement were captured and then normalized for our robot platform. Several robot simulations were shown to human observers who completed a survey questionnaire in which they indicated their assessment of the portrayed emotion by the robot simulation. The surveyed emotions consist of Sadness, Happiness, Anger, Fear with different intensities (Intermediate, High and Exaggerated). We achieved a high recognition rate of emotions (72.32%). Even if the intensities were less well recognized (33.63%), our study indicates that the intensity might help the recognition of emotional walking.

We developed a three-dimensional mechanical vocal cord model for Waseda Talker No. 7 (WT-7), an anthropomorphic talking robot, for generating speech sounds with various voice qualities. The vocal cord model is a cover model that has two thin folds made of thermoplastic material. The model self-oscillates by airflow exhausted from the lung model and generates the glottal sound source, which is fed into the vocal tract for generating the speech sound. Using the vocal cord model, breathy and creaky voices, as well as the modal (normal) voice, were produced in a manner similar to the human laryngeal control. The breathy voice is characterized by a noisy component mixed with the periodic glottal sound source and the creaky voice is characterized by an extremely low-pitch vibration. The breathy voice was produced by adjusting the glottal opening and generating the turbulence noise by the airflow just above the glottis. The creaky voice was produced by adjusting the vocal cord tension, the sub-glottal pressure and the vibration mass so as to generate a double-pitch vibration with a long pitch interval. The vocal cord model used to produce these voice qualities was evaluated in terms of the vibration pattern as measured by a high-speed camera, the glottal airflow and the acoustic characteristics of the glottal sound source, as compared to the data for a human. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2012

In animal behavior research, rat models of mental disorders (RMMDs) are developed to screen psychotropic drugs and to clarify the mechanism of mental disorders. Meanwhile, interaction between real rats is used to evaluate the RMMD. However, since rat-rat interaction is hard to control and quantify, we have adopted a bio-inspired robot to interact with real rats owing to its programmability and reconfigurability in testing different models. We have developed several rat-like robots before, however, these robots still can not fully satisfy the requirement of animal experiment. As an improvement, the newest generation rat-like robot called WR-5 is developed. WR-5 can perform mounting and grooming actions naturally as live mature rat owing to adopted differential gear in its waist. Preliminary SIT between WR-5 and mature rats have been conducted strictly following psychological rules. Experimental results show that rats are more active and have fewer frequencies of grooming and rearing actions when WR-5 performs mounting action periodically. The rat-like robot is therefore able to make the anxiety level of rats high by means of performing mounting action.

In this paper, we proposed an automated video processing system to replace the traditional manual annotation, and to improve the adaptivity of the rat-like robot to autonomously interact with rats. The feature parameters of rats, such as body length, body area, circularity, body bend angle, locomotion speed, etc., are extracted based on image processing. These parameters are integrated as the input feature vector of Artificial Neural Network (ANN) and Support Vector Machine (SVM) classification methods respectively. Preliminary experiments reveal that the rearing, grooming and rotating actions could be recognized with extremely high rate (more than 90% by SVM and more than 80% by ANN). Furthermore, SVM needs less training computational cost than ANN. Therefore, SVM is superior to ANN for the behavior recognition of rats. By using the SVM-based recognition system, the behavior of the robot is generated adaptive to the rat behavior for different interactions.

The cranial nerves examination is one part of neurological examination. Neurologic medical staffs, especially the novices, need to be trained and grasp this skill. There are various methodologies to help the trainee to accumulate experiences. However, the best way is to practice on the real patient. The methods have their own drawbacks such as lack of active interactions, limitation of multi-symptoms' reproducing, etc. In order to improve the training effectiveness, a face robot (Fig. 1) is proposed in this paper for cranial nerves examination training as one part of the whole body patient robot named WKP (Waseda Kotokagaku Patient). In this robot, various symptoms of optical tracking, eyeball movements, facial paralysis are simulated and shown to the trainee. Finally, a set of experiments was performed to evaluate our proposed mechanism and control system. Three neurologists with over 30 years' experience were invited to show their opinions on the reproductions of the symptoms, and to discuss the results. All the results lead to the improvements for further research.

During several years of development, the hardware of the anthropomorphic flutist robot Waseda Flutist WF-4RIV has been continuously improved. The robot is currently able to play the flute at the level of an intermediate human player. Lately we have been focusing our research on the interactivity of the performance of the robot. Initially the robot has only been able to play a static performance that was not actively controllable by a partner musician of the robot. In a realistic performance set-up, in a band or an orchestra, musicians need to interact in order to create a performance that gives a natural and dynamic impression to the audience. In this publication we present the latest developments on the integration a Musical-based Interaction System (MbIS) with WF-4RIV. Such a human robot interaction system is to allow human musicians to do natural musical communication with the flutist robot through audio-visual cues. Here we would like to summarize our previous results, present the latest extensions to the system and especially concentrate on experimenting with applications of the system. We evaluate our interactive performance system using three different methods: A comparison of a passive (non-interactive) and an interactive performance, evaluation of the technical functionality of the interaction system as a whole and by examining the MbIS from a user perspective with a user survey including amateur and professional musicians. We present experiment results that show that our Musical-based Interaction System extends the anthropomorphic design of the flutist robot, to allow increasingly interactive, natural musical performances with human musicians.

Neurologic examination takes an important role in diagnosis of the nerve system diseases. Neurologic medical staffs, especially the novices, need to be trained on this skill. There are many methodologies which can help to accumulate experiences, such as watching video, reading books, making use of the simulated patient (SP), and so on. However, the best way is to practice on the real patient. All the above methods have their own drawbacks such as lack of active interactions, limitation of multi-symptoms' reproducing, etc. To improve the training effectiveness, an arm robot is proposed in this paper for neurologic examination training as one part of the whole body patient robot named Waseda Kyotokagaku Patient (WKP). In this robot, various symptoms of the elbow force, biceps tendon reflex, involuntary action, and so on, are simulated and shown to the trainee. Finally, a set of experiments was carried out to verify our proposed mechanism and control system. Three neurologists with over 30 years' experience were invited to show their opinions on the reproductions of patients' symptoms, and to discuss the results. The effectiveness of this system was confirmed. The experimental results lead to the consideration that the approach is worth following in further research.

The purpose of this study is to develop novel training system for medical skills using robot technology. We have developed Waseda Kyotokagaku Airway No.4 (WKA-4) as a novel training simulator for airway management. This robot reproduces several different patients with actuators. For instance, this robot has a unique mechanism in its temporomandibular joint that consists of a set of warm gears and force sensors, hence reproduces a patient with TMJ disorder. This robot also has the tongue that is able to change its shape using air pressure, hence reproduces the difficulty of airway management. We then asked the medical doctors to evaluate the robot using a questionnaire and confirmed that WKA-4 had enough property to use in the training of anesthesiologists.

The emerging field of medical robotics is aimed at introducing intelligent tools. More recently, thanks to the innovations in robot technology (RT), advanced medical training systems have been introduced to improve the skills of trainees. The principal challenges of developing efficient medical training systems is that they must simulate real-world conditions of the task, provide objective assessments of training progress, and provide useful feedback to trainees. So far, many medical training systems have been developed
however, those training system do not fulfill the three conditions of the Active Training system. For the proof of concept of an effective Active Training system, we proposed WKA-4 (Waseda Kyotokagaku Airway No.4) which satisfies all of the requirements of the Active Training system. In this paper, we present the hardware configuration of the WKA-4 briefly, which has 11 embedded actuators and 44 embedded sensors, and simulates real-world condition of the task. In addition, in order to verify the usefulness of feedback of the WKA-4 for medical training, a set of the experiments were carried out to a doctor group and two novice groups. One novice group is provided by the feedback of the embedded sensors of the WKA-4 while the other novice group is not. From the comparisons of the results of the experiments, we verify the effectiveness of our proposed Active Training system. © 2012 IEEE.

Laparoscopy is a very popular surgical technique for abdominal operations. Due to the difficulties in using the laparoscopes, the surgeons need an extensive training to acquire the right locomotive skill and perform operations. Usually, the training is performed with dry boxes with simple and repetitive exercises, like the peg-board, in which a trainee uses the instruments to move sequentially a set of rubber O rings positioned inside pegs. However, even if the dry box is a good method to train the dexterity of a trainee, it does not include the mental stress, that could be significant during the operation in the actual Operating Room (OR). In this paper we present the comparison results during a peg-board training without and with induced mental stress. In particular, the stress has been introduced by a proposed protocol adaptively setting a countdown with noisy alarm for the last 60s of the exercise. We compared the results by a biomechanical analysis using surface Electromyography, showing that the induced stress situation revealed a significant larger activation of the arms and shoulders muscles.

This paper describes the development of a new expressive robotic head for the bipedal humanoid robot. Facial expressions of our old robotic head have low facial expression recognition rate and in order to improve it we asked amateur cartoonists to create computer graphics (CG) images. To realize such expressions found in the CGs, the new head was provided with 24-DoFs and facial color. We designed compact mechanisms that fit into the head, which dimensions are based on average adult Japanese female size. We conducted a survey with pictures and videos to evaluate the expression ability. Results showed that facial expression recognition rates for the 6 basic emotions are increased compared to the old KOBIAN's head. © 2012 IEEE.

In this paper we describe how a humanoid robot can learn a representation of its own reachable space from motor experience: a Reachable Space Map. The map provides information about the reachability of a visually detected object (i.e. a 3D point in space). We propose a bio-inspired solution in which the map is built in a gaze-centered reference frame: the position of a point in space is encoded with the motor configuration of the robot head and eyes which allows the fixation of that point. We provide experimental results in which a simulated humanoid robot learns this map autonomously and we discuss how the map can be used for planning whole-body and bimanual reaching.

The results of the neuroscientific research show that humans tend to stabilize the head orientation during locomotion. In this paper we describe the implementation of inverse kinematics based head stabilization controller on the humanoid platform. The controller uses the IMU feedback and controls neck joints in order to align the head orientation with the global orientation reference. Thanks to the method, we can decouple the orientational motion of the head from the rest of the body. This way stabilized head becomes better platform for proprioceptive sensory apparatus, such as cameras or IMU. In the paper we present three experiments which prove that the method has good performance in damping both, high and low frequency motion of the head. We also prove that the proposed controller improves the stability of the tracked goal point on the image of in-built camera.

This paper describes a walking stabilization control based on gait analysis for a biped humanoid robot. We have developed a human-like foot mechanism mimicking the medial longitudinal arch to clarify the function of the foot arch structure. To evaluate the arch function through walking experiments using a robot, a walking stabilization control should also be designed based on gait analysis. Physiologists suggest the ankle, hip and stepping strategies, but these strategies are proposed by measuring human beings who are not "walking" but "standing" against force disturbances. Therefore, first we conducted gait analysis in this study, and we modeled human walking strategy enough to be implemented on humanoid robots. We obtained following two findings from gait analysis: i) a foot-landing point exists on the line joining the stance leg and the projected point of CoM on the ground, and ii) the distance between steps is modified to keep mechanical energy at the landing within a certain value. A walking stabilization control is designed based on the gait analysis. Verification of the proposed control is conducted through experiments with a human-sized humanoid robot WABIAN-2R. The experimental videos are supplemented.

This paper describes a walking stabilization control on a soft ground based on gait analysis for a biped humanoid robot. There are many studies on gait analysis on a hard ground, but few physiologists analyze the walking ability of human beings on a soft ground. Therefore, we conducted anthropometric measurement using VICON motion capture system on a soft ground. By analyzing experimental results, we obtained three findings. The first finding is that step height tends to increase to avoid tripping on a soft ground but there are no significant differences in step length and step width. The second finding is that although the CoM amplitude increases in the vertical direction on a soft ground, there are no significant differences in the CoM trajectories in the lateral direction. The last finding is that the head is stabilized during walking not only on a hard ground but also on a soft ground. Based on these findings, we developed a novel walking stabilization control to stabilize the CoM motion in the lateral direction on a soft ground. Verification of the proposed control is conducted through experiments with a human-sized humanoid robot WABIAN-2R. The experimental videos are supplemented.

The neuroscientific research shows that humans tend to stabilize their head orientation, while accomplishing a locomotor task. In order to replicate head movement behaviors found in human walk it is necessary and sufficient to be able to control the orientation (roll, pitch and yaw) of the head in space. The described behaviors can be replicated by giving suitable references to the head orientation. Based on these principles, a model based on an inverse kinematics controller has been designed. In this paper we introduce implementation of the model on a humanoid platform. Along we present results of two sets of experiments performed to verify two aspects of the proposed model. The results prove that the model can be used to efficiently stabilize the head's orientation.

In this work we propose an adaptive model for the head stabilization based on a feedback error learning (FEL). This model is capable to overcome the delays caused by the head motor system and adapts itself to the dynamics of the head motion. It has been designed to track an arbitrary reference orientation for the head in space and reject the disturbance caused by trunk motion. For efficient error learning we use the recursive least square algorithm (RLS), a Newton-like method which guarantees very fast convergence. Moreover, we implement a neural network to compute the rotational part of the head inverse kinematics. Verification of the proposed control is conducted through experiments with Matlab SIMULINK and a humanoid robot SABIAN. © 2012 IEEE.

The surface electromyography (sEMG) signal is affected by different sources of noises: current technology is considerably robust to the interferences of the power line or cable motion artefacts, but still there are many limitations in denoising the baseline. In this paper, we introduce a new technique, named baseline adaptive denoising algorithm (BADA), for denoising the sEMG signal by wavelet thresholding procedure. In particular, the thresholds are estimated using the same baseline signal with fixed and adaptive techniques. Eventually, we verify that the proposed adaptive method performs better than the standard Donoho technique and different variations, in term of noise cancellation and distortion of the signal, quantified by a new suggested indicator of the denoising quality. Copyright © 2012 Inderscience Enterprises Ltd.

In the last years there has been increasing interest on Inertial Measurement Units (IMUs) in several fields, because they can provide a measurement of the orientation, velocity, and acceleration at low cost with high performance. The main reason of the low cost is the possibility to find inertial sensors, as accelerometers, gyroscopes and magnetometers, based on Micro-Electro-Mechanical Systems (MEMS) made by silicon, with further advantages of small dimensions and mass production from the main semiconductor suppliers. In this paper, we present the development of the ultra miniaturized wireless IMU, WB-4 (Waseda Bioinstrumentation number 4), with a 3-axis accelerometer, 3-axis gyroscope and 3-axis magnetometer. Additionally, we illustrate, together with results, the algorithms used for the data filtering and calibration, with particular emphasis on a new methodology for the online calibration of the digital magnetometer.

This paper presents the performance evaluation of our wireless miniature Inertial Measurement Unit (IMU) WB-4 by compared with the Vicon motion capture system. In particular, a magnetic field calibration method is introduced to improve the sensor orientation estimate accuracy.
The WB-4 IMU primarily contains a motherboard for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The motherboard is provided with a 32-bit microcontroller and 3-axis miniaturized MEMS accelerometer, 3-axis gyroscope and 3-axis magnetometer to estimate the sensor orientation based on an extended Kalman filter algorithm. In our previous research of WB-4 IMU performance evaluation, the factory calibration parameters of the magnetometer were used for the sensor fusion, which resulted in a higher error on the yaw angle in respect to roll and pitch. This study presents a magnetic calibration method for overcoming that limitation. The experimental results showed that the wireless WB-4 IMU could achieve better orientation performance in all the directions after the implementation of the magnetic calibration method. The yaw angle accuracy was significantly improved from previous error 5.46 degree to 1.77 degree.

In this paper, we describe a human gesture recognition system developed to enable a robot instrument player to recognize the variations in tempo and in articulation dictated by a conductor's movements and accordingly adapt its performance. The enhanced interaction ability would allow the partner musicians, as well as the conductor, to better appreciate a joint musical performance, because of the complete naturalness of the interaction. In addition, the possibility for the robot to change its performance parameters according to the conductor directions, thus being synchronized with all the other human musicians, would lead to an improvement in the overall musical performance.

A device for the gait analysis during a long-distance walking is important for the correct assessment of patients during the rehabilitation. This device should be able to measure all gait parameters in a single unit. In addition, it is required that the measurement system is not spatially constrained. In our group, we have been developing a new wireless system, namely WB-4R, composed of Inertial Measurement Units, to be used in rehabilitation centers for gait analysis that is cheap, small, and relatively maintenance-free. This paper presents the results of a pilot study conducted with healthy subjects. The system was able to detect the gait phase and provide frequency analysis of the angular velocity and acceleration of the lower limbs.

In this paper, we describe the mechanical design system implemented to enable a robot flute player to enhance the expressiveness of its performance, reproducing the different musical articulations with the available features of the instrument. In addition, the robot has been equipped with a Human Gesture Recognition system to recognize the real-time variations in tempo, dynamics, and articulation dictated by the conductor's movements. The possibility for the robot to change its performance parameters according to the conductor directions, thus adding expression to its performance while being synchronized with all the other human musicians, would lead to an improvement in the overall joint musical performance.

This paper describes a walking stabilization control on a soft ground based on gait analysis for a humanoid robot. There are many researches on gait analysis on a hard ground, but few scientists analyze the walking ability of human beings on a soft ground. Therefore, we conducted anthropometric measurement using a motion capture system on a soft ground. By analyzing experimental data, we obtained two findings. The first finding is that although there are no significant differences in step width and step length, step height tends to increase to avoid the collision between the feet and a soft ground. The second finding is that there are no significant differences in the lateral CoM trajectories but the vertical CoM amplitude increases when walking on a soft ground. Based on these findings, we developed a walking stabilization control to stabilize the CoM motion in the lateral direction on a soft ground. Verification of the proposed control is conducted through experiments with a human-sized humanoid robot WABIAN-2R. The experimental videos are supplemented.

The results of the neuroscientific research show that humans tend to stabilize the head orientation during locomotion. In this paper we describe the implementation of inverse kinematics based head stabilization controller on the humanoid platform. The controller uses the IMU feedback and controls neck joints in order to align the head orientation with the global orientation reference. Thanks to the method, we can decouple the orientational motion of the head from the rest of the body. This way stabilized head becomes better platform for proprioceptive sensory apparatus, such as cameras or IMU. In the paper we present three experiments which prove that the method has good performance in damping both, high and low frequency motion of the head. We also prove that the proposed controller improves the stability of the tracked goal point on the image of in-built camera.

This paper describes the development of a new expressive robotic head for the bipedal humanoid robot. Facial expressions of our old robotic head have low facial expression recognition rate and in order to improve it we asked amateur cartoonists to create computer graphics (CG) images. To realize such expressions found in the CGs, the new head was provided with 24-DoFs and facial color. We designed compact mechanisms that fit into the head, which dimensions are based on average adult Japanese female size. We conducted a survey with pictures and videos to evaluate the expression ability. Results showed that facial expression recognition rates for the 6 basic emotions are increased compared to the old KOBIAN's head. © 2012 IEEE.

We describe an interactive learning strategy that enables a humanoid robot to build a representation of its workspace: we call it a Reachable Space Map. The robot learns this map autonomously and online during the execution of goal-directed reaching movements; reaching control is based on kinematic models that are learned online as well. The map can be used to estimate the reachability of a fixated object and to plan preparatory movements (e.g. bending or rotating the waist) that improve the effectiveness of the subsequent reaching action. Three main concepts make our solution innovative with respect to previous works: the use of a gaze-centered motor representation to describe the robot workspace, the primary role of action in building and representing knowledge (i.e. interactive learning), the realization of autonomous online learning. We evaluate our strategy by learning the workspace of a simulated humanoid robot and we show how this knowledge can be exploited to plan and execute complex actions, like whole-body bimanual reaching.

Communication between humans and robots is a very critical step for the integration of social robots into society. Emotion expression through a robotic face is one of the key points of communication. Despite the most recent efforts, no matter how much expression capabilities improve, facial expression recognition is often hampered by a cultural divide between subjects that participate in surveys. The purpose of this work is to take advantage of the 24 degrees of freedom head of the humanoid social robot KOBIAN-R for making it capable of displaying different versions of the same expressions, using face and neck, in a way that they are easy to understand for Japanese and for Western subjects. We present a system based on relevant studies of human communication and facial anatomy, as well as on the work of illustrators and cartoonists. The expression generator we developed can be adapted to specific cultures. Results confirmed the in-group advantage, showing that the recognition rate of this system is higher when the nationality of the subjects and the cultural characterisation of the shown expressions are coincident. We conclude that this system could be used, in future, on robots that have to interact in a social environment, with people with different cultural background. © 2012 Springer-Verlag.

Human-robot communication is a very important aspect in the field of Humanoid Robotics. Non-verbal communication is one of the components that make interaction natural. However, despite the most recent efforts, robots still can show only limited expression capabilities. The purpose of this work is to create a facial expression generator that can be applied to the new 24 DoF head of the humanoid robot KOBIAN-R. In this paper, we present a system based on relevant studies of human communication and facial anatomy, adapted to the specific robotic face. It makes use of polynomial classifiers and is able to produce over 600 thousands of facial cues combinations, together with appropriate neck movement. Results showed that the recognition rate of expressions produced by this system is comparable to the rate of recognition of the most common facial expressions. We conclude that our system can successfully improve the communication capabilities of the robot KOBIAN-R, and that there is potential for using it to implement more complex interaction. © 2012 IEEE.

Human-Robot Interaction is one of the biggest challenges in Humanoid Robotics. Interaction can be carried out through different channels, as humans can communicate through complex languages, including the use of non-verbal communication. Specifically, facial expressions are important for conveying emotions and communication intentions. Several humanoid robots can already perform a certain set of expressions, but their capabilities are somewhat limited and as a result, interaction is not natural. One aspect that could help robots being perceived as real is asymmetry. That is why in this paper we perform an evaluation study of symmetrical and asymmetrical facial expressions of the humanoid robot KOBIAN-R These expressions are made by a generator based on relevant studies of facial anatomy and non-verbal communication and on the work of illustrators and cartoonists. Survey results confirmed the effectiveness of the generator and the importance of asymmetry. We conclude that using this system, robot communication capabilities improve, making possible the development of more advanced interaction in the future. © 2012 IEEE.

The ultrasound diagnosis of the carotid artery is one of the most common non-invasive methods to detect early stage heart and cerebrovascular diseases. However, the precision and repetitiveness of the probe positioning depend exclusively on the operator's skills and dexterity. For this purpose, we propose the development of a robot assisted system to enhance the accuracy and repetitiveness of the probe positioning to measure the wave intensity (WI) index. In this paper, the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement Robot System No. 2 Refined (WTA-2R) is presented. The WTA-2R consists of a conventional ultrasound diagnosis system, a 6-DOFs parallel link slave manipulator, a 6-DOFs serial link passive arm, and a master device. Experiments were carried out to verify its effectiveness in terms of accuracy and required time to perform the task. From the experimental results, the positioning accuracy and reduction of required time were confirmed. (C) 2011 Elsevier Ltd. All rights reserved.

Our research is related to the development of an anthropomorphic saxophonist robot which reproduced the human organs involved during the saxophone playing. This research approach aims in understanding the human motor control from an engineering point of view and enabling the communication between humans and robots in musical terms. In a previous research, we have presented the Waseda Saxophonist Robot No. 2 (WAS-2) which improved the design of the lip and finger mechanisms. In addition, a feed-forward air pressure with dead-time compensation and an overblowing correction controller were implemented. However, the range of pressure was too limited to reproduce dynamic effects of the sound (i.e. decrescendo, etc.), a delay on the response of the finger mechanism was detected (due to the use of a wire-driven mechanism) and deviations on the pitch during the saxophone playing were observed. Therefore; in this paper, we present the Waseda Saxophonist Robot No. 2 Refined (WAS-2R). In particular the shape of the oral cavity has been re-designed to increase the sound pressure range and potentiometers were embedded on the fingers to reduce the dynamic delay response of the wire-driven mechanism. In addition, a Pressure-Pitch Controller has been implemented to reduce the deviation of the sound pitch by implementing a feedback error learning algorithm for a Multiple-Input Multiple-Output system. A set of experiments were proposed to verify the effectiveness of the re-designed mechanisms and the improved control strategy. From the experimental results, we could confirm the improvements to extend the sound pressure range to reproduce the decrescendo effect, to reduce the response delay from the finger mechanism as well as the deviations on the sound pitch.

The surface Electromyography (sEMG) signal is affected by different sources of noises: current technology is considerably robust to the interferences of the power line or the cable motion artifacts, but still there are many limitations with the baseline and the movement artifact noise. In particular, these sources have frequency spectra that include also the low-frequency components of the sEMG frequency spectrum; therefore, a standard all-bandwidth filtering could alter important information. The Wavelet denoising method has been demonstrated to be a powerful solution in processing white Gaussian noise in biological signals. In this paper we introduce a new technique for the denoising of the sEMG signal: by using the baseline of the signal before the task, we estimate the thresholds to apply to the Wavelet thresholding procedure. The experiments have been performed on ten healthy subjects, by placing the electrodes on the Extensor Carpi Ulnaris and Triceps Brachii on right upper and lower arms, and performing a flexion and extension of the right wrist. An Inertial Measurement Unit, developed in our group, has been used to recognize the movements of the hands to segment the exercise and the pre-task baseline. Finally, we show better performances of the proposed method in term of noise cancellation and distortion of the signal, quantified by a new suggested indicator of denoising quality, compared to the standard Donoho technique.

Performing laparoscopic surgery requires several skills which have never been required for conventional open surgery, surgeons experience difficulties in learning and mastering these techniques. Various training methods and metrics have been developed in order to assess and improve surgeon's operative abilities. While these training metrics are currently widely being used, skill evaluation methods are still far from being objective in the regular laparoscopic skill education.
This paper proposes a methodology of defining a model to objectively evaluate surgical performance and skill expertise in the routine laparoscopic training course. Our approach is based on the processing of kinematic data describing the movements of surgeon's upper limbs. An ultra-miniaturized wearable motion capture system (Waseda Bioinstrumentation system WB-3), therefore, has been developed to measure and analyze these movements. The skill evaluation model was trained by using the subjects' motion features acquired from WB-3 system and further validated to classify the expertise levels of the subjects with different laparoscopic experience. An experiment for training fundamental laparoscopic psychomotor skill was elaborated by using laparoscopic box trainer. Preliminary results show that, the proposed methodology can be efficiently used both for quantitative assessment of surgical ability, and for the discrimination between expert surgeons and novices.

:This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized inertial measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated.

This paper describes an avoidance behavior against unknown forces acting from outside the system on a biped vehicle. External forces that act on a biped vehicle can be divided into two categories: disturbances from the rider of the vehicle and disturbances from outside the system. Disturbances from the rider are measured by a force sensor placed between the rider's seat and the pelvis, while disturbances from outside the system are estimated from zero moment point (ZMP) errors. To guarantee walking stability, the waist position is adjusted to match the measured ZMP to the reference ZMP and the position of the landing foot is adjusted such that the waist trajectory does not diverge. On implementing the developed method on the human-carrying biped robot in an experimental setup, the robot could realize a stable walk even while subjected to unknown external forces in the environment. On applying a pushing force to the walking robot, the robot moved in the pushed direction and away from the source of the externally generated forces. On pushing the robot that was walking forward, the robot stopped moving forward and avoided getting closer to the source of the externally generated forces. We confirmed the effectiveness of the proposed control through these experiments. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2011

In recent years advanced robotic technology has seen more use in the medical field to assist in the development of efficient training systems. Such training systems must fulfill the following criteria: they must provide quantitative information, must simulate the real-world conditions of the task, and assure training effectiveness. We developed Waseda Kyotokagaku Airway series to fulfill all of those requirements. The WKA series we had developed does not consider external appearance such as patient skin, or internal appearance such as the pharynx, larynx, and esophagus. Moreover, the tongue mechanism of the previous system can not precisely measure the force applied by medical devices and cannot simulate muscle stiffness. In addition, the mandible mechanism of the previous system could not adequately reproduce various airway difficulties or apply force control. For these reasons, we propose the WKA-4, which has high-fidelity simulated human anatomy, and we have improved the mechanism over the previous system. We have also attached a lung to the proposed system to improve simulation of the real-world conditions of the task. In this paper, we present how to design several organs with various embedded sensors and actuators, for a conventional patient model with high-fidelity simulated human anatomy. We also present the control system for the WKA-4. Finally, we present a set of experiments carried out using doctors as subjects, and they gave their valuable opinions about our system.

Many patients suffer from swallowing disorders (dysphagia). There are many treatments for these disorders, such as swallowing therapy, surgery, and dietary modification. In our study, we focuse on dietary modification, a common approach. Normally, the swallowing is affected by food bolus properties such as hardness, stickiness and rheological characteristics, and dietary modifications can prevent swallowing disorder patients from suffering dysphagia (aspiration), as well as promote good nutrition. Based on these facts, our goal is to find foods which do not cause dysphagia, and develop food for swallowing disorder patients accordingly. Therefore, we are proposing an in-vitro Dynamic VFSS (Video Fluorographic Swallowing Study) simulation system which uses advanced robotics technology to mimic the dynamic process of swallowing and monitors the status and movement of the food bolus inside the system, for objective evaluation of the swallowing process. The dynamic VFSS simulation system consists of a head, mandible, neck, tongue, pharynx, and larynx which reproduce human anatomy. It is driven by 16 actuators with wire driving mechanisms. In this paper, we will present the dynamic VFSS simulation unit in detail. In addition, we will detail a set of the experiments carried out to determine whether food bolus properties can affect dysphagia or not. To observe the movement of the food bolus, we use a Video Fluoroscopy (VF) unit. The results of the experiments show that thickened boluses have a tendency to leave residue in the epiglottic vallecula. In contrast, liquids cause less residue, and increase the risk of dysphagia (aspiration). Moreover, this study shows that the frontal image, as well as the lateral image, is important for evaluating residual food in the oral-pharyngeal space.

The Simulation Model which can visualize the shape of commercial colonoscope is proposed. This model uses kinematic chain which approximates the shape of colonoscope by serially connected multiple joint-link pairs. As the input to the model, orientation information is used. Orientation information is extracted from the Sensor Network. The sensor network consists of connecting a number of sensor units with CAN bus. Each sensor unit also has two kinds of sensor: triad of accelerometer and triad of magnetometer. Roll and pitch angle are estimated based on the accelerometer signals. Yaw angle is estimated based on the magnetometer signals. By using kinematic chain model and orientation as input, we estimate the key points which are positions of sensor units on the colonoscope. Then, we implement spline interpolation to find the intermediate points which constitutes the shape of colonoscope. We made experiment in order to check whether model has enough accuracy. Firstly, we compared estimated curve with sine curve which is used as a ground truth. Secondly, we investigated the effect of number of sensor on the accuracy. Final result says that it has enough estimation ability.

3D Visualization method of shape of flexible colonoscopy in simulated computing environment is proposed. Signals from sensor network are used to calculate the orientation of the body of each sensor. Position of each sensor is estimated from the orientation using assumption of forward kinematics in robotics. This data are then interpolated with curve fitting method to give natural impression of shape to surgeon who are watching monitor. The resulting simulated curve shows that motion of shape of colonoscopy can be simulated at it is.

This research proposes to design and develop a novel robot involved in the general and famous animal experimental method called Social Interaction Test (SIT). Aiming at increased movement range of the waist and improved interoperability, we have developed a novel small animaroid robot WR-4 (Waseda Rat No.4). The waist of WR-4 endowed with a multi-bendable 6-bar linkage mechanism makes the robot able to rotate around ±130° horizontally, meeting required movement range. Integrating with a 4-bar linkage mechanism in the neck, this 6-bar linkage mechanism achieves the bending posture as living rats, allowing the imitation of behavior such as rotating. Furthermore, ultrasonic motors (USM) used to drive forelegs greatly reduce the weight of upper body, resulting in quicker acting of rearing behavior. WR-4 consists of 10 active DOFs (two 1-DOF wheels for locomotion, two 2-DOF forelegs for interaction, one 1-DOF neck for swing, one 2-DOF waist for rearing and body grooming and one 1-DOF reserved for tail) and 2 passive DOFs in the paws. The evaluation tests on motion performance show that WR-4 could act both rearing (reaching 60°) and rotating (reaching ±100° respectively) behaviors approximately 0.1s quicker than mature rats. Preliminary SIT between WR-4 and mature rats have been conducted strictly following psychological rules. Experimental results reveal that the frequencies of rearing behavior in rats were increased significantly when WR-4 reared periodically, and the activities of rats were decreased after WR-4 reared. © 2011 IEEE.

Up to now, there are different kinds of robot-assisted ultrasound diagnostic systems proposed in the last decade. However, the compensation of the ultrasound probe position according to the patient movement is still one of the most important and useful functions required for those systems. For this purpose, in this research, we aim at developing an automated diagnostic system for the measurement of the wave intensity which is usually measured at the common carotid artery. In particular, in this paper, we focus on proposing a robust visual servoing method for tracking out-of-plane motion for a robot-assisted medical ultrasound diagnostic system by using a conventional 2D probe. A robotic device which manipulates the ultrasound probe firstly scans a small area around the target position and records several B-mode images at a regular interval. In order to track the out-of-plane motion, an inter-frame block matching method has been proposed and implemented on the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement System No. 2 Refined (WTA-2R). A set of experiments was proposed to verify the effectiveness of the proposed method. From the experimental results, we could confirm its robustness while doing the task with real human tissues.

In this paper we propose the basic concept of a tele-presence system for two (or more) anthropomorphic robots located in remote locations. As one robot interacts with a user, it acquires knowledge about the user's behavior and transfers this knowledge to the network. The robot in the remote location accesses this knowledge and according to this information emulates the behavior of the remote user when interacting with its partner. © 2011 IEEE.

This paper describes a fast turning method for a humanoid robot by using slipping motion with both feet. The humanoid robot, WABIAN-2R, has achieved human-like walking with heel contact and toe off motions by using a human-like foot mechanism with a passive toe joint. The human-like foot enables a robot to turn by using slipping motion between the feet and the ground because it can switch ground contact conditions such as heel contact, sole contact and toe contact. To realize a slipping turn, we develop an attitude control. Verification of the proposed method is conducted through experiments with a biped humanoid robot WABIAN-2R. WABIAN-2R realized a quick turn by using slipping motion with both feet. We also confirmed that the energy consumption of a slipping turn is less than that of a stepping turn.

A four degrees of freedom (DoF) waist and trunk mechanism, as well as human-like foot, enable the humanoid robot WABIAN-2R to perform human-like walk with stretched knees, and heel-contact and toe-off gait phases. The inverse kinematics (IK) method, used in the present system, requires specification of not only task space reference trajectories, but also reference trajectories for all redundant DoFs. In this paper, we propose a novel, unified inverse kinematics method significantly simplifying the pattern generation. The method enables generation of the above described gait by specifying only the task space trajectories. We divide the forward locomotion task into subtasks with different priorities and combine them in the single IK equation. We also perform experiments in simulation environment as well as on WABIAN-2R, which prove that the method can be used to calculate IK for human-like gait. The equation evaluated in this paper is applied to the forward locomotion task, however it can be easily modified to perform other tasks on humanoid robots with different kinematic structures.

This research proposes to design and develop a novel robot involved in the general and famous animal experimental method called Social Interaction Test (SIT). Aiming at increased movement range of the waist and improved interoperability, we have developed a novel small animaroid robot WR-4 (Waseda Rat No.4). The waist of WR-4 endowed with a multi-bendable 6-bar linkage mechanism makes the robot able to rotate around ±130° horizontally, meeting required movement range. Integrating with a 4-bar linkage mechanism in the neck, this 6-bar linkage mechanism achieves the bending posture as living rats, allowing the imitation of behavior such as rotating. Furthermore, ultrasonic motors (USM) used to drive forelegs greatly reduce the weight of upper body, resulting in quicker acting of rearing behavior. WR-4 consists of 10 active DOFs (two 1-DOF wheels for locomotion, two 2-DOF forelegs for interaction, one 1-DOF neck for swing, one 2-DOF waist for rearing and body grooming and one 1-DOF reserved for tail) and 2 passive DOFs in the paws. The evaluation tests on motion performance show that WR-4 could act both rearing (reaching 60°) and rotating (reaching ±100° respectively) behaviors approximately 0.1s quicker than mature rats. Preliminary SIT between WR-4 and mature rats have been conducted strictly following psychological rules. Experimental results reveal that the frequencies of rearing behavior in rats were increased significantly when WR-4 reared periodically, and the activities of rats were decreased after WR-4 reared. © 2011 IEEE.

This paper presents the design and development of a bio-inspired mobile robot called WR-3 (Waseda Rat no. 3). The purpose of the robot is to work as an experimental tool to study social interaction between rats and robots. According to the results of the analysis of the motion of rats, their behavior can be divided into two phases: movement and interaction. Therefore, a novel hybrid mechanism that uses wheels during the movement phase and legs while interacting has been designed to actuate WR-3. Consequently, the robot can move at a high speed using its wheels, and reproduce the rat&apos;s interaction behavior using its legs and other parts. Based on body structure of a mature rat, WR-3 has been designed with similar dimensions and shape as a mature rat, and the quality of the shape imitation has been verified by the experiments of a rat&apos;s interestingness to the robot and stuffed rat. Evaluation experiments show that WR-3 is capable of reproducing a rat&apos;s actions such as chasing, rearing, grooming, mounting, etc., similar to a real rat. Furthermore, preliminary social interaction tests with living rats reveal that WR-3 is to some extent able to evoke natural reactions form a real rat and is therefore able to perform a certain level of realistic interaction. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2011

In this paper we present a general strategy for the calculation of the effective Center of Mass (CoM) of humanoid robots, allowing the reduction of the error between the virtual robot model and the real platform. The method is based on an algorithm that calculates the real position of the CoM of a biped humanoid robot using only 2 force/torque sensors located on the feet of the robot. By means of this algorithm, it is possible to reduce the gap between the real and the virtual posture of the robot and consequently the errors between the ZMP trajectory calculated by the offline pattern generator and the ZMP trajectory calculated by the real-time pattern generator of the humanoid robot. Thus, the influence of the real-time control in the static and dynamic balance of a humanoid platform is minimized. Experimental results using SABIAN platform are provided to validate the proposed method. The results support the applicability of the method to more complex systems. © 2011 IEEE.

Humanoid robots are becoming an important factor for the future work. Future planes are made for the use of humanoid robots for space and planetary exploration application. The development of humanoid robot to work in such environment for the purpose of human assisting is becoming highly demanded. The challenge of developing a bipedal robot to walking on other planets and moons is really high due the different in gravity compare to earth. The difference in the gravity might have a great effect on the robot locomotion. In order to know this effect some basic study needed to be conducted. This research studies the effect of different gravity on the locomotion. The approach for dealing for the different gravity is purposed in this study. © 2011 IEEE.

We present an autonomous goal-directed strategy to learn how to control a redundant robot in the task space. We discuss the advantages of exploring the state space through goal-directed actions defined in the task space (i.e. learning by trying to do) instead of performing motor babbling in the joints space, and we stress the importance of learning to be performed online, without any separation between training and execution. Our solution relies on learning the forward model and then inverting it for the control
different approaches to learn the forward model are described and compared. Experimental results on a simulated humanoid robot are provided to support our claims. The robot learns autonomously how to perform reaching actions directed toward 3D targets in task space by using arm and waist motion, not relying on any prior knowledge or initial motor babbling. To test the ability of the system to adapt to sudden changes both in the robot structure and in the perceived environment we artificially introduce two different kinds of kinematic perturbations: a modification of the length of one link and a rotation of the task space reference frame. Results demonstrate that the online update of the model allows the robot to cope with such situations. © 2011 IEEE.

Personal robots and Robot Technology (RT)-based assistive devices are expected to play a substantial role in our society largely populated by the elderly
they will play an active role in joint works and community life with humans. In particular, these robots are expected to play an important role in the assistance of the elderly and disabled people during normal Activities of Daily Living (ADLs). To achieve this result, personal robots should better be capable of making emotional expressions like human. In this perspective we developed a whole body bipedal humanoid robot named KOBIAN that is capable of expressing humanlike emotions. In this paper we present the development and evaluations of KOBIAN.

Since 1990, at Waseda University the development on the Anthropomorphic Flutist Robot has been focused on mechanically reproducing the physiology of the organs involved during the flute playing (i.e. lungs, lips, etc.) and implementing basic cognitive capabilities to interact with flutist beginners. As a results of the research efforts done until now, the Waseda Flutist Robot is considered to play the flute nearly similar to the performance of a intermediate human player. However, we consider that in order to extend the interaction capabilities of the flutist robot with musical partners, further research efforts should be done. In this paper, we propose as a long-term goal to enable the flutist robot to interact more naturally with musical partners on the context of a Jazz band. For this purpose a Musical-Based Interaction System (MbIS) is proposed to enable the robot the process both visual and aural cues coming throughout the interaction with musicians. In particular, in this paper, the details of the implementation of the visual tracking module on the Waseda Flutist Robot No. 4 Refined IV (WF-4RIV) is presented. The visual tracking module is composed by two levels of interaction: basic (visual interface for the musician based on controlling virtual buttons and faders) and advanced (instrument tracking system so that the robot can process motion gestures performed by the musical partner in real-time which are then directly mapped into musical parameters of the performance of the robot). The experiments carried out were focused in verifying the effectiveness and usability of the proposed levels of interaction. In particular, we focused on determining how well our the WF-4RIV dynamically changes musical parameters while interacting with a human player. From the experimental results we observed that the physical constraints of the robot play an important role during the interaction. Although further improvements should be done to overcome such constrains, we expect that the interaction experience may become more natural. © 2010 Springer Science+Business Media, LLC.

Our research aims to develop an anthropomorphic saxophone-playing robot; as an approach to understand the human motor control from an engineering point of view. In this paper, we present the Waseda Saxophonist Robot No. 2 (WAS-2) which is composed of 22 degrees of freedom (DOF). In particular, he functioning of the lips, fingers, tongue, oral cavity and lungs have been mechanically simulated to enable WAS-2 to play an alto saxophone. Furthermore, in order to ensure the accuracy of the air pressure control, a feed-forward control system with dead time compensation has been implemented. A set of experiments were carried out to verify the effectiveness of the proposed system. From the experimental results, the range of sound pressure was increased and the air pressure control was improved.

This paper describes an online walking pattern generation method for biped humanoid robots which is based on a preview control method. Depending on the walking parameters, a 3-step pattern and reference ZMP are generated, and one step in the pattern is selected for walking. If another 3-step pattern is created, it will connect with the previous step using linear interpolation. This pattern generation method is able to deal with forward, sideward and forward-sideward mixed walking. In order to confirm the pattern generation method, various walking simulations are conducted using MATLAB/Simulink and ADAMS.

Even though the market size is still small at this moment, applied fields of robots are gradually spreading from the manufacturing industry to the others as one of the important components to support an aging society. For this purpose, the research on human-robot interaction (HRI) has been an emerging topic of interest for both basic research and customer application. The studies are especially focused on behavioral and cognitive aspects of the interaction and the social contexts surrounding it. As a part of these studies, the term of oroboethicso has been introduced as an approach to discuss the potentialities and the limits of robots in relation to human beings. In this article, we describe the recent research trends on the field of humanoid robotics. Their principal applications and their possible impact are discussed.

In the medical literature, the ultrasound diagnosis is a quite well user-friendly method due to its non-invasiveness, portability and real-time imaging capabilities. Recently, some fatigue issues (including musculoskeletal injuries) with sonographers have been reported. Most of those issues are mainly due to the physical stress on the sonographers during their considerably long time task. During the diagnosis, the sonographers usually hold their wrist without touching the patients. Moreover, they are sometimes required to apply a force for the probe to push abdomen of the patients in order to obtain clearer ultrasound image. Therefore, our research aims in developing a probe supporting robot to reduce the fatigue of sonographers during the abdominal diagnosis. In this paper, we describe the design of the Waseda-Tokyo Women's Medical-Aloka System No. 2 (WTA-2) which is composed of an ultrasound diagnosis system, an actuated 3-DOFs robot arm with two different interchangeable end-effectors. One is for power assist of applied force, and the other is for supporting sonographer's wrist. The design of the robot, a force sensing method using photo sensors and the control of the robot are detailed. A set of experiments were carried out in order to verify the effectiveness of the proposed system to support sonographers while performing the diagnosis.

Since 2007, the research on the anthropomorphic saxophonist robot at Waseda University aims in understanding the human motor control from an engineering point of view as well as an approach to enable the interaction with musical partners. As a result of our research, last year we have introduced the Waseda Saxophonist Robot No. 1 (WAS-1), composed of 15-DOFs that reproduced the lips (1-DOF), tonguing (1-DOF), oral cavity, lungs (2-DOF) and fingers (11-DOFs). However, even that the mouth mechanism of WAS-1 was useful in order to adjust the pitch of the saxophone sound, the range of sound pressure was too narrow. Thus, no dynamic effects of the sound can be reproduced (i.e. crescendo and decrescendo). Moreover, the finger mechanism was designed only to play from C3-C#5. On the other hand, a cascade feedback control system has been implemented in the WAS-1; however, a considerable delay in the attack time to reach the desired air pressure was detected. Therefore, in this paper, the Waseda Saxophone Robot No. 2 (WAS-2) which is composed by 22-DOFs is detailed. The lip mechanism of WAS-2 has been designed with 3-DOFs to control the motion of the lower, upper and sideway lips. In addition, a human-like hand (16 DOF-s) has been designed to enable to play all the keys of the instrument. Regarding the improvement of the control system, a feed-forward control system with dead-time compensation has been implemented to assure the accurate control of the air pressure. A set of experiments were carried out to verify the mechanical design improvements and the dynamic response of the air pressure. As a result, the range of sound pressure has been increased and the proposed control system improved the dynamic response of the air pressure control.

The Waseda Flutist Robot WF-4RIV is a humanoid robot that is able to imitate a human flute performance. In the recent years the mechanical construction of the robot has been improved, so that the robot's playing capabilities have reached the level of an intermediate human instrument player. To make the robot able to play at this performance level, careful calibration of its musical parameters is necessary. Using the flutist robot's core control software, this procedure is very complicated to perform. In this paper we present the implementation of a visual control interface that allows also non-technical users to calibrate the sound settings. The newly developed control interface enables a musician to adjust certain parameters of the robot performance while the robot is playing. Experiments in which we verify the functionality of this sound calibration system are presented. We examine the visual processing system's perception of the instrument movements of a human performer and analyze their effect on the performance of the robot.

In this paper, we present our research on the development of an automated medical ultrasound scanning system for the carotid artery using probe a supporting manipulator (parallel link mechanism). In particular, we detail the mechanism design of the manipulator and a real-time image processing algorithms to detect the carotid artery and tissue layer of its walls (in the B-mode of ultrasound image). Several sequential patterns of ultra-sound probe trajectory were implemented in order to enable the manipulator to scan the surface of neck effectively. A set of experiments has been carried out to verify the effectiveness of the proposed system.

To increase the maximum payload, the joint arrangement of the Stewart platform type leg mechanism for a biped walking vehicle is optimized by a dynamic simulation and a real-coded genetic algorithm. Using effective joint arrangement, the maximum HMS (root-mean-square) value of the current will be able to be reduced. A new prototype of a biped walking vehicle, WL-16RIV, was developed by using the optimal joint arrangement method. Weight saving in some parts was also conducted. Through walking experiments, the maximum R,MS value of the current, was reduced, and the maximum payload was increased. The effectiveness of the proposed method was confirmed

The research on the Waseda Flutist Robot, since 1990, is an approach to understand human motor control from an engineering point of view, as well as introducing novel ways of musical teaching. More recently, the authors have proposed as a long-term goal the aim to enable musical performance robots to interact with musical partners. For this purpose, we present two research approaches: implementing more advanced cognitive capabilities on the Waseda Flutist Robot no. 4 Refined IV (WF-4RIV) (i.e., visual/aural processing) and developing a new musical performance robot (i.e., duet performance). In this paper, we have focused our research on developing an anthropomorphic saxophonist robot as a benchmark to better understand how the interaction with musical partners can be facilitated. As a result, we have developed the Waseda Saxophonist Robot no. 1 (WAS-1) with 15 d.o.f. that mechanically simulates the organs involved during saxophone playing. In this paper, we present the details of the mechanical design of the simulated organs, as well as the implementation of the musical performance control system based on air pressure feedback control. A set of experiments was proposed to verify the effectiveness of the designed simulated organs to produce the saxophone sound and to verify the effectiveness of the proposed air pressure feedback control by comparing the saxophone performance of WAS-1 against an intermediate saxophonist. Finally, a preliminary experiment was carried out to analyze the feasibility of realizing a duet performance with the WF-4RIV. From the experimental results, we have confirmed that WAS-1 is capable of producing a saxophone sound nearly similar in terms of pitch and volume to the performance of a human player. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2010

Purpose: Oral disorders such as temporomandibular joint disorders (TMD) and dry mouth are common and often require treatment. Maxillofacial massage is used as a complementary and alternative therapy for these disorders. We developed an oral rehabilitation robot that massages the maxillofacial tissues for this purpose. In this paper, we propose a control system for oral rehabilitation robots. Method: The control system consists of a massage path generator, virtual compliance calculator, and inverse kinematics calculator. The massage path generator computes a target massage path based on a human head model obtained from a reference MRI image of an adult male. The head model includes the shape and elastic modulus of each component, all of which were obtained experimentally. Virtual compliance control is used to control manipulators with position servo actuators. The manipulators, which have a force sensor at their end-effectors, move actively in the direction of the external force applied to their sensors via virtual compliance control. We implemented this control in WAO-1, our first prototype oral rehabilitation robot. Results: WAO-1 provided massage to three adult male subjects with and without virtual compliance control. One of the subjects was the adult male whose MRI image was used to synthesize the head model in the massage path generator. Without virtual compliance control, the actual massage force was greater than the target massage force, while that with virtual compliance control was less than the target massage force. Furthermore, with virtual compliance control, the massage paths conformed to the head shape of each patient. Conclusion: Implementation of virtual compliance control in the WAO-1 massage robot is feasible and useful for implementation of safe and potentially effective maxillofacial massage therapy. © 2009 CARS.

This paper describes a disturbance avoidance control from environments for a biped walking vehicle. To distinguish between external forces from passenger and those from environments, we use the data of a force sensor mounted on foot to generate an avoidance behavior. To guarantee a walking stability against external forces. a compensation motion around a reference ZMP is generated. Then, external forces are estimated from ZMP errors. By implementing the developed method on the human-carrying biped robot, the robot realized a stable walk under unknown external forces from environments.

Problem statement: Jaw movement analysis, as a clinical aid, can provide an objective basis for understanding and diagnosing jaw musculoskeletal disorders. Therefore, the use and development of devices for quantitatively measuring and analyzing jaw movement have become more common and popular in the clinic. Many types of jaw tracking devices have been developed, but most of them are still not handy and easy to be used. Approach: To improve the handiness and utility of the jaw movement analysis devices, we developed a simple to be used jaw tracking prototype by using a new ultra-miniaturized Inertial Measurement Unit (IMU) named WB-3. The WB-3 IMU was composed by 3-axis gyroscope, 3-axis accelerometer and 3-aixs magnetometer, which can not only measure the acceleration and angular speed of jaw movement, but also can measure mouth opening angle. The IMU's extremely reduced weight and size allowed it to be easily adhered to mandible during normal tests without physical restriction to the subjects. A preliminary experiment for jaw movement analysis during free chewing of three types of food with different shapes and hardness was evaluated. A group of 15 healthy subjects aged from 21-36 years old kindly participated in the experiment. Results: The parameters of chewing time, chewing frequency, power spectrum density of jaw's angular speed and acceleration, cumulative distribution function of jaw's acceleration and mouth opening angle were presented. The experimental results clearly showed that the subjects used less chewing time, less chewing frequency, less acceleration cumulative distribution and energy to eat soft food
higher values were found in the case of hard food and there was no significant difference in mouth opening angle while eating these three foods. Conclusion: Our jaw movement analysis prototype using IMU WB-3 was proved to be a valid and handy method for jaw movement and pattern analysis which may be used clinically as an assistant system for dental therapy. © 2010 Science Publications.

This paper describes about an online pattern generation based on FFT (Fast Fourier Transform). Until now, authors have adopted the offline FFT-based pattern generation. However, it's needed to regard the compensated moment from starting walking to stopping as a periodic function and it's difficult to generate a part of walking pattern. As a solution, it's found that the compensatory waist trajectory for the compensated moment which is cut out with a window of predetermined duration is proper only in the center part of the window. That means the whole trajectory is obtained as a series of the partial ones. Therefore, the online pattern generation is realized by generating a partial trajectories in the proposed way while walking.

This study investigates the effects of semi-passive dynamics bipedal walking on humanoid robots using a simulation approach. WABIAN-2R is a human size robot developed to be used as human motion simulator. It has 39 degrees of freedom of rigid joints and is selected for this study. The actuator of the ankle joint and its harmonic drive is replaced with an elastic joint. This configuration creates a semi-passive bipedal walker, since the rest of the joints are actively controlled to track a desired gait pattern. The passive movement of the elastic ankle joint stores part of the energy of the robot during the collision phase into an elastic form and returns that energy during the rebound phase. The robot can successfully finish a limited number of walking steps.

We have developed a biped humanoid robot, WABIAN-2R as a human motion simulator. However, it was difficult to walk stably on terrain with unevenness of several millimeters. So, we propose an attitude compensation control and a landing pattern modification control (LPMC) to deal with uneven terrain. The LPMC modifies the motion of the landing foot according to the ground surface while the attitude control compensates posture angles of the body based on the 3-axis gyro sensor's data. By integrating two controls, WABIAN-2R is able to walk on outdoor terrain with 5 degree inclination slope and height variations of several millimeters.

Purpose: Oral disorders such as temporomandibular joint disorders (TMD) and dry mouth are common and often require treatment. Maxillofacial massage is used as a complementary and alternative therapy for these disorders. We developed an oral rehabilitation robot that massages the maxillofacial tissues for this purpose. In this paper, we propose a control system for oral rehabilitation robots. Method: The control system consists of a massage path generator, virtual compliance calculator, and inverse kinematics calculator. The massage path generator computes a target massage path based on a human head model obtained from a reference MRI image of an adult male. The head model includes the shape and elastic modulus of each component, all of which were obtained experimentally. Virtual compliance control is used to control manipulators with position servo actuators. The manipulators, which have a force sensor at their end-effectors, move actively in the direction of the external force applied to their sensors via virtual compliance control. We implemented this control in WAO-1, our first prototype oral rehabilitation robot. Results: WAO-1 provided massage to three adult male subjects with and without virtual compliance control. One of the subjects was the adult male whose MRI image was used to synthesize the head model in the massage path generator. Without virtual compliance control, the actual massage force was greater than the target massage force, while that with virtual compliance control was less than the target massage force. Furthermore, with virtual compliance control, the massage paths conformed to the head shape of each patient. Conclusion: Implementation of virtual compliance control in the WAO-1 massage robot is feasible and useful for implementation of safe and potentially effective maxillofacial massage therapy. © 2009 CARS.

The research on the Waseda Flutist Robot, since 1990, is an approach to understand human motor control from an engineering point of view, as well as introducing novel ways of musical teaching. More recently, the authors have proposed as a long-term goal the aim to enable musical performance robots to interact with musical partners. For this purpose, we present two research approaches: implementing more advanced cognitive capabilities on the Waseda Flutist Robot no. 4 Refined IV (WF-4RIV) (i.e., visual/aural processing) and developing a new musical performance robot (i.e., duet performance). In this paper, we have focused our research on developing an anthropomorphic saxophonist robot as a benchmark to better understand how the interaction with musical partners can be facilitated. As a result, we have developed the Waseda Saxophonist Robot no. 1 (WAS-1) with 15 d.o.f. that mechanically simulates the organs involved during saxophone playing. In this paper, we present the details of the mechanical design of the simulated organs, as well as the implementation of the musical performance control system based on air pressure feedback control. A set of experiments was proposed to verify the effectiveness of the designed simulated organs to produce the saxophone sound and to verify the effectiveness of the proposed air pressure feedback control by comparing the saxophone performance of WAS-1 against an intermediate saxophonist. Finally, a preliminary experiment was carried out to analyze the feasibility of realizing a duet performance with the WF-4RIV. From the experimental results, we have confirmed that WAS-1 is capable of producing a saxophone sound nearly similar in terms of pitch and volume to the performance of a human player. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2010

Robot Technology should contribute to the progress of other research fields. We'd like to propose one example of it. In psychology, basic medicine and biological science, several experiments on animal behavior have been performed to clarify brain functions or mechanisms of learning. These experiments have been playing very important role to understand human mind. Rats and mice have been well used in these experiments. Therefore, we have been developing quadruped robots that reproduce animal behavior as new experimental tools. We developed a quadruped robot that has 4 legs and reproduces some social behaviors. Each leg has 3 DOFs. The robot also has 2 DOF at the neck and 2 DOF at the waist.

Purpose Fibre optic colonoscopy is usually performed with manual introduction and advancement of the endoscope, but there is potential for a robot capable of locomoting autonomously from the rectum to the caecum. A prototype robot was designed and tested. Methods The robot colonic endoscope consists in a front body with clockwise helical fin and a rear body with anticlockwise one, both connected via a DC motor. Input voltage is adjusted automatically by the robot, through the use of reinforcement learning, determining speed and direction (forward or backward). Results Experiments were performed both in-vitro and in-vivo, showing the feasibility of the robot. The device is capable of moving in a slippery environment, and reinforcement learning algorithms such as Q-learning and SARSA can obtain better results than simply applying full tension to the robot. Conclusions This self-propelled robotic endoscope has potential as an alternative to current fibre optic colonoscopy examination methods, especially with the addition of new sensors under development. © CARS 2010.

This paper reports on the development of an Airway Management Training System. Airway management is a standard operation executed in emergency and operating rooms. However, medical accidents occur due to unskilled operations. In order to avoid accidents, medical doctors undergo to mannequin-based training. However, traditional training techniques do not provide quantitative information on the trainees performance and are not capable to assess the trainees performance based on the quantitative information. In this context, we proposed a novel airway management training system, dubbed WKA-3. This work presents both the electromechanical and the control sub-systems of the WKA-3. The results of preliminary experiments carried out by medical doctors to doctors to verify the training system are also provided.

Our research is related to the development of an anthropomorphic saxophonist robot, which it has been designed to mechanically reproduce the organs involved during the saxophone playing. Our research aims in understanding the motor control from an engineering point of view and enabling the communication between humans and robots in musical terms. In this paper, we present the Waseda Saxophone Robot No. 2 (WAS-2) which is composed by 22-DOPs. In particular, the lip mechanism of WAS-2 has been designed with 3-DOFs to control the motion of the lower, upper and sideways lips to increase the sound range and to reproduce the dynamic effect of the sound (i.e. crescendo and decrescendo). In addition, a human-like hand (16-DOFs) has been designed to enable to play all the keys of the instrument. A set of experiments were carried out to verify the effectiveness of the mechanical design and the control system improvements.

Personal robots and Robot Technology (RT)-based assistive devices are expected to play a substantial role in our society, largely populated by elders; they will play an active role in joint works and community life with humans. In particular, these robots are expected to play an important role for the assistance of elderly and disabled people during normal activities of daily living (ADLs). To achieve this result, personal robots should be also capable of human-like emotion expressions. In this perspective we developed a whole body bipedal humanoid robot, named KOBIAN, which is also capable to express human-like emotions. In this paper we present the mechanical and modular design of KOBAIN.

This paper describes an avoidance behavior from unknown external forces for a biped walking vehicle. To distinguish between external forces from passenger and those from environments, we use the data of a force sensor mounted on foot, and external forces are estimated from ZMP errors. To guarantee a walking stability, the waist position is adjusted to match the measured ZMP to the reference ZMP, and the position of landing foot is adjusted so that the waist trajectory does not diverge. By implementing the developed method on the human-carrying biped robot, the robot realized a stable walk under unknown external forces from environments. When pushing the robot stepping, the robot moved backward and moved away from the generation source of external forces about 400 mm. When pushing the robot walking forward, the robot stopped going forward and prevented from coming closer to the generation source of external forces. We confirmed the effectiveness of the proposed control through these experiments.

We have developed a new biped foot mechanism capable of detecting ground surface to realize stable walking on uneven terrain. The size of the foot mechanism is 160 mm x 277 mm and its weight is 1.5 kg. The foot system consists of four spikes each of which has an optical sensor to detect ground height. The foot makes a support polygon on uneven terrain by using three or four spikes. We have conducted several experiments on the outdoor ground surface that has a slope of 7.0 degrees and a maximum height of 15 mm bumps, and the effectiveness of the foot mechanism is confirmed.

Purpose Fibre optic colonoscopy is usually performed with manual introduction and advancement of the endoscope, but there is potential for a robot capable of locomoting autonomously from the rectum to the caecum. A prototype robot was designed and tested. Methods The robot colonic endoscope consists in a front body with clockwise helical fin and a rear body with anticlockwise one, both connected via a DC motor. Input voltage is adjusted automatically by the robot, through the use of reinforcement learning, determining speed and direction (forward or backward). Results Experiments were performed both in-vitro and in-vivo, showing the feasibility of the robot. The device is capable of moving in a slippery environment, and reinforcement learning algorithms such as Q-learning and SARSA can obtain better results than simply applying full tension to the robot. Conclusions This self-propelled robotic endoscope has potential as an alternative to current fibre optic colonoscopy examination methods, especially with the addition of new sensors under development. © CARS 2010.

The research on the Waseda Flutist Robot, since 1990, is an approach to understand human motor control from an engineering point of view, as well as introducing novel ways of musical teaching. More recently, the authors have proposed as a long-term goal the aim to enable musical performance robots to interact with musical partners. For this purpose, we present two research approaches: implementing more advanced cognitive capabilities on the Waseda Flutist Robot no. 4 Refined IV (WF-4RIV) (i.e., visual/aural processing) and developing a new musical performance robot (i.e., duet performance). In this paper, we have focused our research on developing an anthropomorphic saxophonist robot as a benchmark to better understand how the interaction with musical partners can be facilitated. As a result, we have developed the Waseda Saxophonist Robot no. 1 (WAS-1) with 15 d.o.f. that mechanically simulates the organs involved during saxophone playing. In this paper, we present the details of the mechanical design of the simulated organs, as well as the implementation of the musical performance control system based on air pressure feedback control. A set of experiments was proposed to verify the effectiveness of the designed simulated organs to produce the saxophone sound and to verify the effectiveness of the proposed air pressure feedback control by comparing the saxophone performance of WAS-1 against an intermediate saxophonist. Finally, a preliminary experiment was carried out to analyze the feasibility of realizing a duet performance with the WF-4RIV. From the experimental results, we have confirmed that WAS-1 is capable of producing a saxophone sound nearly similar in terms of pitch and volume to the performance of a human player. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2010

Problem statement: Jaw movement analysis, as a clinical aid, can provide an objective basis for understanding and diagnosing jaw musculoskeletal disorders. Therefore, the use and development of devices for quantitatively measuring and analyzing jaw movement have become more common and popular in the clinic. Many types of jaw tracking devices have been developed, but most of them are still not handy and easy to be used. Approach: To improve the handiness and utility of the jaw movement analysis devices, we developed a simple to be used jaw tracking prototype by using a new ultra-miniaturized Inertial Measurement Unit (IMU) named WB-3. The WB-3 IMU was composed by 3-axis gyroscope, 3-axis accelerometer and 3-aixs magnetometer, which can not only measure the acceleration and angular speed of jaw movement, but also can measure mouth opening angle. The IMU's extremely reduced weight and size allowed it to be easily adhered to mandible during normal tests without physical restriction to the subjects. A preliminary experiment for jaw movement analysis during free chewing of three types of food with different shapes and hardness was evaluated. A group of 15 healthy subjects aged from 21-36 years old kindly participated in the experiment. Results: The parameters of chewing time, chewing frequency, power spectrum density of jaw's angular speed and acceleration, cumulative distribution function of jaw's acceleration and mouth opening angle were presented. The experimental results clearly showed that the subjects used less chewing time, less chewing frequency, less acceleration cumulative distribution and energy to eat soft food
higher values were found in the case of hard food and there was no significant difference in mouth opening angle while eating these three foods. Conclusion: Our jaw movement analysis prototype using IMU WB-3 was proved to be a valid and handy method for jaw movement and pattern analysis which may be used clinically as an assistant system for dental therapy. © 2010 Science Publications.

Recently, in medical field, different training methods for medical staff have been proposed. However, the lack of knowledge on the real improvements of trainees makes difficult the real effectiveness of those proposed methods. Therefore, we are proposing an Active Training system for the effective medical training. The Active training system is characterized by providing quantitative information of the trainee's performance of the task to the trainee, simulating real-world conditions of the task, and assuring training effectiveness. In order to fulfill each of these characteristics, we have developed Waseda Kyotokagaku Airway No. 3 (WKA-3) which makes it possible to obtain quantitative information for the trainee's performance and reproduce the various cases, individual differences for the airway difficulties for the simulating real-world conditions of the task. In this paper, we are proposing a patient scenario generation which can reproduce the characteristics of the patient simulating real-world conditions of the task for WKA-3. In emergent situation or surgical operation, the characteristics of patients are presented in the three parameters such as: patient initial conditions, time variant status change, and reflex action. By adjusting, and combining each of the three parameters, we can reproduce the various patient scenarios. In this paper, we also state how to generate the Patient Scenario Generation using the position control and virtual compliance control. Finally, a set of experiments has been carried out to the doctor subjects in order to verify effectiveness of the proposed Patient Scenario Generation, and discuss the doctors about the result of the experiments.

An active training system is characterized by providing quantitative information of the trainee's performance of the task to the trainee, simulating real-world conditions of the task, and assuring training effectiveness. For this purpose, the authors have been developing an Airway management training system. In particular, we have previously presented an evaluation model system to acquire quantitative information for the trainee's performance, and an actuated model system for real-world conditions of the task. In order to fulfill all of the characteristics of the active training system; in this paper, we would like to propose an integrated system, Waseda Kyotokagaku Airway No. 3 (WKA-3) which integrates the function of both system models. For this reason, we have focused on embedding sensors and actuators with the link drive mechanism and the wire drive mechanism to a conventional patient model towards the development of a patient robot. In this paper, we present WKA-3 how to design the mechanism and how to redesign several organs to embed the sensors for the measurement of the trainee's performance. A set of experiment have been carried out to doctor subjects using the WKA-3 to verify the effectiveness of the proposed system by asking doctors to evaluate the proposed system.

The number of patients with mental disorders is increasing in advanced countries. Many researchers are working to develop mental disorder model animals that contribute to development of new psychotropic drugs. However, we have some doubts about conventional mental disorder models. Therefore, the purpose of this study is to develop an experimental setup to create novel mental disorder model animals. We then developed a small mobile robot and a control system for the robot. Using them, we performed an experiment to develop a mental disorder model rat. In the experiment, we succeeded in developing a new depression model rat and also high activity model rat. These disorder models must be useful in the screening of new psychotropic drugs. In addition, the methodology we developed in this research will contribute to clarifying mechanisms of mental disorders.

In the domain of psychology and medical science, many experiments have been conducted referring to research on animal behaviors, to study the mechanism of mental disorders and to develop psychotropic drugs to treat them. Rodents such as rats are often chosen as experimental subjects in these experiments. However, according to some researchers, the experiments on social interactions using animals are poorly-reproducible. Therefore, we consider that the reproducibility of these experiments can be improved by using a robotic agent that interacts with an animal subject. We have developed a novel quadruped rat-inspired robot, the WR-2 (Waseda Rat No. 2), based on the dimension and body structure of a mature rat. It is capable of reproducing the behaviors such as walking, mounting, rearing and grooming of the rat.

This paper presents the design and development of a bio-inspired mobile robot called WR-3 (Waseda Rat No. 3), as an experimental tool to study social interaction between rats and robots. According to the motion analysis of rats, their motion can be divided into two phases: moving and interaction. Therefore, a novel hybrid mechanism in which wheels are used for moving and legs are used for interaction has been designed to actuate the WR-3. Consequently, the robot can move at a high speed using its wheels and reproduce the rats' interaction using its legs and other parts. Based on the dimension and body structure of a mature rat, WR-3 has been designed with dimensions of 240x70x90[mm] and is the same shape as a rat. It consists of 18 DOFs in total: two 1-DOF wheels, four 3-DOF legs (including passive DOFs), a 2-DOF waist, and a 2-DOF neck. Preliminary interaction experiments with rats demonstrate that WR-3 is capable of reproducing interactions such as following, rearing, grooming, mounting, etc. similar to a real rat.

Robot Technology should contribute to the progress of other research fields. We'd like to propose one example of it. In psychology, basic medicine and biological science, several experiments on animal behavior have been performed to clarify brain functions or mechanisms of learning. These experiments have been playing very important role to understand human mind. Rats and mice have been well used in these experiments. Therefore, we have been developing quadruped robots that reproduce animal behavior as new experimental tools. We developed a quadruped robot that has 4 legs and reproduces some social behaviors. Each leg has 3 DOFs. The robot also has 2 DOF at the neck and 2 DOF at the waist.

This paper presents the comparison of the WB-3 ultra-miniaturized inertial measurement unit (EMU), developed by our group, with the commercial EMU IntertiaCube by InterSense and the Vicon motion capture system. WB-3 is provided with a 32-bit microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer). We implemented an Extended Kalman Filter (EKF) based on quaternion for the sensor fusion to retrieve the attitude. A new methodology for the automatic estimation of the measurement covariance matrix on the EKF is presented (R-Adaptive Algorithm). The preliminary results showed that WB-3 performance is comparable with Vicon. The R-Adaptive Algorithm improves the attitude reconstruction in case of non-static condition compared with the commercial IMU. © 2010 IEEE.

Performing laparoscopic surgery requires several skills which have never been required for conventional open surgery, surgeons experience difficulties in learning and mastering these techniques. Various training methods and metrics have been developed in order to assess and improve surgeon's operative abilities. While these training metrics are currently widely being used, skill evaluation methods are still far from being objective in the regular laparoscopic skill education. This study proposes a methodology of defining a processing model to objectively evaluate surgical performance and skill expertise in the routine laparoscopic training course. Our approach is based on the analysis of kinematic data describing the movements of surgeon's upper limbs. An ultra-miniaturized wearable motion capture system (Waseda Bioinstrumentation system WB-3), therefore, has been developed to measure and analyze these movements. The skill evaluation model was trained by using the subjects' motion features acquired from WB-3 system and further validated to classify the expertise levels of the subjects with different laparoscopic experience. Experimental results show that, the proposed methodology can be efficiently used both for quantitative assessment of surgical performance, and for the discrimination between expert surgeons and novices. © 2010 IEEE.

Mastication analysis can provide an objective basis for studying and diagnosing jaw musculoskeletal disorders. Therefore, the use and development of devices for quantitatively measuring and analyzing jaw movement have become very popular in the consulting room. This paper proposes a simple to be used jaw tracking prototype by using the new miniaturized wireless Inertial Measurement Unit (IMU) named WB-4. The WB-4 IMU primarily contains a mother board, a Bluetooth module and a Li-Polymer battery. The mother board is provided with a microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure the jaw motion. The data transmission between WB-4 and PC is based on the Bluetooth module to realize the wireless communication. The IMU's extremely reduced weight and size allows it to be easily attached to mandible during normal mastication tests without physical restriction to the subjects. Three pilot experiments for mastication analysis of chewing gum were elaborated. A group of 9 healthy subjects kindly participated in the experiment. The preliminary results show that WB-4 IMU can efficiently evaluate the jaw movement and mastication pattern of different subjects, which could provide quantitative information to the doctors for the diagnosing and clinical treatment of different jaw diseases. ©2010 IEEE.

Real-time tracking of human body motion is an important technology in synthetic environments, robotics, and other human-computer interaction applications. This paper presents an ultra-miniaturized inertial measurement unit (IMU) named WB-3 for real-time attitude estimation of human limb segments. The WB-3 IMU is provided with a 32-bit microcontroller and 9-axis inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer). The quaternion-based Extended Kalman Filter (EKF) was implemented for the sensor fusion to retrieve the attitude of the human segment. An upper body motion capture system with 12 WB-3 IMUs was elaborated for tracking human movements in real time scenarios. ©2010 IEEE.

Personal robots anticipated to become popular in the future are required to be active in joint work and community life with humans. These personal robots must recognize changing environment and must conduct adequate actions like human. Visual tracking can be said as a fundamental function from the view point of environmental sensing and reflex reaction against it. The authors developed a visual tracking motion algorithm by using upper body. Then, we integrated it with an online walking pattern generator and developed a visual tracking biped locomotion. Finally, we conducted an experimental evaluation with emotion expression.

The research on Music Playing-Instrument Humanoid Robots (MP-HRs) has a long tradition in the research field of robotics since the development of the humanoid pianist robot WABOT-2 developed at Waseda University (1984). Since then, several researchers have been aiming for the better understanding of the human musical performance. For this purpose, different mechanical designs and cognitive functions have been implemented on them. A particular interest was given to wind instruments as a research approach for understanding human breathing mechanism. Nowadays, different kinds of automated machines and humanoid robots have been developed for playing wind instruments to understand the human motor control from an engineering point of view. Moreover, the importance of studying the ways of enabling the interaction between musicians-humanoid is being attracting several researchers from different research fields. As a long-term research goal, we are aiming to enable wind playing-instrument humanoid robots to display motor dexterities and high-level perceptual capabilities to interact with other musician partners. In this paper, we present our current research achievements on the development of an anthropomorphic saxophonist robot and the implementation of a musical-based interaction system tested on an anthropomorphic flutist robot.

Our research aims in developing an anthropomorphic saxophonist robot designed to mechanically reproduce the human organs involved during the saxophone playing. In this paper, the (Wa) under bar seda (S) under bar axophone Robot No. (2) under bar (WAS-2) which is composed by 22-DOFs is detailed. The lip mechanism of WAS-2 has been designed with 3-DOFs to control the motion of the lower, upper and sideway lips. In addition, a human-like hand (16 DOF-s) has been designed to enable to play all the keys of the instrument. Regarding the improvement of the control system, a feed-forward control system with dead-time compensation has been implemented to assure the accurate control of the air pressure. In addition, the implementation of an auditory feedback control system has been proposed and implemented in order to adjust the positioning of the physical parameters of the components of the robot by providing a pitch feedback and defining a recovery position (off-line). A set of experiments were carried out to verify the mechanical design improvements and the dynamic response of the air pressure. As a result, the range of sound pressure has been increased and the proposed control system improved the dynamic response of the air pressure control.

The flutist robot WF-4RIV at Waseda University is able to play the flute at the level of an intermediate human player. So far the robot has been able to play in a statically sequenced duet with another musician, individually communicating only by keeping eye-contact. To extend the interactive capabilities of the flutist robot, we have in previous publications described the implementation of a Music-based Interaction System (MbIS). The purpose of this system is to combine information from the robot's visual and aural sensor input signal processing systems to enable musical communication with a partner musician. In this paper we focus on that part of the MbIS that is responsible for mapping the information from the sensor processing system to generate meaningful modulation of the musical output of the robot. We propose a two skill level approach to enable musicians of different ability levels to interact with the robot. When interacting with the flutist robot the device's physical capabilities / limitations need to be taken into account. In the beginner level interaction system the user's input to the robot is filtered in order to adjust it to the state of the robot's breathing system. The advanced level stage uses both the aural and visual sensor processing information. In a teaching phase the musician teaches the robot a tone sequence (by actually performing the sequence) that he relates to a certain instrument movement. In a performance phase, the musician can trigger these taught sequences by performing the according movements. Experiments to validate the functionality of the MbIS approach have been performed and the results are presented in this paper.

Humanoid robots are developed to be used in many areas in the human environment, especially area where it is highly dangerous for human to work or live in. Outer space or even the moon surface is one of the areas where are people trying to explore, but it is highly risky and costly. Sending humanoid robot to the moon could one of the solution to explore the moon surface and research on the real effect of the moon gravity on human walking motion. Using dynamic simulation we can have an approach to imitate human walking gait and analyze the effect of the low gravity which could result on the walking velocity.

Humanoid robots are becoming an important factor for the future work. The researches in this field are focusing on the ability of using Humanoid robots in many areas where human live and work. Future planes are made to explore the surface of the moon for different purposes which requires long present and existing by human. The development of humanoid robot to work in such environment for the purpose of human assisting is becoming highly demanded. The challenge of developing a bipedal robot to walking on the moon is really high due the low gravity compare to earth. The effect of the low gravity may result in unstable walking which will require lower walking velocity. In order to have higher velocity it is better to switch to running gait instead of walking gait. In the paper we investigate the ability to perform a jumping motion on the moon gravity as a first step toward developing a running gait motion. © 2010 IEEE.

The main goal of this paper is to report a successful attempt of monitoring the stiffness behavior of a biped walking vehicle during its dynamic operation. In particular, a suitable procedure has been developed and implemented for estimating the stiffness performance of WL-16RV as based on previous experiences at LARM with Milli-CaTraSys design. The proposed experimental set-up is composed of six linear encoder wire sensors and two force/torque sensors embedded in each foot. Experimental tests are conducted on a biped walking vehicle WL-16RV under static and dynamic conditions. The experimental tests provide useful information for both design and control purposes.

In this paper, we present a robotic system which automatically searches and detects the longitudinal section of the carotid artery using a conventional medical ultrasound diagnostic system. In order to obtain a clear image of the carotid artery ready for medical diagnosis, the authors developed real-time image processing algorithms to detect the carotid artery and tissue layers of its walls in the B-mode ultrasound images. Sequential patterns of the ultrasound probe trajectory for scanning the surface of the neck and searching the carotid, were implemented and tested on the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement Robot System No. 1 Refined II (WTA-1RII). An experiment with eleven volunteers was carried out and the results show that the system obtained clear images of the carotid artery in 91% of the trials.

We have developed a mechanical talking robot, Waseda Talker No. 7 Refined II, to study the human speech mechanism. The conventional control method for this robot is based on a concatenation rule of the phoneme-specific articulatory configurations. With this method, the speech mechanism of the robot is much slower than is required for human speech, because the robot requires momentary movement of motors. To resolve this problem, we have developed a control method that mimics human articulatory trajectory data. The human trajectory data for continuous speech was obtained by using an electromagnetic articulography (EMA) system. The EMA data was converted to the robot control parameters by applying inverse kinematics as well as geometric transformation. Experimental results show that the robot can produce continuous speech with human-like speed and smooth movement.

Heart and cerebrovascular diseases such as arteriosclerosis and myocardial ischemia dysfunction are currently among the main causes of death in developed countries. Recently, wave intensity (WI), which is an index used to obtain the force of cardiac contraction, has been investigated as a method for early-stage diagnosis of the above-mentioned diseases. Nevertheless, experimental tests have proven that the manual measurements of WI by means of commercial ultrasonic diagnostic systems require too much time and can be affected by the operator&apos;s skills. For this purpose, the introduction of robotic-assisted technology has advantages in terms of repetitiveness and accuracy of the measurement procedure. Therefore, at Waseda University, the development of a carotid blood flow measurement system has been proposed to support doctors while using ultrasound diagnostic equipment to measure the WI. This robotic system is composed of a serial robot with a wrist having a six-degree-of-freedom (6-DOF) parallel mechanism. The main focus is to obtain a suitable workspace performance of the 6-DOF parallel mechanism wrist. In this paper, a workspace analysis is carried out on a wrist prototype built for the Waseda-Tokyo Women&apos;s Medical Aloka Blood Flow Measurement System No. 1 Refined (WTA-1R). Then, mechanical design enhancements are proposed and validated to provide a suitable workspace performance both as reachable workspace and dexterity, and a refined prototype WTA-1RII has been built.

We have developed an oral-rehabilitation robot WAO-1 (Waseda Asahi Oral-rehabilitation robot No. 1) for use in cases of oral disorders such as temperomandibular joint (TMJ) disorder and dry mouth. WAO-1 is the first robot designed to provide massage to the facial tissues of a patient with oral disorders. This robot provides massage to the masseter and temporal muscles and to the parotid gland and duct with simple operation. It consists of two six-degree-of-freedom arms with plungers, a body with headrest, a control box, a PC, and an automatic massage trajectory generation system with virtual compliance control. Two evaluation experiments were performed to verify the effectiveness of the oral massages of WAO-1 compared with the massages given by doctors. In the experiments, the massage to the parotid gland and duct by WAO-1 increased the amount of saliva in the subjects, and the massage to the masseter muscle by WAO-1 increased facial skin temperature and width of the masseter muscle in the subjects. We consider that these results indicate that massage by WAO-1 can be effective for patients with oral disorders.

We developed an oral-rehabilitation robot WAO-1 for use in cases of oral disorders such as TMJ (Temporomandibular Joint) disorder and dry mouth. WAO-1 is the first robot designed to provide massage to the facial tissues of a patient with oral disorders. This robot provides massage to the masseter and temporal muscles and to the parotid gland and duct with simple operation. It consists of two 6-DOF arms with plungers, a body with head rest, a control box, a PC, and an automatic massage trajectory control system with virtual compliance control. The massage trajectories are generated using the face shape model of an adult male before the massage. During the massage, compliance displacement xcc is calculated based on the reaction force from the face in real time. Using the virtual compliance control, it is possible to apply the massage trajectories made from the facial shape model of an adult male to many people without modification of the model.

Objectives: This study determined suitable conditions for masseter and temporal muscle massage using a specially fabricated robot and evaluated its effects on patients with TMJ dysfunction associated with myofascial pain. Methods: The robot was designed with two arms with six degrees-of-freedom, and equipped with plungers. A phase-1 trial examined 22 healthy volunteers to determine its safety and suitable massage pressure, examining three different pressures. The volunteers evaluated their comfort, warmth, and ease of mouth opening by use of a visual analogue scale (VAS). A phase-2 trial examined the safety, suitable dose regimen, and efficacy in 12 patients. Maximal mouth opening was measured, and muscle pain and massage were evaluated subjectively. Results: The robot was safe in the phase-1 trial, except for two massages in which the pressure was excessive. Massages at 6-10 N were given the highest VAS scores. In phase 2, the massage pressure was arbitrary and each muscle was massaged seven times for 1 min, three times every two weeks. After evaluating the efficacy, additional treatments were performed at a greater pressure or for longer. The massage treatment was very effective for most patients. Conclusion: The massage treatment was safe and effective for most patients when administered at a pressure of 6-10 N seven times for 1 min per muscle every two weeks. The robot may constitute a useful tool for treating TMJ dysfunction associated with myofascial pain. © 2009 Japanese Society for Oral and Maxillofacial Radiology and Springer.

Up to now, different kinds of musical performance robots (MPRs) and robotic musicians (RMs) have been developed. MPRs are designed to closely reproduce the required motor skills displayed by humans (i.e. anthropomorphic robots) in order to play musical instruments. MPRs are then usually conceived as benchmarks to study the human motor control from an engineering point of view and to better understand the human-robot interaction from a musical stand point. In contrast, RMs are conceived as automated mechanisms designed for the creation of new ways of musical expression from the musical engineering perspective. Our research on the anthropomorphic flutist robot, at Waseda University, has been focused on clarifying the human motor control while playing the flute, proposing novel applications for humanoid robots and enabling the communication with humans at the emotional level of perception. In this paper, we are presenting the details of the development of the Waseda flutist robot No. 4 Refined IV (WF-4RIV). The WF-4RIV is composed by 41-DOFs that reproduce the anatomy and physiology of the organs involved during the flute playing. In particular, we describe the new mechanical design of the artifical organs; such as lips, tonguing, vibrato and lungs, which are related to the production of a clear sound. A set of experiments were proposed to verify the effectiveness of each of the mechanisms to imitate the human flute playing. From the experimental results, the WF-4RIV is able of producing clear sound with smoother transitions between notes. (c) 2008 Elsevier Ltd. All rights reserved.

Personal robots and robot technology (RT)-based assistive devices are expected to play a major role in our elderly-dominated society, with an active participation to joint works and community life with humans, as partner and as friends for us. In particular, these robots are expected to be fundamental for helping and assisting elderly and disabled people during their activities of daily living (ADLs). To achieve this result, personal robots should be also capable of human-like emotion expressions. To this purpose we developed a new whole body emotion expressing bipedal humanoid robot, named KOBIAN, which is also capable to express human-like emotions. In this paper we presented three different evaluations of the emotional expressiveness of KOBIAN. In particular In particular, we presented the analysis of the roles of the face, the body, and their combination in emotional expressions. We also compared Emotional patterns created by a Photographer and a Cartoonist with the ones created by us. Overall, although the experimental results are not as good as we were expecting, we confirmed the robot can clearly express its emotions, and that very high recognition ratios are possible. © 2009 IEEE.

The research on human-robot interaction (HRI) has been an emerging topic of interest for both basic research and customer application. The studies specially focus on behavioral and cognitive aspects of the interaction and the social contexts surrounding it. HRI issues have long been a part of robotics research because the goal of fully autonomous capability has not been met yet. One of the most challenging problems is giving the robots an understanding of how to interact with human beings at the same logical level so that they may function not as passive tools, but rather as active agents that can drive the human interaction, instead of merely reproducing a sequence of movements. Hence, these robots must have higher level cognitive functions that include knowing how to reason, when to perceive and what to look for, how to integrate perception and action under changing conditions, etc. These functions will enable robots to perform more complex tasks which require tight human interaction; consequently, the robots can perform high level interactions such as teaching motor skills to unskilled people. In this paper, the development of active training systems for medical training purposes designed to provide quantitative information as well as to provide feedback to medical students are detailed.

It is well known that the massage therapy is useful for the rehabilitation of various diseases (i.e. oral health problems, etc.). Although various apparatus have been developed for the massage of the torso and limbs, there is still little knowledge about their real effectiveness. For this purpose, authors have proposed the development of a robotic system that provides massage therapy of the maxillofacial region to patients with temporomandibular joint disorders. As a result of our research, we have developed the Waseda-Asahi Oral-Rehabilitation No.1 (WAO-1), which it is composed by two six-degrees of freedom arms with plungers attached at their end-effector. Preclinical tests were carried out to confirm the effectiveness of the proposed system. In order to evaluate the safety measures of the applied forces during the massage therapy, we have based our analysis on the Visual Analogue Scale (VAS) which is a conventional subjective evaluation methods commonly used in the medical field. From the experimental results, we could confirm the effectiveness of the therapy provided by WAO-1.

It is well known that the massage therapy is useful for the rehabilitation of various diseases (i.e. oral health problems, etc.). Although various apparatus have been developed for the massage of the torso and limbs, a machine to perform precise massage therapy to maxillofacial region is not developed yet. The ability of a robotic system to exert itself without fatigue aims in providing more hours of therapy per day, resulting in an increased number of patients that can be treated. This increased potential for treatment would benefit the elderly persons as well allowing more frequent treatments and more convenience in scheduling. For this purpose, the authors have developed the Oral-Rehabilitation Robot which provides massage of the maxillofacial region as a therapy to patients with temporomandibular joint disorders, etc. Then, we developed the Waseda-Asahi Oral-Rehabilitation Robot No.1 Refined (WAO-1R) by redesigning the arms of WAO-1 to increase variety of massage. By this improvement, the angular limitation of end-effector is increased from 60 degrees to 360 degrees. In order to assess the effectives of the massage provided by the robotics system, different performances indexes were proposed based on the medical literature and from our discussion with experts. A set of experiments were carried out to confirm if the mechanical improvements enhanced or not the effect of the massage provided by the WAO-1R. From the experimental results, we could detect increasing the thickness of masseter muscle on volunteers and the amount of mouth-opening after providing the massage with WAO-1R compared with the previous robot.

The emerging field of medical robotics aims to introduce intelligent tools to assist a physician. The main challenges for developing efficient medical robotic training systems are simulating real-world conditions of the task and assuring training effectiveness. High anatomic fidelity has been achieved in current systems. However, those training systems are designed to reproduce specific conditions of the task (passive training). In this research, we are focusing in developing an airway management training systems designed to reproduce various cases of difficult airway. Such difficulties (i.e. restricted mouth opening, various shapes of oral cavity including tongue swallowing, etc) may provoke traumas on different organs of the patient during an emergency situation. For this purpose, the authors have proposed the development of more advanced training tools. For this purpose, we have focused in embedding sensors and actuators to a conventional patient model towards the development of a patient robot (in previous research, authors have presented the evaluation model which embeds sensors). In this paper, we present an airway training system which embeds actuators into a mannequin. In particular, the mechanism design of the Waseda Kyotokagaku Airway No.2 (WKA-2) is detailed. The WKA-2 is composed of twelve active and one passive degrees of freedom; which are designed to reproduce the various cases of difficult airway. For this purpose, the WKA-2 reproduces the human muscles around the upper airway based on a wire driving mechanisms (a total of sixteen wires are used). In particular, the head of the model is composed of a tongue and mandible with translational and rotational movements around kinematic axis. In addition, we present the details of the kinematic model of WKA-2 which enable the robot to reproduce the airway difficulties. Finally, we presented the design of a tension sensor designed to measure the applied tension on each of the wire driving mechanism of WKA-2. As preliminary experiments, we reproduce several cases of difficult airways using WKA-2.

Up to now, different kinds of medical training systems have been developed which were designed to reproduce the human anatomy in high fidelity. However, these kinds of systems are limited to provide quantitative information of the trainees' operation, only provide subjective assessment to them, and finally to provide few feedbacks to them. Therefore, we would like to propose the advanced medical training method using RT which enables us to not only provide quantitative information of the trainees' operation, but also objective evaluation to them from the quantitative information. For the purpose of these facts, we developed Waseda Kyotokagaku Airway-No.1 Refined (WKA-1R) which embeds many sensors in order to provide quantitative information of the trainees' skill as well as an evaluation unit for them. However, the force sensor of WKA-1R has three problems, such as a limited measurement of the applied force, calibration, and maintenance for practicality. In this paper, we propose newly developed Tension/Compression Detection Sensor System (TCDSS) which not only reinforces calibration and maintenance for practicality, but also enables us to measure tension, compression, and torque. In addition, we also propose a Tactile Detection Sensor System (TDSS) which enables us to obtain the information of tactile sensation of the robot. Finally, preliminary experiments have been proposed to obtain the characteristic curve on the TCDSS.

In recent years there has been an ever increasing amount of research and development of technologies and methods to improve the quality and the performance of advanced surgery. In several fields, such as laparoscopy, various training methods and metrics have been proposed, both to improve the surgeon's abilities and also to assess her/his skills. For neurosurgery, however, the extremely small movements and target operating space involved have prevented until now the development of similar methodologies and systems.
In this paper we present the development of an ultra-miniaturized Inertial Measurement Unit (IMU) and its application for neurosurgery skill assessment in a simple pick and place scenario. This analysis is a preliminary yet fundamental step to realize a better training/evaluation system for neurosurgeons, and to objectively evaluate and understand how the neurosurgery is performed.

The bipedal humanoid robot WABIAN-2R is developed to simulate human locomotion. Performing a walking motion requires a high torque at the ankle joint. WABIAN-2R consists of harmonic gears in its driveline system which increases the weight of each leg and respectively decreases the energy economy. Therefore, a new idea is proposed and developed in this paper through computer simulation to modify the design of the ankle joint by adding a spring mechanism instead of high gear ratio transmission. The spring stiffness could be controlled by twisting the joint to set the required torque. This helps reduce the energy consumed while walking; by storing and returning part of the energy. Research presented in this paper proposes an important step toward developing the passive dynamics walking into the advanced complex humanoid robots.

The bipedal humanoid robot WABIAN-2R is developed to simulate human locomotion. Performing a walking motion requires a high torque at the ankle joint. WABIAN-2R consists of harmonic gears in its driveline system which increases the weight of each leg and respectively decreases the energy economy. Therefore, a new idea is proposed and developed in this paper through computer simulation to modify the design of the ankle joint by adding a spring mechanism instead of high gear ratio transmission. This helps reduce the energy consumed while walking; by storing and returning part of the energy. Research presented in this paper proposes an important step toward developing the passive dynamics walking into the advanced complex humanoid robots.

The bipedal humanoid robot WABIAN-2R is developed to simulate human locomotion. Performing a walking motion requires a high torque at the ankle joint. WABIAN-2R consists of harmonic gears in its driveline system which increases the weight of each leg and respectively decreases the energy economy. Therefore, a new idea is proposed and developed in this paper through computer simulation to modify the design of the ankle joint by adding a spring mechanism instead of high gear ratio transmission. The spring stiffness could be controlled by twisting the joint to set the required torque. This helps reduce the energy consumed while walking; by storing and returning part of the energy. Research presented in this paper proposes an important step toward developing the passive dynamics walking into the advanced complex humanoid robots.

The bipedal humanoid robot WABIAN-2R is developed to simulate human locomotion. Performing a walking motion requires a high torque at the ankle joint. WABIAN-2R consists of harmonic gears in its driveline system which increases the weight of each leg and respectively decreases the energy economy. Therefore, a new idea is proposed and developed in this paper through computer simulation to modify the design of the ankle joint by adding a spring mechanism instead of high gear ratio transmission. This helps reduce the energy consumed while walking; by storing and returning part of the energy. Research presented in this paper proposes an important step toward developing the passive dynamics walking into the advanced complex humanoid robots.

In recent years there has been an ever increasing amount of research and development of technologies and methods to improve the quality and the performance of advanced surgery. In other fields several training methods and metrics have been proposed, both to improve the surgeon's abilities and also to assess her/his skills. For neurosurgery, however, the extremely small movements and sizes involved have prevented until now the development of similar methodologies and systems. In this paper we present the development of an ultra-miniaturized Inertial Measurement Unit and its application for the evaluation of the performance in a simple pick and place scenario. This analysis is a preliminary yet fundamental step to realize a better training/evaluation system for neurosurgeons, and to objectively evaluate and understand how the neurosurgery is performed.

This paper investigates mechanical design improvements for a carotid blood flow measurement robotic system. This robotic system is composed of a serial robot with a wrist having a 6-DOF parallel mechanism. Main focus is to enhance the workspace performance of the wrist. Thus, a workspace analysis is carried out by referring to a built prototype that is named as WTA-1R (Waseda-Tokyo women's medical Aloka blood flow measurement system no.1 Refined). Then, mechanical design enhancements are proposed.

In recent years there has been an ever increasing amount of research and development of technologies and methods to improve the quality and the performance of advanced surgery. In other fields several training methods and metrics have been proposed, both to improve the surgeon's abilities and also to assess her/his skills. For neurosurgery, however, the extremely small movements and sizes involved have prevented until now the development of similar methodologies and systems. In this paper we present the development of an ultra-miniaturized Inertial Measurement Unit and its application for the evaluation of the performance in a simple pick and place scenario. This analysis is a preliminary yet fundamental step to realize a better training/evaluation system for neurosurgeons, and to objectively evaluate and understand how the neurosurgery is performed.

The emerging field of medical robotics is aiming in introducing intelligent tools to perform medical procedures. In particular, robotic researchers have been proposed advanced medical training systems to enhance motor dexterities of trainees. An efficient medical training system should be designed to simulate real-world conditions and to assure their effectiveness as the representation of the motor skills often differs among trainees. Up to now, several training simulators have been developed by medical companies designed to reproduce with high fidelity the human body. However, such devices are not designed to provide any information to trainees. Therefore, we have proposed the development of a Patient Robot which embeds sensors and actuators into a conventional human model. Due to its complexity, as a first approach; we are presenting the development of a suture training system designed to simulate the real-world task conditions as well as providing quantitative assessments. In particular; the Waseda-Kyotokagaku Suture No.2 Refined II is presented, which includes a new evaluation function to provide more detailed information of the task. A set of experiments were proposed to analyze the performance of trainees. From the experimental results, we could confirm its effectiveness to detect differences of the performance of trainees.

The research on the development of musical performance robots has been particularly intensified on the last decades. In fact, the development of anthropomorphic robots able of playing musical instruments have been served as a mean for understanding the human motor control from an engineering point of view as well as understanding how to enable the communication between human and robots from an emotional point of view. In particular, our research aims in the development of an anthropomorphic saxophonist robot which is able not only of performing a musical score; but also to interact with other musical performance robots (i.e. Waseda Flutist Robot) at the emotional level of perception. In this year, we have focused on the mechanical design of an anthropomorphic robot Waseda Saxophonist Robot No. 1 (WAS-1); which has been designed for playing an alto saxophone. WAS-1 has a total of 15-DOFs which mechanically reproduces the following organs involved during the saxophone playing: lips (1-DOF), tongue (1-DOF), oral cavity, lungs (air pump: 1-DOF and air valve: 1-DOF) and fingers (11-DOFs). In order to verify the effectiveness of the production of sound, a set of experiments have been proposed. In particular, the characteristics of air flow-pressure, level of mechanical noise, and the ripple effect ratio are presented. Finally, a qualitative evaluation of the sound produced by WAS-1 is presented and discussed. From the experimental results, we have confirmed the effectiveness of the proposed mechanisms to produce the saxophone sound.

Many researchers have studied on walking stability controls for biped robots. Most of them are highly accurate acceleration controls based on the mechanics model of the robot. However, the control algorithms are difficult to be used for human-carrying biped robots due to modeling errors. In the previous report, we proposed the landing pattern modification method, but it had a problem that a foot landing impact increased when a walking cycle was short. So, we propose a new terrain-adaptive control reducing a landing-impact force. To increase a concave terrain adaptation, we set a target landing position beneath a reference level. To reduce the landing-impact force, we change the position gain control value to a small value at a swing phase. Moreover, we set landing-foot speed at zero when the foot landing is detected by the force sensor mounted on a foot. To follow uneven terrain, a virtual spring is applied along the vertical direction after detecting a foot-landing on a ground, and a virtual compliance control is applied to the roll and pitch axes. In a stable walk while carrying a 65 kg human on uneven terrain, the new control method decreased the landing-impact force than the previous terrain-adaptive control.

The rapid increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms. For this purpose; in this paper, we are presenting our approach to introduce first year undergraduate students of the Department of Modern Mechanical Engineering the basics of robotics systems. In particular, the details of the inverted pendulum system based on the robotic education kit RoboDesigner and the development of a two-wheeled inverted pendulum mobile robot are detailed. The first system is basically used by students of the Mechatronics Laboratory (2) where they receive lectures of the content of each proposed topic and then, a set of practical experiments are done. On the other hand, in order to foster the creativity of undergraduate students of engineering fields, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 1 (WV-1) has been proposed. Different kinds of experiments were proposed to confirm the possibility of implementing controllers as well as changing physical properties of the system to observe differences on the response of the system. From the experimental results, we could confirm the effectiveness of the proposed systems to control the angle of pendulum respect to the body base.

In recent years, due to the increasing rate of elderly people in Japan, the needs to detect adults' diseases at the early stage becomes a high priority. In particular, an increased interest in detecting heart and cerebrovascular diseases at an early stage may allow clinicians to begin treatment sooner (when more treatment options are available), when interventions are generally more effective and less expensive. For this purpose, the introduction of robotic-assisted technology has advantages in terms of repetitiveness and accuracy of the measurement procedure. Therefore, at Waseda University, we have proposed the development of a carotid blood flow measurement system to support doctors while using ultrasound diagnostic equipments to detect arteriosclerosis and myocardial ischemia by measuring wave intensity. In this paper, the Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement System No. 1 Refined II (WTA-1RII) is detailed. The WTA-1RII is composed by an ultrasound diagnostic system and a probe-supporting robotic device. The robotic device is composed by a parallel link manipulator (for fine adjustment) and a passive arm (for rough positioning). The WTA-1RII has improved the design of the gravity compensation mechanism (composed by a constant force spring attached to a slide guide). In addition, a genetic algorithm has been implemented to determine the optimal link's position of the 6-DOF parallel manipulator to increase the workspace. Finally, a set of experiments were carried out to determine the usability of the proposed system.

The bipedal humanoid robot WABIAN-2R is developed to simulate human locomotion. Performing a walking motion requires a high torque at the ankle joint. WABIAN-2R consists of harmonic gears in its driveline system which increases the weight of each leg and respectively decreases the energy economy. However, using a spring mechanism instead of high gear ratio transmission could decrease the energy used during walking motion. Therefore, the idea of installing the dynamic walking techniques to WABIAN-2R is proposed. Using computer simulation the design of the ankle joint is modified by adding a spring mechanism and controlled by twisting the joint to set the required torque. Based of dynamic simulation an important step toward developing the passive dynamics walking into the advanced complex humanoid robots is been purposed.

Up to now, different kinds of musical performance robots (MPRs) have been developed. MPRs are designed to closely reproduce the required motor skills displayed by humans in order to play musical instruments. Our research at Waseda University has been focused on developing an anthropomorphic flutist robot. As a result of our research, the Waseda Flutist Robot No. 4 Refined IV (WF-4RIV) has been designed to mechanically reproduce the human organs involved during a flute-playing performance. Although the WF-4RIV is able to play the flute nearly similar to the performance of an intermediate player, further improvements in terms of cognitive capabilities are still required (i.e., autonomously improve the quality of the sound during performance based on the sound processing). For this purpose, in this paper, we present the implementation of an Auditory Feedback Control System (AFCS) designed to enable the flutist robot to analyze the flute sound during a performance (in a similar way professional flutists practice before a performance is held). The AFCS is composed of three subsystems (which are detailed in this paper): WF-4RIV&apos;s Control System, Expressive Music Generator and Pitch Evaluation System. A set of experiments was proposed to verify the effectiveness of the proposed AFCS to control the air pressure and to detect/correct faulty notes during a performance. From the experimental results, we confirm the improvements on the flute sound produced by the robot. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2009

The purpose of this study was to develop a robotic endoscope that is low invasive, easy to operate and capable of locomotion from the rectum to the appendix in the human body. We believe that it would contribute to relieving pain in patients. We therefore developed a robotic endoscope that consists of a front and rear body with clockwise and anticlockwise helical fins, respectively. The front and rear bodies are connected via a DC motor. This robot moves forward in the colon by rotating the front body in the clockwise direction and the rear body in the anticlockwise direction. In addition, the radius of each helical fin can be changed by blowing air into a balloon implemented under each fin using an air compressor. Before experiments with animals, we performed experiments to evaluate the mechanical performance and safety of the robot. We confirmed that the maximum radius of the fins was less than the maximum radius of the colon by blowing air continuously into the balloons. We then confirmed that the robot can locomote in the colon without invasion of scratch and make short hole by performing an in-vivo experiment in live swine.

The rapidly increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms. For this purpose; in this paper, we are presenting our approach to introduce first year undergraduate students of the Department of Modern Mechanical Engineering the basics of robotics systems. In particular, the details of curricula of the Mechatronics Laboratory (1) and (2) are explained. In both lessons, the students receive lectures of the content of each proposed topic and then, a set of practical experiments are done. On the other hand, in order to foster the creativity of undergraduate students of engineering fields, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 2R (WV-2R) has been proposed. Regarding the Mechatronics Laboratory, questionnaires were proposed to obtain information from the students about their impressions of the lessons. From the comments collected from the questionnaires, we observed the advantages of the proposed curricula to introduce them about robot technology. On the other hand, different kinds of experiments were proposed to confirm the possibility of implementing controllers as well as changing physical properties of the system to observe differences on the response of the system.

The rapidly increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms, by introducing in simple and efficient ways the basic components of robots as well as their application for solving real-world problems. In Japan, the proliferation of amateur robot contests has been introduced to motivate their interest to get involved in the robotics field. This is not only the case for tournaments supported by local governments and private companies. Several universities along Japan have been implementing Project-Based Learning (PBL) within their curricula as introduction for Mechatronic. For this purpose, at Waseda University, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 2 (WV-2R) has been proposed. In this paper, an overview of the research results is detailed. Even that in many universities around the world has been promoting the introduction of robotic technology, little discussion has been done to analyze from an ethical point of view. In this paper, some issues related to both Robot Education and Engineering Ethical Education are give based on experiences carried out in Japan. Then, some points regarding the integration of RoboEthics Education are pointed out for discussion.

The rapidly increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms. For this purpose; in this paper, we are presenting our approach to introduce first year undergraduate students of the Department of Modern Mechanical Engineering the basics of robotics systems. In order to foster the creativity of undergraduate students of engineering fields, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 2 (WV-2R) has been proposed. Different kinds of experiments were proposed to confirm the possibility or implementing controllers as well as changing physical properties of the system to observe differences on the response of the system. From the experimental results, we could confirm the effectiveness of the proposed systems to control the angle of pendulum respect to the body base as well as by changing the radius of the wheel.

The Waseda Flutist Robot is able to play the flute at the level of an intermediate human player. This ability opens a wide field of possibilities to research human-robot musical interaction. This research is focused on enabling the flutist robot to interact more naturally with musical partners in the context of a Jazz band. For this purpose a Musical-Based Interaction System (MbIS) has been proposed to enable the robot to process both visual and aural cues coming throughout the interaction with musicians. In a previous publication, we have concentrated on the implementation of visual communication techniques. We created an interaction interface that enabled the robot to detect instrument gestures of partner musicians during a musical performance. Two computer vision approaches were implemented to create a two-skill-level interface for visual human-robot interaction in a musical context. In this paper we focus on the aural perception system of the robot. The method introduced here enables the robot to, a suitable environment provided, detect the tempo and harmony of a partner musician's play, with a specific focus on improvisation. We achieve this by examining the rhythmical and harmonic characteristics of the recorded sound. We apply the same approach to amplitude and frequency spectrum, thus, in the former case tracking amplitude transients. In the latter case, as we focus on communication with monophonic woodwind instruments, we follow the most prominent peak in the frequency spectrum. We specifically use a similar technique for the audio analysis as we did for our previous research on motion tracking. From the experimental results, we have shown that after implementing our algorithm the robot is able to correctly recognize a number of rhythms and harmonies. It is able to engage in a simple form of stimuli and reaction play with a human musician.

The rapidly increase of personal robotic platforms and their applications in Japan represents a great challenge for universities to introduce undergraduate students the basic knowledge required to develop intelligent automated mechanisms. For this purpose; in this paper, we are presenting our approach to introduce first year undergraduate students of the Department of Modern Mechanical Engineering the basics of robotics systems. In order to foster the creativity of undergraduate students of engineering fields, we focused in developing an education tool designed to introduce at different educational levels the principle of developing mechatronic systems. In particular, the development of an inverted pendulum mobile robot Waseda Wheeled Vehicle No. 2 (WV-2R) has been proposed. Different kinds of experiments were proposed to confirm the possibility or implementing controllers as well as changing physical properties of the system to observe differences on the response of the system. From the experimental results, we could confirm the effectiveness of the proposed systems to control the angle of pendulum respect to the body base as well as by changing the radius of the wheel.

During several decades, the research at Waseda University has been focused on developing anthropomorphic robots able of performing musical instruments. More recently, the authors have succeeded in developing a human-like robot able of playing the alto saxophone. As a result of our research efforts, the Waseda Flutist Robot WF-4RIV and the Waseda Saxophonist Robot WAS-1 have been designed to reproduce the human player performance. Therefore, as a long-term goal, we tire proposing to enable the interaction between musical performance robots (i.e. robots orchestra). Such approach may enable us not only to propose new ways of musical expression, but also we may contribute to the better understanding of some of the mechanisms that enable the communication of humans in musical terms. In general terms, the communication of humans within an orchestra is a special case of conventional human social behavior. Rhythm, harmony and timbre of the music played represent the emotional states of the musicians. Of course, we are not considering a musical performance robot (MPR) just as a mere sophisticated MIDI instrument. Instead, its human-like design and the integration of perceptual capabilities may enable to act on its own autonomous initiative based on models which consider its own physical constrains. Due to the complexity of our long-term goal, in this paper, we sire presenting our first steps towards enabling the interaction between musical performance robots. In particular, the details of the musical performance control systems are detailed.;flanks to the use of MIDI data, we performed preliminary experiments to enable a duet performance between the WF-4RIV and the WAS-I. We expect in the future; as a result of our research, we may enable a single anthropomorphic robot to perform different kinds of woodwind instruments as well as liable to interact at with level of perceptual capabilities (like human does).

The research on the Waseda Flutist Robot
since 1990, has been carried out as an approach to understand the human motor control from an engineering point of view as well as introducing novel ways of musical teaching. Thanks to the improvements on the technical skills of WF-4RIV, we have enabled the flutist robot to enhance its musical expressiveness. As authors have being developing basic cognitive capabilities on the WF-4RIV
we have proposed as a long-term goal to enable musical performance robots (MPRs) to interact with musical partners. For this purpose, we have proposed two approaches: implementing more advanced cognitive capabilities on the WF-4RIV and developing a new musical performance robot. In this paper, we have focused our research on developing an anthropomorphic saxophonist robot as a benchmark to understand better how the interaction with musical partners can be facilitated. Thanks to our experience on developing the flutist robot, we have succeeded in developing the WAseda Saxophist Robot no. 1 (WAS-1), which is composed of 15-DOFs. In this paper, in particular, we present the details of the mechanical and control systems. A set of experiments were proposed to compare the saxophone performance as well as the production of vibrato of the WAS-1 compared with human players. ©2009 IEEE.

Many researchers have studied on walking stability controls for biped robots. Most of them are highly accurate acceleration controls based on the mechanics model of the robot. However, the control algorithms are difficult to be applied to human-carrying biped robots due to modeling errors. In the previous report, we proposed the landing pattern modification method, but it had a problem that a foot landing impact increased when a walking speed became fast. So, we propose a new terrain-adaptive control that can reduce a landing.. impact force. To increase a concave terrain adaptation, e set a target landing position beneath a reference level. To reduce the landing-impact force, we change the position gain control value to a small value at a swing phase. Moreover, we set landing-foot speed at zero after detecting a foot-landing by the force sensor mounted on a foot. To follow uneven terrain, a virtual spring is installed to the vertical direction after detecting a foot-landing on a ground, and a virtual compliance control is applied to the roll and pitch axes. In a stable walk while carrying a 65 kg human on uneven terrain, the new control method decreased the landing-impact force than the previous terrain-adaptive control.

We have developed a new, three dimensional vocal tract mechanical model for an anthropomorphic talking robot WT-7R (Waseda Talker No. 7 Refined), to improve the resonance of the vocal tract. The Waseda Talker robot series aims to reproduce the human speech mechanism with three-dimensional accuracy. The tongue of the previous model, WT-7 (Waseda Talker No. 7), was made of rigid links and covered with a thermoplastic rubber (Septon). This mechanism could deform the tongue shape and work as a part of the vocal tract, however, the cover thickness was not sufficient enough to prevent sound leakage, and did not have sufficient resonance. As a result, the produced sounds were unclear. To resolve this problem, the inner area of the tongue was filled with liquid. We experimented to select the filling liquid which is minimizes damage to the Septon cover and provides adequate resonance characteristics. The ethylene glycol was selected because it does little damage to the Septon and is relatively non-flammable. An oil seal and liquid gasket prevent leakage into the robot. WT-7 also has problems with its tongue link deformation range and open lip control range-these problems were also addressed. The improvements made the vowel production of WT-7R clearer than that of the previous robot, and the bandwidth of the formant peak in spectral analysis became sharper.

Up to now, different kinds of musical performance robots (MPRs) have been developed. MPRs are designed to closely reproduce the required motor skills displayed by humans in order to play musical instruments. Our research at Waseda University has been focused on developing an anthropomorphic flutist robot. As a result of our research, the Waseda Flutist Robot No. 4 Refined IV (WF-4RIV) has been designed to mechanically reproduce the human organs involved during a flute-playing performance. Although the WF-4RIV is able to play the flute nearly similar to the performance of an intermediate player, further improvements in terms of cognitive capabilities are still required (i.e., autonomously improve the quality of the sound during performance based on the sound processing). For this purpose, in this paper, we present the implementation of an Auditory Feedback Control System (AFCS) designed to enable the flutist robot to analyze the flute sound during a performance (in a similar way professional flutists practice before a performance is held). The AFCS is composed of three subsystems (which are detailed in this paper): WF-4RIV&apos;s Control System, Expressive Music Generator and Pitch Evaluation System. A set of experiments was proposed to verify the effectiveness of the proposed AFCS to control the air pressure and to detect/correct faulty notes during a performance. From the experimental results, we confirm the improvements on the flute sound produced by the robot. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2009

In recent years, due to the increasing rate of elderly people in Japan, the needs to detect adults' diseases at the early stage becomes a high priority. In particular, an increased interest in detecting heart and cerebrovascular diseases at an early stage may allow clinicians to begin treatment sooner, when interventions are generally more effective and less expensive. Recently, the Wave Intensity (WI) has been proposed as a new hemodynamic index that provides information about the dynamic behavior of the heart and the vascular system and their interaction. However; the repetitiveness and accuracy of the WI measurement depend on the precision of the positioning of the ultrasound probe. Therefore a positioning device for ultrasound probe is required. Such a device should not only be used to keep the position but also for the fine positioning of the probe. For this purpose, at Waseda University, we have proposed the development of a robot system to assist a carotid blood flow measurement using ultrasound diagnostic equipments. In this paper, the development of Waseda-Tokyo Women's Medical-Aloka Blood Flow Measurement System No. 1 Refined II (WTA-1RII is detailed. The system consists of an ultrasound diagnostic device, a 6-DOFs parallel link manipulator, a serial link passive arm, ball joint, and a joystick type controller. The WTA-1RII has improved the design of the gravity compensation mechanism. In addition, a genetic algorithm has by implemented to determine the optimal link's position of the 6-DOFs parallel manipulator to increase the workspace. Finally, a set of experiments were carried out to determine the usability of the proposed system.

Up to now, different kinds of musical performance robots (MPRs) have been developed. MPRs are designed to closely reproduce the required motor skills displayed by humans in order to play musical instruments. Our research at Waseda University has been focused on developing an anthropomorphic flutist robot. As a result of our research, the Waseda Flutist Robot No. 4 Refined IV (WF-4RIV) has been designed to mechanically reproduce the human organs involved during a flute-playing performance. Although the WF-4RIV is able to play the flute nearly similar to the performance of an intermediate player, further improvements in terms of cognitive capabilities are still required (i.e., autonomously improve the quality of the sound during performance based on the sound processing). For this purpose, in this paper, we present the implementation of an Auditory Feedback Control System (AFCS) designed to enable the flutist robot to analyze the flute sound during a performance (in a similar way professional flutists practice before a performance is held). The AFCS is composed of three subsystems (which are detailed in this paper): WF-4RIV&apos;s Control System, Expressive Music Generator and Pitch Evaluation System. A set of experiments was proposed to verify the effectiveness of the proposed AFCS to control the air pressure and to detect/correct faulty notes during a performance. From the experimental results, we confirm the improvements on the flute sound produced by the robot. (C) Koninklijke Brill NV, Leiden and The Robotics Society of Japan, 2009

We developed an anthropomorphic talking robot, Waseda Talker No. 6 (WT-6), which generates speech sounds by mechanically simulating articulatory motions and aero-acoustic phenomena. WT-6 possesses 17 degrees of freedom (DOF): a 5-DOF tongue, 1-DOF jaws, 4-DOF lips, a nasal cavity, and a 1-DOF soft palate as articulators
and 5-DOF vocal cords and 1-DOF lungs as vocal organs. The vocal cords, tongue, and lips are made from the thermoplastic rubber Septon, whose elasticity is similar to that of human tissue. WT-6 has three-dimensional (3D) lips, tongue, jaw, and velum, which form the vocal tract structure. It also has an independent jaw opening/closing mechanism. The previous robot in the series had a two-dimensional tongue and could not produce human-like tongue shape. The new tongue can form 3D shapes, and thus, is able to produce more realistic vocal tract shapes. The vocal cord model consists of two folds, and is constructed with a structure similar to the biomechanical structure of human vocal cords. These vocal cords can vibrate in complex phases, similar to those of a human. With these mechanisms, the robot can reproduce human speech in a more biomechanical manner, and thus, can produce a voice closer to that of a human. © 2008 Trans Tech Publications, Switzerland.

Up to now, there is no widely accepted quantitative evaluation scheme. Nowadays, an objective structured clinical examination has been proposed as a modern type of examination often used in medicine to test skills such as medical procedures, etc. The assessment of skills is realized by practical exams, in which students are evaluated by experienced examiner using a check list. However, the examiner lacks of information which cannot be obtained trough the simple observation of the task. Thanks to the recent advances in robot technology in embedded systems, etc.; more advanced evaluation tools can be conceived. For this reason, at Waseda University, we have proposed the development of a patient robot as an advanced evaluation tool to provide more detailed information of the task. As a first approach of our long-term research target, we have proposed the development of a suture/ligature training system which provides quantitative information of the movement of a dummy skin as well as information of the quality of task. In this paper; we describe the functionalities of the newest version, the Waseda-KyotoKagaku Skin No.2 Refined (WKS-2R), which has been designed to provide quantitative information of the task. In addition, we are proposing a new evaluation function which includes performance indexes and weighting coefficients. As a first approach, the weighting coefficients were determined by using the discriminant analysis. A set of experiments were proposed to confirm the effectiveness of the proposed evaluation function. From the preliminary results, the evaluation function was useful in detecting differences among different levels of expertise as well as detecting improvements during the training process by computing the learning curve.

In the aging society, more effective rehabilitation/welfare instruments to support seniors and disabled persons are required. However, it becomes difficult the evaluation of such instruments for safety reasons. Therefore, we suggest the use of a humanoid robot, which is able to display human motions, instead of a human to evaluate such instruments as an experimental subject. The use of robots for measurement purposes is safe and gives us the quantitative data for improving rehabilitation/welfare instruments. Recently, we have developed the new humanoid robot as a human motion simulator, WABIAN-2. This robot can walk autonomously with the knees stretched like a human by using waist motion, and also it can walk by physically interacting with a walk-assist machine. In this paper, the experiments are focused verifying if the WABAIN-2 can be considered as a human motion simulator to move a walk-assist machine while walking.

This paper describes the mechanism of a 16 d.f. biped walking machine, Waseda biped humanoid robot-2 lower limb (WABIAN- 2LL), which has two 7 d.f. legs and a 2 d.f. waist actuated by DC servo motors with reduction gears. WABIAN-2LL is designed with large movable angle ranges like those of a human. Its height and weight are 1200 mm and 40 kg, respectively. It is able to walk with its knees stretched using the redundancy of the legs and to move around an object using a hip-bending motion without touching the object. A knee-stretched locomotion pattern generation is also proposed in this paper, which separately creates joint angles in a supporting and a swinging phase. During knee-stretched walking, the joint rate of the knee will approach infinitely when the knee is stretched. This singularity problem is solved by using the motion of the waist, not the posture of the trunk. The effectiveness of the mechanisms and pattern generations of WABIAN-2LL is verified through dynamic walking experiments.

The aim of this paper is to create an interface for human-robot interaction. Specifically, musical performance parameters (i.e. vibrato expression) of the Waseda Flutist Robot No.4 Refined IV (WF-4RIV) are to be manipulated. Our research is focused on enabling the WF-4RIV to interact with human players (musicians) in a natural way. In this paper, as a first approach, a vision processing algorithm, that is able to track the 3D-orientation and position of a musical instrument, was developed. In particular, the robot acquires image data through two cameras attached to its head. Using color histogram matching and a particle filter, the position of the musician's hands on the instrument are tracked. Analysis of this data determines orientation and location of the instrument. These parameters are mapped to manipulate the musical expression of the WF-4RIV, more specifically sound vibrato and volume values. We present preliminary experiments to determine if the robot may dynamically change musical parameters while interacting with a human player (i.e. vibrato etc.). From the experimental results, we may confirm the feasibility of the interaction during a performance, although further research must be carried out to consider the physical constraints of the flutist robot

The emerging field of medical robotics is aiming in introducing intelligent tools. More recently, thanks to the innovations on robot technology (IRT), advanced medical training systems have been introduced to improve the skills of trainees. The principal challenges of developing efficient medical training systems are simulating real-world conditions and assuring their effectiveness. Up to now, different kinds of medical training devices have been developed which are designed to reproduce with high fidelity the human anatomy. Due to their design concept, the evaluation of progress of the trainees is based on subjective assessments limiting the understanding of their effectiveness. In this paper, we are presenting our research towards developing a patient robot designed to simulate the real-world task conditions and providing objective assessments of the training achievements. Due to its complexity; in this paper, we are presenting as a first approach the development of the Waseda-Kyotokagaku Airway No. 1R (WKA-1R) which includes a human patient model with embedded sensors in order to provide objective assessments of the training progress. In particular, we have proposed an evaluation function to quantitatively evaluate the task performance by determining the weighting of coefficients. In order to determine the weighting of coefficients, we applied discriminant analysis. In order to determine the effectiveness of the proposed evaluation function to detect differences among different levels of expertise, an experimental setup was carried out. From the experimental results, we could find a significant difference between both groups (P&lt;0.05).

We have developed a vocal control method, based on forward and inverse models, to allow the anthropomorphic talking robot Waseda Talker No. 7 (WT-7) to produce various kinds of voices. The control parameters of the vocal cords on WT-7 are pressure, vocal cord tension and glottal opening, and the acoustic parameters are sound pressure, sound pitch and spectrum slope. The relationships among these parameters are complicated and difficult to model using conventional methods. Here we present a neural network (NN) control method. The learning process consists of creation of the NN forward model by back propagation methods and optimization of the inverse model using the forward model. In addition, a real-time auditory feed-back mechanism is used to reduce the error between the target and the generated acoustic parameters. Using this method, the control parameters can be adjusted to follow the target voice well.

A new humanoid bipedal robot WABIAN-2R was developed to simulate human motion. WABAIN-2R is able to perform similar human-like walking motion. Moreover, the robot is able to perform walking motions with a passive walk-assist machine. However, walking with an active walk-assist machine is expected to be unstable. Conducting this experiment is highly risky and costly. Therefore, we had developed a dynamic Simulator in order to test walking robot with walk-assist machine before conducting it in real simulation.

The emerging field of medical robotics is aiming in introducing intelligent tools. More recently, thanks to the innovations on robot technology (IRT), advanced medical training systems have been introduced to improve the skills of trainees. The principal challenges of developing efficient medical training systems are simulating real-world conditions and assuring their effectiveness. Up to now, different kinds of medical training devices have been developed which are designed to reproduce with high fidelity the human anatomy. Due to their design concept, the evaluation of progress of the trainees is based on subjective assessments limiting the understanding of their effectiveness. In this paper, we are presenting our research towards developing a patient robot designed to simulate the real-world task conditions and providing objective assessments of the training achievements. Due to its complexity; in this paper, we are presenting as a first approach the development of the Waseda-Kyotokagaku Airway No. 1R (WKA-1R) which includes a human patient model with embedded sensors in order to provide objective assessments of the training progress. In particular, we have proposed an evaluation function to quantitatively evaluate the task performance by determining the weighting of coefficients. In order to determine the weighting of coefficients, we applied discriminant analysis. In order to determine the effectiveness of the proposed evaluation function to detect differences among different levels of expertise, an experimental setup was carried out. From the experimental results, we could find a significant difference between both groups (P&lt;0.05).

Personal robots and robot technology (RT)-based assistive devices are expected to play a major role in our elderly-dominated society, with an active participation to joint works and community life with humans, as partner and as friends for us. In particular, these robots are expected to be fundamental for helping and assisting elderly and disabled people during their activities of daily living (ADLs). To achieve this result, personal robots should be capable of human-like emotion expressions; in addition, human-like bipedal walking is the best solution for the robots which should be active in the human living environment. Although several bipedal robots and several emotional expression robots have been developed in the recent years, until now there was no robot which integrated all these functions. Therefore we developed a new bipedal walking robot, named KOBIAN, which is also capable to express human-like emotions. In this paper, we present the design and the preliminary evaluation of the new emotional expression head. The preliminary results showed that the emotion expressed by only the head cannot be really easily understood by the users. However, the presence of a full body clearly enhances the emotion expression capability of the robot, thus proving the effectiveness of the proposed approach.

Personal robots and robot technology (RT)-based assistive devices are expected to play a major role in our elderly-dominated society, with an active participation to joint works and community life with humans, as partner and as friends for us. The authors think that the emotion expression of a robot is effective in joint activities of human and robot. In addition, we also think that bipedal walking is necessary to robots which are active in human living environment. But, there was no robot which has those functions. And, it is not clear what kinds of functions are effective actually. Therefore we developed a new bipedal walking robot which is capable to express emotions. In this paper, we present the design and the preliminary evaluation of the new head of the robot with only a small number of degrees of freedom for facial expression

Up to now, different kinds of musical performance robots (MPRs) and robotic musicians (RMs) have been developed. MPRs are designed to closely reproduce the motor skills displayed by humans in order to play musical instruments. From this approach, MPRs are used as benchmarks to study the human motor control from an engineering point of view and to understand better the human-robot interaction from a musical point of view. In contrast, RMs are conceived as automated mechanisms designed to create new ways of musical expression from a musical engineering point of view. Our research, at Waseda University, has been focused on developing an anthropomorphic flutist robot. Our research aims in studying the human motor control from an engineering point of view, understanding the ways to facilitate the human-robot interaction and proposing new applications for humanoid robot in musical terms. As a result of our research, the Waseda Flutist Robot No.4 Refined IV (WF-4RIV) has been developed. In a previous research, we focused on improving the mechanical system in order to enhance the clarity of the sound. However, we require performing further improvements to the control system in order to enable the robot to autonomously improve the quality of the sound during the flute performance. For this purpose, we proposed to implement an auditory feedback control system on the flutist robot. The proposed system is composed by a music expressive generator, feed-forward air pressure control system and a pitch evaluation module. From the experimental results with the WF-4RIV, we could confirm the improvements on the flute performance.

Our research aims to develop an anthropomorphic flutist robot as a benchmark for the better understanding of interaction between musicians and musical performance robots from a musical point of view. As a long-term goal of our research, we would like to enable such robots to play actively together with a human band, and create novel ways of musical expression. For this purpose, we focus on enhancing the perceptual capabilities of the flutist robot to process musical information coming from the aural and visual perceptual channels. In this paper, we introduce, as a first approach, a hands-free gesture-based control interface designed to modify musical parameters in real-time. In particular, we describe a set of virtual controllers, that a composer can manipulate through gestures of with a musical instrument. The gestures are identified by 2-D motion sensitive areas which graphically represent common control interfaces used in music production. The resulting information from the vision processing is then transformed into MIDI messages, which are subsequently played by the flute robot. In order to verify the effectiveness of the proposed gestural interface, we performed experiments to musically interact with musical partners. ?From the experimental results we concluded that our method satisfies the technical and idiosyncratic requirements for being a suitable tool for musical performance.

Up to now, different kinds of musical performance robots (MPRs) have been developed. MPRs are designed to closely reproduce the required motor skills displayed by humans in order to play musical instruments. Our research, at Waseda University, has been focused on developing an anthropomorphic flutist robot. In this year, we have succeeded in developing the Waseda Flutist Robot No.4 Refined IV (WF-4RIV); which has improved the design of the mouth mechanism and reproduced the anatomy of the human lips better. In addition, the control system was improved to enable the robot to autonomously improve the quality of the sound during performance. For this purpose, we proposed to implement a new performance control system. From the experimental results, we confirm the improvements on the flu e sound produced by the robot.

The research on human-robot interaction (HRI) has been an emerging topic of interest for both basic research and customer application. The studies specially focus on behavioral and cognitive aspects of the interaction and the social contexts surrounding it. HRI issues have long been a part of robotics research because the goal of fully autonomous capability has not been met yet. One of the most challenging problems is giving the robots an understanding of how to interact with human beings at the same logical level so that they may function not as passive tools, but rather as active agents that can drive the human interaction, instead of merely reproducing a sequence of movements. Hence, these robots must have higher level cognitive functions that include knowing how to reason, when to perceive and what to look for, how to integrate perception and action under changing conditions, etc. These functions will enable robots to perform more complex tasks which require tight human interaction; consequently, the robots can perform high level interactions such as teaching motor skills to unskilled people. Such functions include the extraction of symbolic descriptions based on the integration of the information coming through the robot's sensors and the analysis of these descriptions to decide the action to be carried out in order to improve the humans' performances. In this paper; in particular, some approaches and applications towards enhancing the understanding of the human performance to implement the evaluation module of the proposed General Transfer Skill System (from robot to human) are described.

The aim of our research is to develop an anthropomorphic flutist robot that on the one hand reproduces the human motor skills required for playing the flute, and on the other hand displays cognitive capabilities for interacting with other (human) musicians. In this paper, we detail the recent mechanical improvements on the Waseda Flutist Robot (WF-4RIV), enhancing the realistic production of the flute sound. In particular, improved lips, oral cavity and tonguing are introduced and their mechanisms described: The possibility to deform the lip shape in 3-DOF, allows us to accurately control the characteristics of the air-stream (width, thickness and angle). An improved tonguing mechanism (1-DOF) has been designed to reproduce double tonguing. Furthermore we present the implementation of a real-time interaction system with human partners. We developed, as a first approach, a vision processing algorithm to track the 3D-orientation and position of a musical instrument: Image data is recorded using two cameras attached to the head of the robot, and processed in real-time. The proposed algorithm is based on color histogram matching and particle filter techniques to follow the position of a musician's hands on an instrument. Data analysis enables us to determine the orientation and location of the instrument. We map these parameters to control musical performance parameters of the WF-4RIV, such as sound vibrato and sound volume. A set of experiments were proposed to verify the effectiveness of the proposed tracking system during interaction with a human player. We conclude, that the quality of the musical performance of the WF-4RIV and its capabilities to interact with musical partners, have been significantly improved by the implementation of the techniques, that are proposed in this paper.

Up to now, different kinds of musical performance robots have been developed. MPRs are designed to closely reproduce the human organs involved during the playing of musical instruments. Our research on the Waseda Flutist Robot has been focused on clarifying the human motor control from an engineering point of view. As a result, the Waseda Flutist Robot No. 4 Refined W (WF-4RIV) is able of playing the flute nearly similar to an intermediate player. Thanks to the human-like design and the advanced technical skills displayed by the WF-4RIV, novel ways of musical education can be conceived. In this paper; the General Transfer Skill System (GTSS) is implemented on the flutist robot, towards enabling the automated transfer of technical skills from the robot to flutist beginners. A set of experiments are carried out to verify the evaluation and interaction modules of the GTSS. From the experimental results, the robot is able of quantitatively evaluating the performance of beginners, and automatically recognizing the melodies performed by them.

It is well known that the massage therapy is useful for the rehabilitation of various diseases. Although various apparatus have been developed for the massage of the torso and limbs, a machine to perform precise massage therapy to maxillofacial region is not developed yet. Therefore, we developed a robot system that provides massage therapy to maxillofacial region. The name of our newly developed robot was WAO-1. WAO-1 has been designed to perform appropriate massage to the patients with dry mouth, etc. WAO-1 is composed by two 6-degree of freedom arms with plungers attached at the end-effectors. The massage is applied to the patient by controlling the force and position of the plunger (virtual compliance). As a preliminary step of the clinical application, a simulation therapy of robotic massage to stimulate salivary flow from parotid gland was performed. The dynamic force on patient's head during the massage using WAO-1 was evaluated. The results suggested that WAO-1 could perform equivalent massage to human hand. We expect that WAO-1 will be useful to provide massage therapy to several patients with oral health problems. This will aim in reducing the therapy costs due to the need of human efforts when long-time therapies are needed. ©2008 IEEE.

We have developed a vocal control method, based on forward and inverse models, to allow the anthropomorphic talking robot Waseda Talker No. 7 (WT-7) to produce various kinds of voices. The control parameters of the vocal cords on WT-7 are pressure, vocal cord tension and glottal opening, and the acoustic parameters are sound pressure, sound pitch and spectrum slope. The relationships among these parameters are complicated and difficult to model using conventional methods. Here we present a neural network (NN) control method. The learning process consists of creation of the NN forward model by back propagation methods and optimization of the inverse model using the forward model. In addition, a real-time auditory feed-back mechanism is used to reduce the error between the target and the generated acoustic parameters. Using this method, the control parameters can be adjusted to follow the target voice well.

the goal of this study is to realize a biped humanoid robot as a human motion simulator; where a biped humanoid robot having an ability to mimic various human motions is used for testing welfare apparatuses. In this paper, a humanoid robot, WABIAN-2R, capable of not only human-like walking but also the emulation of disabled persons' walking is proposed. It has two 6-DOF legs, two 1-DOF feet, a 2-DOF pelvis, a 2-DOF trunk, two 7-DOF arms with 3-DOF hands, and a 3-DOF neck. In addition, an algorithm for generating walking patterns for emulations of disabled persons' gaits for each case of disabilities based on the ZMP criterion is described. Moreover, the emulation experiment of the hemiplegic gait of a subject was conducted to demonstrate the effectiveness of the pattern generation method and mechanism of WABIAN-2R as a human motion simulator.

This paper describes a static disturbance compensation control for a biped walking vehicle. To measure forces and moments caused by a passenger's motion, we use a 6-axis force/torque sensor placed under the passenger's seat. When small external force acts on a robot, only a reference ZMP trajectory is changed inside a support polygon. When large external force over a predetermined threshold force acts on a robot, a waist motion is changed. With only the proposed control, however, a robot cannot adapt to rapid disturbance changes. But we have already developed a dynamic disturbance compensation control, so by combining two controls, a human-carrying biped robot, Waseda Leg - No. 16 Refined V (WL-16RV) realized a stable dynamic walk under unknown external disturbances caused by passenger's static and dynamic motion. We confirmed the effectiveness of our proposal through experiments.

Object: The emerging field of medical robotics aims tointroduce intelligent tools for physician support. The main challenges for developing efficient medical robotic training systems are simulating real-world conditions of the task and assuring training effectiveness. High anatomic fidelity has been achieved in current systems, but they are limited to provide merely subjective assessments of the training progress. We simulated airway intubation using a unique medical robot and developed objective performance criteria to assess task performance. Materials and methods: A patient simulation robot was designed to mimic real-world task conditions and provide objective assessments of training progress. The Waseda' Kyotokagaku Airway No. 1R (WKA-1R) includes a human patient model with embedded sensors. An evaluation function was developed for the WKA-1R to quantitatively assess task performance. The evaluation includes performance indices and coefficient weighting. The performance indices were defined based on experiments carried out with medical doctors and from information found in the medical literature. The performance indices are: intubation time, jaw opening, incisor teeth force, cuff pressure, tongue force and tube position. To determine the weighting of coefficients, we used discriminant analysis. Results: Experiments were carried out with volunteers to determine the effectiveness of the WKA-1R to quantitatively evaluate their performance while performing airway management. We asked subjects from different levels of expertise (from anesthetists to unskilled) to perform the task. From the experimental results, we determined operator effectiveness using the proposed performance indices. We found a significant difference between the experimental groups by evaluating their performances using the proposed evaluation function (P &lt
0.05). Conclusions: The WKA-1R robot was designed to quantitatively acquire information on the performances of trainees during intubation procedures. From the experimental results, we could objectively determine operator effectiveness while providing quantitative task assessments. © CARS 2008.

Up to now, there is no widely accepted assessment of surgical skills. Nowadays, an objective structured clinical examination (OSCE) has been proposed as a modern type of examination often used in medicine to test skills. The assessment of skills is realized by practical exams, in which students are evaluated by experienced examiner using a check list. However, the examiner lacks of information which cannot be obtained through the simple observation of the task. Therefore, at Waseda University, we have proposed the development of a patient robot as an advanced evaluation tool to provide more detailed information of the task. As a first approach of our long-term research target, we have proposed the development of a suture/ligature training system which provides quantitative information of the movement of a dummy skin as well as information of the quality of task. Therefore in this paper, we are presenting the Waseda Kyotokagaku Suture No. 2 Refined II (WKS-2RII). The WKS-2RII has been designed to provide more detailed information of the task performance. Experiments were proposed to confirm the effectiveness of the proposed evaluation parameters to distinguish the differences among different training methods.

The bipedal humanoid robot WABIAN-2R is developed to simulate human locomotion. Performing a walking motion requires a high torque at the ankle joint. WABIAN-2R consists harmonic gears in its driveline system which increases the weight of each leg and respectively decreases the energy economy. Therefore, a new idea is proposed and developed in this paper through computer simulation to modify the design of the ankle joint by adding a spring mechanism instead of high gear ratio transmission. This helps to reduce the energy consumed while walking; by storing and returning part of the energy. Research presented in this paper proposes an important step toward developing the passive dynamics walking into the advanced complex humanoid robots.

The humanoid bipedal robot WABIAN-2R was developed to be used as human motion simulator. It is able to perform similar human-like walking motion. Moreover, the robot is able to perform walking motions with a walking support device. This walking device was moving passively helping the robot to move easily. However, to go further with this development, we have to test the robot using the walking device with different conditions such as activating its wheel motors. Conducting this experiment is expected to be highly risky and costly. Therefore, we had developed a dynamic simulator in order to test the performance of the robot using the walking support device before conducting it in real simulation.

The emerging field of medical robotics is aiming in introducing intelligent tools. More recently, thanks to the innovations on robot technology (IRT), advanced medical training systems have been introduced to improve the skills of trainees. The principal challenges of developing efficient medical training systems are simulating real-world conditions and assuring their effectiveness. Up to now, different kinds of medical training devices have been developed which are designed to reproduce with high fidelity the human anatomy. Due to their design concept, the evaluation of progress of the trainees is based on subjective assessments limiting the understanding of their effectiveness. In this paper, we are presenting our research towards developing a patient robot designed to simulate the real-world task conditions and providing objective assessments of the training achievements. Due to its complexity; in this paper, we are presenting as a first approach the development of the Waseda-Kyotokagaku Airway No. 1R (WKA-1R) which includes a human patient model with embedded sensors in order to provide objective assessments of the training progress. In particular, we have proposed an evaluation function to quantitatively evaluate the task performance by determining the weighting of coefficients. In order to determine the weighting of coefficients, we applied discriminant analysis. In order to determine the effectiveness of the proposed evaluation function to detect differences among different levels of expertise, an experimental setup was carried out. From the experimental results, we could find a significant difference between both groups (P&lt;0.05).

Behavior synchronization of humans during conversation and cooperative task has been studied in psychology. In robotics, several researchers also have been studying cooperative task between a human and a robot referring to these studies. However, mechanisms of behavior synchronization are still unclear because of complexity of human being. Therefore, referring to animal psychology, we propose a novel experimental methodology to study behavior synchronization through interaction experiments between a rat and a robot. We then developed small mobile robots and an experimental setup. This experimental setup consists of two open-fields. A robot and a rat are released into each open-field. The robot reproduces motion of the rat in the other open-field. Using this experimental setup we also performed a preliminary experiment to investigate behavior synchronization. In this paper, we describe the robot and the experimental setup. We also introduce result of the experiment briefly.

Up to now, different kinds of musical performance robots (MPRs) and robotic musicians (RMs) have been developed. MPRs are designed to closely reproduce the motor skills displayed by humans in order to play musical instruments. From this approach, MPRs are used as benchmarks to study the human motor control from an engineering point of view and to understand better the human-robot interaction from a musical point of view. In contrast, RMs are conceived as automated mechanisms designed to create new ways of musical expression from a musical engineering point of view. Our research, at Waseda University, has been focused on developing an anthropomorphic flutist robot. Our research aims in studying the human motor control from an engineering point of view, understanding the ways to facilitate the human-robot interaction and proposing new applications for humanoid robot in musical terms. As a result of our research, the Waseda Flutist Robot No.4 Refined IV (WF-4RIV) has been developed. In a previous research, we focused on improving the mechanical system in order to enhance the clarity of the sound. However, we require performing further improvements to the control system in order to enable the robot to autonomously improve the quality of the sound during the flute performance. For this purpose, we proposed to implement an auditory feedback control system on the flutist robot. The proposed system is composed by a music expressive generator, feed-forward air pressure control system and a pitch evaluation module. From the experimental results with the WF-4RIV, we could confirm the improvements on the flute performance.

Our research aims to develop an anthropomorphic flutist robot as a benchmark for the better understanding of interaction between musicians and musical performance robots from a musical point of view. As a long-term goal of our research, we would like to enable such robots to play actively together with a human band, and create novel ways of musical expression. For this purpose, we focus on enhancing the perceptual capabilities of the flutist robot to process musical information coming from the aural and visual perceptual channels. In this paper, we introduce, as a first approach, a hands-free gesture-based control interface designed to modify musical parameters in real-time. In particular, we describe a set of virtual controllers, that a composer can manipulate through gestures of with a musical instrument. The gestures are identified by 2-D motion sensitive areas which graphically represent common control interfaces used in music production. The resulting information from the vision processing is then transformed into MIDI messages, which are subsequently played by the flute robot. In order to verify the effectiveness of the proposed gestural interface, we performed experiments to musically interact with musical partners. ?From the experimental results we concluded that our method satisfies the technical and idiosyncratic requirements for being a suitable tool for musical performance.

Up to now, different kinds of musical performance robots (MPRs) have been developed. MPRs are designed to closely reproduce the required motor skills displayed by humans in order to play musical instruments. Our research, at Waseda University, has been focused on developing an anthropomorphic flutist robot. In this year, we have succeeded in developing the Waseda Flutist Robot No.4 Refined IV (WF-4RIV); which has improved the design of the mouth mechanism and reproduced the anatomy of the human lips better. In addition, the control system was improved to enable the robot to autonomously improve the quality of the sound during performance. For this purpose, we proposed to implement a new performance control system. From the experimental results, we confirm the improvements on the flu e sound produced by the robot.

The aim of our research is to develop an anthropomorphic flutist robot that on the one hand reproduces the human motor skills required for playing the flute, and on the other hand displays cognitive capabilities for interacting with other (human) musicians. In this paper, we detail the recent mechanical improvements on the Waseda Flutist Robot (WF-4RIV), enhancing the realistic production of the flute sound. In particular, improved lips, oral cavity and tonguing are introduced and their mechanisms described: The possibility to deform the lip shape in 3-DOF, allows us to accurately control the characteristics of the air-stream (width, thickness and angle). An improved tonguing mechanism (1-DOF) has been designed to reproduce double tonguing. Furthermore we present the implementation of a real-time interaction system with human partners. We developed, as a first approach, a vision processing algorithm to track the 3D-orientation and position of a musical instrument: Image data is recorded using two cameras attached to the head of the robot, and processed in real-time. The proposed algorithm is based on color histogram matching and particle filter techniques to follow the position of a musician's hands on an instrument. Data analysis enables us to determine the orientation and location of the instrument. We map these parameters to control musical performance parameters of the WF-4RIV, such as sound vibrato and sound volume. A set of experiments were proposed to verify the effectiveness of the proposed tracking system during interaction with a human player. We conclude, that the quality of the musical performance of the WF-4RIV and its capabilities to interact with musical partners, have been significantly improved by the implementation of the techniques, that are proposed in this paper.

Up to now, different kinds of musical performance robots have been developed. MPRs are designed to closely reproduce the human organs involved during the playing of musical instruments. Our research on the Waseda Flutist Robot has been focused on clarifying the human motor control from an engineering point of view. As a result, the Waseda Flutist Robot No. 4 Refined W (WF-4RIV) is able of playing the flute nearly similar to an intermediate player. Thanks to the human-like design and the advanced technical skills displayed by the WF-4RIV, novel ways of musical education can be conceived. In this paper; the General Transfer Skill System (GTSS) is implemented on the flutist robot, towards enabling the automated transfer of technical skills from the robot to flutist beginners. A set of experiments are carried out to verify the evaluation and interaction modules of the GTSS. From the experimental results, the robot is able of quantitatively evaluating the performance of beginners, and automatically recognizing the melodies performed by them.

This paper describes a static disturbance compensation control for a biped walking vehicle. To measure forces and moments caused by a passenger's motion, we use a 6-axis force/torque sensor placed under the passenger's seat. When small external force acts on a robot, only a reference ZMP trajectory is changed inside a support polygon. When large external force over a predetermined threshold force acts on a robot, a waist motion is changed. With only the proposed control, however, a robot cannot adapt to rapid disturbance changes. But we have already developed a dynamic disturbance compensation control, so by combining two controls, a human-carrying biped robot, Waseda Leg - No. 16 Refined V (WL-16RV) realized a stable dynamic walk under unknown external disturbances caused by passenger's static and dynamic motion. We confirmed the effectiveness of our proposal through experiments.

The humanoid bipedal robot WABIAN-2R was developed to be used as human motion simulator. It is able to perform similar human-like walking motion. Moreover, the robot is able to perform walking motions with a walking support device. This walking device was moving passively helping the robot to move easily. However, to go further with this development, we have to test the robot using the walking device with different conditions such as activating its wheel motors. Conducting this experiment is expected to be highly risky and costly. Therefore, we had developed a dynamic simulator in order to test the performance of the robot using the walking support device before conducting it in real simulation. © 2008 IEEE.

The humanoid bipedal robot WABIAN-2R was developed to be used as human motion simulator. It is able to perform similar human-like walking motion. Moreover, the robot is able to perform walking motions with a walking support device. This walking device was moving passively helping the robot to move easily. However, to go further with this development, we have to test the robot using the walking device with different conditions such as activating its wheel motors. Conducting this experiment is expected to be highly risky and costly. Therefore, we had developed a dynamic simulator in order to test the performance of the robot using the walking support device before conducting it in real simulation. © 2008 IEEE.

Minimally invasive surgery (MIS) has become very common in recent years, thanks to the many advantages it provides for patients. Since it is difficult for surgeons to learn and master this technique, several training methods and metrics have been proposed, both to improve the surgeon's abilities and also to assess his/her skills. This paper presents the use of the WB-1R (Waseda Bioinstrumentation system no.1. Refined), which was developed at Waseda University, Tokyo, to investigate and analyze a surgeon's movements and performance. Specifically, the system can measure the movements of the head, the arms, and the hands, as well as several physiological parameters. In this paper we present our experiment to evaluate a surgeon's ability to handle surgical instruments and his/her depth perception using a laparoscopic view. Our preliminary analysis of a subset of the acquired data (i.e. comfort of the subjects
the amount of time it took o complete each exercise
and respiration) clearly shows that the expert surgeon and the group of medical students perform very differently. Therefore, WB-1R (or, better, a newer version tailored specifically for use in the operating room) could provide important additional information to help assess the experience and performance of surgeons, thus leading to the development of a Global Performance Index for surgeons during MIS. These analyses and modeling, moreover, are an important step towards the automatization and the robotic assistance of the surgical gesture. ©2007 IEEE.

This paper proposes the mechanism and control of the biped humanoid robots WABIAN-RIV and WL-16. WABIAN-RIV has 43 mechanical degrees of freedom (d.f.): 6 d.f. in each leg, 7 d.f. in each arm, 3 d.f. in each hand, 2 d.f. in each eye, 4 d.f. in the neck and 3 d.f. in the waist. Its height is about 1.89 m and its total weight is 127 kg. It has a vision system and a voice recognition system to mimic some of the capabilities of the human senses. WL-16 consists of a pelvis and two legs having six 1 d.f. active linear actuators. An aluminium chair is mounted on two sets of its telescopic poles. To reduce the large support forces during the support phase, a support torque reduction mechanism is developed, which is composed of two compression gas springs with different stiffness. For the stability of the robots, a compensatory motion control algorithm is developed. This control compensates for moments generated by the motion of the lower limbs, using the motion of the trunk and the waist that is obtained by the zero moment point concept and fast Fourier transform. WABIAN-RIV is able to walk forwards, backwards and sideways, dance, carry heavy goods and express emotion, etc.WL-16 can move forwards, backwards and sideways while carrying an adult weighing up to 60 kg.

Airway management is provided by emergency medical technicians or anesthetists in order to save unconscious patients who are unable to breathe. Even though it is a basic technique, many accidents may occur when the procedure is not provided followed. In order to avoid any risks to patients, emergency medical technicians are required to practice airway management using training devices such as mannequins; which are designed to accurately reproduce the human anatomy. However, such training devices do not provide any quantitative information about the learning progress of trainees (passive training). For that purpose, we have proposed the development of a Airway Management Training System which is designed to embed array of sensors so that quantitative information of trainees' performance can be acquired. In this paper, we are presenting the Waseda-KyotoKagaku Airway No. 1 (WKA-1). The WKA-1 consists of three different kinds of array of sensors which are embedded into a conventional mannequin. In order to embed the array of sensors, we have simplified the design of some of the simulated organs (upper airway, oral cavity, tongue and teeth) of the mannequin. A set of evaluation parameters were proposed based on the information collected through the sensors. A set of experiments were proposed to experimentally verify the effectiveness of the proposed evaluation parameters to quantitatively detect differences among different levels of skills (anesthetists and unskilled persons).

We have developed a new three-dimensional talking robot Waseda Talker No. 6 (WT-6), which generates speech sounds by mechanically simulating articulatory motions as well as aero-acoustic phenomena in the vocal tract. WT-6 has 17-DOF vocal mechanism. It has three-dimensional lips, tongue, jaw and velum which form the 3D vocal tract structure. It also has an independent jaw opening/closing mechanism, which controls the relative tongue position in the vocal tract as well as the oral opening. The previous robot in the series had a 2D tongue and was not able to realize precise closure to produce human-like consonants such as /s/ or /r/. The new tongue, which can be controlled to form 3D shapes, is able to produce more realistic vocal tract shapes. The vocal cord model was also improved by adding a new pitch control mechanism that pushes from the side of the vocal cords. The pitch range is broader than that of the previous robot; it is sufficiently broad so as to be able to reproduce normal human speech. Preliminary experimental results showed improved synthesized speech quality for the vowels /a/, /u/ and /o/.

Personal Robots and Robot Technology (RT)-based assistive devices are expected to play a major role in Japan's elderly-dominated society, both for joint activities with their human partners and for participation in community life. These new devices should be capable of smooth and natural adaptation and interaction with their human partners and the environment, should be able to communicate naturally with humans, and should never have a negative effect on their human partners, neither physical nor emotional. To achieve this smooth and natural integration between humans and robots, we need first to investigate and clarify how these interactions are carried out. Therefore, we developed the portable Bioinstrumentation System WB-IR (Waseda Bioinstrumentation system no.1 Refined), which can measure the movements of the head, the arms, the hands (position, velocity, and acceleration), as well as several physiological parameters (electrocardiogram, respiration, perspiration, pulse wave, and so on), to objectively measure and understand the physical and physiological effects of the interaction between robots and humans. In this paper we present our development of the head and hands motion capture systems as additional modules for the Waseda Bioinstrumentation system No.1 (WB-1). The preliminary experimental results, given the inexpensiveness of the systems, are good for our purposes.

Personal robots and Robot Technology (based assistive devices are expected to play a major role in Japan's elderly dominated society, both for joint activities with their human partners and for participation in community life. These new devices should be capable of smooth and natural adaptation and interaction with their human partners and the environment, should be able to communicate naturally with humans, and should never have a negative effect on their human partners, neither physical nor emotional. To achieve this smooth and natural integration between humans and robots, we need first to investigate and clarify how these interactions are carried out.
Therefore, we developed the portable Bioinstrumentation System WB-2 (Waseda Bioinstrumentation system No.2), which can measure the movements of the head, the arms, and the hands (position, velocity, and acceleration), as well as several physiological parameters (electrical activity of the heart respiration, perspiration, pulse wave, and so on), to objectively measure and understand the physical and physiological effects of the interaction between robots and humans. In this paper we present our development of the Inertial Measurement Unit, which is at the heart of our new motion-capture system that replaces the system used in the Waseda Bioinstrumentation system No.1 Refined (WB-1R). Some preliminary results of experiments with the unit are also presented and analyzed.

Up to now, there is no scientific methodology for the assessment of surgical skills during the training progress. Nowadays, an objective structured clinical examination (OSCE) has been proposed as a modern type of examination often used in medicine to test skills such as communication, clinical examination, medical procedures, etc. The assessment of skills is realized by practical exams, in which students are evaluated by experienced examiner using a check list. However, this approach highly depends on the examiner's criteria. In fact, the examiner lacks of information to objectively evaluate trainees' performance (which cannot be obtained trough the simple observation of the task). For that purpose, we have proposed the development of a suture/ligature training system which provides quantitative information of the movement of an artificial skin as well as information of the quality of the suture. Such information is provided by means of the (W) under bar aseda-(K) under bar yotoKagaku (S) under bar uture No.(2) under bar Refined (WKS-2R) which has been developed by the authors. In this paper, the evaluation parameters proposed for the assessment of the sutture/ligature task are detailed. Such evaluation parameters were proposed based on the functionalities of the WKS-2R and our studies of the OSCE examination. Preliminary experiments were carried out to analyze the performance of trainees while performing the suture/ligature task with the WKS-2R;L From the experimental results, we could collect information from the seven proposed evaluation parameters and analyze their behavior.

Airway management is provided by emergency medical technicians or anesthetists in order to save unconscious patients under emergency situations. Even though airway management is basic skill, there may be some difficulties while performing airway management to patients with abnormalities. Therefore, it is important to train medical students to perform such a task on patients with abnormalities. Recently, many companies are developing airway training mannequins designed to reproduce the conditions of the airway management procedure. However, such training devices cannot provide any quantitative information of the training progress so that few amount of feedback can be provided to trainees. For this purpose, we have proposed the development of an airway management training system which has been designed to embed sensors into a conventional mannequin. As a result, we have developed the (W) under bar aseda-(K) under bar yotokagaku (A) under bar irway No. (1) under bar (WKA-1). In this paper, the WKA-1 was used to reproduce the airway management on patients with abnormalities on jaw opening. For this purpose, we have added an array of springs to simulate those abnormalities. Then, we proposed an experiment to detect the differences on performances among doctors (anesthetist) while performing the airway management in patients with and without abnormalities on the jaw opening. Both cases were analyzed quantitatively by using the functionalities of the WKA-1. From the experimental results, we could find a statistically significant difference between both cases.

Authors have proposed as a long-term goal, since 2004, the development of a patient robot which could serve for both training purposes as well as an evaluation tool of medical procedures. As a first approach, we have developed last year a suture and ligature training system named Waseda Kyotokagaku Suture No. 1 (WKS-1), which is composed by a K commercial skin dummy with arrays of embedded sensors designed to acquire quantitative data of the task. The WKS-1 was designed to reproduce realistically the task conditions as well as providing objective assessment of the task performance. In particular, the proposed evaluation function considered the following performance indexes: time, displacement and force levels. By performing experiments with medical doctors and unskilled persons, we confirmed the effectiveness of WKS-1 to provide objective assessments of the task performance. However, the functionalities of WKS-1 were too restricted as few automatic procedures were implemented for the acquisition and processing of the collected data. Therefore; in this paper, Kyotokagaku Suture No. 2 we are presenting the Waseda K (WKS-2). The WKS-2 has been designed to provide more detailed information of the task performance as well as improving its portability, connectivity, and usability. In addition, thanks to the design improvements on the WKS-2, we have proposed additional evaluation parameters to measure the quality of the suture (after the task has been completed). For this purpose, we proposed a image processing algorithm to automatically measure the width of sutures, the distance among them and the wound area. Preliminary experiments were carried out to verify its effectiveness.

Surgeons, during a medical intervention, perform different kinds of manual tasks with dexterity and precision. In order to assure the success of the intervention, medical students are trained several years using training models so that they can perform such tasks with accuracy to avoid any possible risk to patients. However, current training models are merely designed to imitate the surgical procedure without providing any further information about the how well the task was done. For that reason; in this paper, the development of a Suture/Ligature Training System is proposed to imitate surgical procedures as well as provide quantitative information of the learning progress of trainees. As a first approach, a training system was designed to simulate the suture and ligature tasks. The proposed training system includes a skin dummy with an array of embedded photo interrupters to detect the movement of the skin dummy; without requiring any modification on the surgical instrument. In this paper, different task parameters were proposed to understand trainees' learning progress and different experiments were carried out to identify the evaluation parameters that may provide useful information about how well the task was performed. As a result from the experiments, the evaluation parameters for the suture and ligature were determined. Finally, an evaluation function was proposed and further experiments were proposed to verify its effectiveness. From the results of the experiments, we could effectively distinguish quantitatively the differences of skill levels between surgeons and unskilled persons as well as identifying the learning progress of trainees by plotting the learning curve.

Experiments on animals has been playing very important part in psychology, medical science, genetics and brain science. Rodents are one of the most popular experimental subjects in these experiments. In psychology and brain science, behavior test and analysis on rodents, especially rats, has been performed to clarify mechanisms of mind or brain functions. "Open-field test" is one of the most popular research methods to investigate their behavior. In the "open-field test," rats are released into the "open-field," circle or square, flat arena surrounded by walls, and their behavior parameters such as position, moving distance, number of grooming and rearing are measured. With conventional experimental setups, these parameters has been measured and recorded by humans. Observing and recording are heavy task for experimenters, and also involves some human errors and subjectivity. Therefore, we developed an autonomous experimental setup which measures rats' position, number of grooming and rearing in the open-field. In addition, an active tracking camera which takes high resolution images of the rat in the open-field was developed. To prevent losing tracks of the rat, a prediction model of rat's movement is developed and integrated into the control of this camera.

It is well known that the massage therapy is useful for the rehabilitation of various diseases. Although various apparatus have been developed for the massage of the torso and limbs, a machine to perform precise massage therapy to maxillofacial region is not developed yet. Therefore, we developed a robot system that provides massage therapy to maxillofacial region. The name of our newly developed robot was WAO-1. WAO-1 has been designed to perform appropriate massage to the patients with dry mouth, etc. WAO-1 is composed by two 6-degree of freedom arms with plungers attached at the end-effectors. The massage is applied to the patient by controlling the force and position of the plunger (virtual compliance). As a preliminary step of the clinical application, a simulation therapy of robotic massage to stimulate salivary flow from parotid gland was performed. The dynamic force on patient's head during the massage using WAO-1 was evaluated. The results suggested that WAO-1 could perform equivalent massage to human hand. We expect that WAO-1 will be useful to provide massage therapy to several patients with oral health problems. This will aim in reducing the therapy costs due to the need of human efforts when long-time therapies are needed.

This paper describes how to compensate unknown external forces caused by a rider's motion of a biped walking vehicle. When external forces act on a robot's waist, the waist is accelerated so that a measured ZMP may be equal to a reference ZMP. To inhibit the divergence of the waist motion, the reference ZMP is varied inside a support polygon. However, if a large external force acts on a robot, the waist trajectory does not converge by only controlling a reference ZMP. So, ZMP trajectory is varied by changing a foot-landing point. Using the proposed control method, WL-16RIV (Waseda Leg - No.16 Refined IV) achieved a stable human-carrying walking under unknown external forces which exert forward and sideways on the robot's waist. Through various walking experiments, the effectiveness of the proposed method was confirmed.

Previously, the realization of ascending and descending stairs and landing pattern modification control by WL-16RII were reported. However, it is difficult to use the landing pattern modification control when ascending stairs, because of the insufficient stroke of linear actuators. In this report, the design of a double stage linear actuator with a larger expansion and contraction ratio is described. The new linear actuators developed have been installed in WL-16RII, and several experiments were conducted. Through experiments involving walking with a wide step length and ascending a stair with landing pattern modification control, the effectiveness of the actuator developed is confirmed.

Many control methods have been studied on the assumption that the feet of biped robots contact the ground with four points. However, it is difficult for almost all of such biped robots to maintain four-point contact on uneven terrains because they have rigid and flat soles. In order to solve the problem, foot mechanisms should be studied. In 2003, we developed WS-1R (Waseda Shoes - No.1 Refined) which is able to maintain four-point contact. However, it is difficult to deal with the concave or convex ground because of the problems of the contact detection and sideways slip. So, WS-5 (Waseda Shoes - No.5) has been developed. To avoid the slip of the foot, a cam-slider locking system consisting of a solenoid and a cam is constructed and installed at the foot. Also, linear encoders are employed to measure the position of the foot sliders. Through walking experiments on uneven terrains, the effectiveness of WS-5 is confirmed.

Up to now, there is no scientific methodology for the assessment of surgical skills during the training progress. Nowadays, an objective structured clinical examination (OSCE) has been proposed as a modern type of examination often used in medicine to test skills such as communication, clinical examination, medical procedures, etc. The assessment of skills is realized by practical exams, in which students are evaluated by experienced examiner using a check list. However, this approach highly depends on the examiner's criteria. In fact, the examiner lacks of information to objectively evaluate trainees' performance (which cannot be obtained trough the simple observation of the task). For that purpose, we have proposed the development of a suture/ligature training system which provides quantitative information of the movement of an artificial skin as well as information of the quality of the suture. Such information is provided by means of the (W) under bar aseda-(K) under bar yotoKagaku (S) under bar uture No.(2) under bar Refined (WKS-2R) which has been developed by the authors. In this paper, the evaluation parameters proposed for the assessment of the sutture/ligature task are detailed. Such evaluation parameters were proposed based on the functionalities of the WKS-2R and our studies of the OSCE examination. Preliminary experiments were carried out to analyze the performance of trainees while performing the suture/ligature task with the WKS-2R;L From the experimental results, we could collect information from the seven proposed evaluation parameters and analyze their behavior.

Airway management is provided by emergency medical technicians or anesthetists in order to save unconscious patients under emergency situations. Even though airway management is basic skill, there may be some difficulties while performing airway management to patients with abnormalities. Therefore, it is important to train medical students to perform such a task on patients with abnormalities. Recently, many companies are developing airway training mannequins designed to reproduce the conditions of the airway management procedure. However, such training devices cannot provide any quantitative information of the training progress so that few amount of feedback can be provided to trainees. For this purpose, we have proposed the development of an airway management training system which has been designed to embed sensors into a conventional mannequin. As a result, we have developed the (W) under bar aseda-(K) under bar yotokagaku (A) under bar irway No. (1) under bar (WKA-1). In this paper, the WKA-1 was used to reproduce the airway management on patients with abnormalities on jaw opening. For this purpose, we have added an array of springs to simulate those abnormalities. Then, we proposed an experiment to detect the differences on performances among doctors (anesthetist) while performing the airway management in patients with and without abnormalities on the jaw opening. Both cases were analyzed quantitatively by using the functionalities of the WKA-1. From the experimental results, we could find a statistically significant difference between both cases.

Authors have proposed as a long-term goal, since 2004, the development of a patient robot which could serve for both training purposes as well as an evaluation tool of medical procedures. As a first approach, we have developed last year a suture and ligature training system named Waseda Kyotokagaku Suture No. 1 (WKS-1), which is composed by a K commercial skin dummy with arrays of embedded sensors designed to acquire quantitative data of the task. The WKS-1 was designed to reproduce realistically the task conditions as well as providing objective assessment of the task performance. In particular, the proposed evaluation function considered the following performance indexes: time, displacement and force levels. By performing experiments with medical doctors and unskilled persons, we confirmed the effectiveness of WKS-1 to provide objective assessments of the task performance. However, the functionalities of WKS-1 were too restricted as few automatic procedures were implemented for the acquisition and processing of the collected data. Therefore; in this paper, Kyotokagaku Suture No. 2 we are presenting the Waseda K (WKS-2). The WKS-2 has been designed to provide more detailed information of the task performance as well as improving its portability, connectivity, and usability. In addition, thanks to the design improvements on the WKS-2, we have proposed additional evaluation parameters to measure the quality of the suture (after the task has been completed). For this purpose, we proposed a image processing algorithm to automatically measure the width of sutures, the distance among them and the wound area. Preliminary experiments were carried out to verify its effectiveness.

It is well known that the massage therapy is useful for the rehabilitation of various diseases. Although various apparatus have been developed for the massage of the torso and limbs, a machine to perform precise massage therapy to maxillofacial region is not developed yet. Therefore, we developed a robot system that provides massage therapy to maxillofacial region. The name of our newly developed robot was WAO-1. WAO-1 has been designed to perform appropriate massage to the patients with dry mouth, etc. WAO-1 is composed by two 6-degree of freedom arms with plungers attached at the end-effectors. The massage is applied to the patient by controlling the force and position of the plunger (virtual compliance). As a preliminary step of the clinical application, a simulation therapy of robotic massage to stimulate salivary flow from parotid gland was performed. The dynamic force on patient's head during the massage using WAO-1 was evaluated. The results suggested that WAO-1 could perform equivalent massage to human hand. We expect that WAO-1 will be useful to provide massage therapy to several patients with oral health problems. This will aim in reducing the therapy costs due to the need of human efforts when long-time therapies are needed.

Experiments on animals has been playing very important part in psychology, medical science, genetics and brain science. Rodents are one of the most popular experimental subjects in these experiments. In psychology and brain science, behavior test and analysis on rodents, especially rats, has been performed to clarify mechanisms of mind or brain functions. "Open-field test" is one of the most popular research methods to investigate their behavior. In the "open-field test," rats are released into the "open-field," circle or square, flat arena surrounded by walls, and their behavior parameters such as position, moving distance, number of grooming and rearing are measured. With conventional experimental setups, these parameters has been measured and recorded by humans. Observing and recording are heavy task for experimenters, and also involves some human errors and subjectivity. Therefore, we developed an autonomous experimental setup which measures rats' position, number of grooming and rearing in the open-field. In addition, an active tracking camera which takes high resolution images of the rat in the open-field was developed. To prevent losing tracks of the rat, a prediction model of rat's movement is developed and integrated into the control of this camera.

In this paper, the methodology for automatically generating an expressive performance on the anthropomorphic flutist robot is detailed. A feed-forward network trained with the error back-propagation algorithm was implemented to model the performance's expressiveness of a professional flutist. In particular, the note duration and vibrato were considered as performance rules (sources of variation) to enhance the robot's performance expressiveness. From the mechanical point of view, the vibrato and lung systems were re-designed to effectively control the proposed music performance rules. An experimental setup was proposed to verify the effectiveness of generating a new score with expressiveness from a model created based on the performance of a professional flutist. As a result, the flutist robot was able of automatically producing an expressive performance similar to the human one from a nominal score.

The research on the anthropomorphic flutist robot, at Waseda University, has focused on clarifying the human motor control while playing the flute, proposing novel applications for humanoid robots and enabling the communication with humans at the emotional level. As a result of our research, the flutist robot is able of nearly reproducing the basic technical skills required to play the flute. Furthermore, some of the extended technical skills have been roughly simulated by the robot. However, in order to enhance the expressiveness of the robot's performance, still further improvements are required. In particular, in this paper, we focus our research on understanding better how to enhance the expressiveness of the flute performance by studying in more detail the vibrato, which is believe to be one of the most important ways of expressing feelings/ideas while performing the flute. For this reason, the newest version of the flutist robot, the Waseda Flutist Robot No.4 Refined III has been developed by focusing on improving the design of the lung and designing of a human-like vocal cord mechanism, which are believed to have a close relation in producing vibrato. The details of the new mechanism are given and experiments were conducted to understand the effect of the movement of diaphragm and glottis while producing vibrato.

Our research on the anthropomorphic flutist robot has been focused on understanding the human motor control, enabling the communication between human and robots, proposing novel applications for humanoid robots and introducing novel ways of musical expression. In this video, we are presenting the musical skills of the Waseda Flutist Robot. In particular, we are presenting the WF-4RIV; which is able of performing musical performances requiring basic as well as extended technical skills. Thanks to the most recent mechanical improvements, the WF-4RIV is able of performing musical scores that are commonly part of the repertoire of intermediate level players. In this video, we are presenting the WF-4RIV performing the Flight of the Bumble Bee, Le Cygne and Trois Duos de Mendelssohn et Lachner.

As a result from our research, the Waseda Flutist Robot is able of playing the flute nearly similar to an intermediate level flutist. In order to enhance the expressiveness of its performance, we are focusing our research on improving the mechanical design of the simulated organs as well as implementing automated algorithms for the generation of expressive music performance. In a previous research, we have developed a human-like vocal cord to improve the production of vibrato. In this paper, we are presenting the newest version of the flutist robot; where the lips, oral cavity and tonguing mechanisms were improved. Such improvements were proposed to effectively control the attack time and double tonguing. The attack time is useful to produce clear sounds and the double tonguing is an important articulation that helps players to produce shaped notes and smooth transitions between notes. The lips mechanism is composed by 3-DOFs which enables the accurate control of the air stream parameters (width, thickness and angle). The lips of the robot were designed more human-like by using a thermoplastic rubber (septon). The oral cavitywas designed similar to the human one also made by septon. Inside the oral cavity, an improved tonguing mechanism was designed (1-DOF) to reproduce better the double tonguing technique. A set of experiments were performed to analyze the improvements on the dynamical properties of the sound while playing the flute.

It is well known that the massage therapy is useful for the rehabilitation of various diseases. Although various apparatus have been developed for the massage of the torso and limbs, a machine to perform precise massage therapy to maxillofacial region is not developed yet. Therefore, we developed a robot system that provides massage therapy to maxillofacial region. The name of our newly developed robot was WAO-1. WAO-1 has been designed to perform appropriate massage to the patients with dry mouth, etc. WAO-1 is composed by two 6-degree of freedom arms with plungers attached at the end-effectors. The massage is applied to the patient by controlling the force and position of the plunger (virtual compliance). As a preliminary step of the clinical application, a simulation therapy of robotic massage to stimulate salivary flow from parotid gland was performed. The dynamic force on patient's head during the massage using WAO-1 was evaluated. The results suggested that WAO-1 could perform equivalent massage to human hand. We expect that WAO-1 will be useful to provide massage therapy to several patients with oral health problems. This will aim in reducing the therapy costs due to the need of human efforts when long-time therapies are needed.

This paper describes how to compensate unknown external forces caused by a rider's motion of a biped walking vehicle. When external forces act on a robot's waist, the waist is accelerated so that a measured ZMP may be equal to a reference ZMP. To inhibit the divergence of the waist motion, the reference ZMP is varied inside a support polygon. However, if a large external force acts on a robot, the waist trajectory does not converge by only controlling a reference ZMP. So, ZMP trajectory is varied by changing a foot-landing point. Using the proposed control method, WL-16RIV (Waseda Leg - No.16 Refined IV) achieved a stable human-carrying walking under unknown external forces which exert forward and sideways on the robot's waist. Through various walking experiments, the effectiveness of the proposed method was confirmed.

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The development of the flutist robot at Waseda University since 1990 has enabled a better understanding of the motor control functions required for playing the flute. Moreover, it has introduced novel ways of interaction between human beings and humanoid robots such as: performing a musical score together in real time and transferring skills to flutist beginners. In this paper, the development of the Waseda Flutist Robot No. 4 Refined (WF-4R) is presented. The mechanical design of the components of the robot and the control architecture are detailed. In order to efficiently control and coordinate the motion of each of the simulated organs of the robot, an algorithm was proposed to extract the features required to perform a score based on human performance. This algorithm was divided into two phases: sound calibration and music score performance. Finally, an experimental setup was done to verify the effectiveness of each of the phases by analyzing the time and frequency domain responses from recordings of the robot performances. The WF-4R is able to perform from musical scores quite similar to human.

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（フルペーパ査読）

（フルペーパ査読）

（フルペーパ査読）

（フルペーパ査読）

The development of the anthropomorphic flutist robot, at Waseda University, has focused on imitating the human flute playing by mechanically reproducing the organs involved during such activity. Our research aims in understanding several aspects of the human flute playing: clarifying the human motor control while performing skillful activities, enabling robots to express ideas and feelings in musical terms and proposing new ways of interaction between the human and the robot. In this paper the new version of the flutist robot, the Waseda Flutist Robot No. 4 Refined II, is presented. The improvements of the mechanical system in order to improve the sound clarity of the robot's performance and to enhance the interaction with humans are described. A set of experiments were carried out to verify the effectiveness of the mechanical components. As a result, the robot is able of performing a musical score with more clarity and furthermore, the robot can interact with humans more natural using the vision system.

A humanoid robot, WABIAN-2R, capable of human-like walk with stretched knees and heel-contact and toe-off motions is proposed in this paper. WABIAN-2R has two 1-DOF passive joints in its feet to enable it to bend its toes in steady walking. Further, it has two 6-DOF legs, a 2-DOF pelvis, a 2-DOF trunk, two 7-DOF arms with 3-DOF hands, and a 3-DOF neck. In addition, a new algorithm for generating walking patterns with stretched knees and heel contact and toe-off motions based on the ZMP criterion is described. In this pattern generation, some parameters of the foot trajectories of a biped robot are optimized by using a genetic algorithm in order to generate a continuous and smooth leg motion. Software simulations and walking experiments are conducted, and the effectiveness of the pattern generation and mechanism of WABIAN-2R, which have the ability to realize more human-like walking styles in a humanoid robot, are confirmed.

A new humanoid robot-WABIAN-2-that can be used as a human motion simulator is proposed in this paper. Its trunk is designed in order to permit rotation, and forward, backward, and sideway movement. Further, its arms are designed to support its complete weight when pushing a walk-assist machine. Moreover, it can lean on a walk-assist machine by forearm control using trunk motion. Basic walking experiments with WABLAN-2 are conducted with and without a walk-assist machine, thereby confirming its effectiveness.

We developed a sensor feedback mechanism for an anthropomorphic talking robot WT-5 (Waseda Talker No. 5). In human speech, sensory feedback is more important when we producing obstacle consonant sounds, such as /t/ and /d/, compared to the auditory feedback mechanism. We reproduce this mechanism by placing tactile sensors and a pressure sensor on the palate of a talking robot and reducing the error between the pressure of the human voice and the robot consonant production. In addition, we developed more efficient optimization methods than those of WT-4, using speech recognition and the pre-optimized memory of vowels. Using these mechanisms, we realized continuous mimic speaking that includes consonant sounds.

A new humanoid robot-WABIAN-2that can be used as a human motion simulator is proposed in this paper. Its trunk is designed in order to permit rotation, and forward, backward, and sideway movement. Further, its arms are designed to support its complete weight when pushing a walk-assist machine. Moreover, it can lean on a walk-assist machine by forearm control using trunk motion. Basic walking experiments with WABIAN-2 are conducted with and without a walk-assist machine, thereby confirming its effectiveness.

To establish an integrated evaluation system for a clinical surgeon and a surgical robot, our group has been proposed a new concept; a "Patient Robot", which is a sort of in vitro mock circulatory system that provides various types of coronary disease as a training machine for cardiac surgeons. The development of "Patient Robot" has been done by a following procedure, 1) Measurements, 2) Modelling, 3) In-vitro Simulation and 4) Evaluation. This paper focused on the rolls of 2) Modelling and 3) Simulation. As the modelling phase, Coronary artery and Graft vessels have been modelled by silicone ruber with an instruction by senior cardiac surgeons' sensitive tactual feeling through their interview. As a result of the interview and tensile test of the silicone vascular models, a favourable range of Young's modulus has been identified, which was &lt; 0.1 N/mm(2) (where epsilon=1.0). As for the Simulation phase, the silicone vascular models have been mounted on Coronary Circulation System, which is named "Scoring System". A waveform of blood flow has been obtained by using the "Scoring System" with the silicone vascular models. The waveform was similar to native coronary arterial blood flow. Also, it has been found that coronary arterial blood flow rate is adjustable by controlling the input of the heart rate to the Scoring System. As a conclusion, it has been expressed that it is possible to create a virtual surgical environment which is Able to be controlled quantitatively.

The walking biped robot (WABIAN-2LL) can imitate human motions such as knee-stretching locomotions and deep bending motions because it is designed with large movable ranges as a human. It has two seven degrees of freedom (DOF) legs and a two DOF waist. Each leg consists of a three DOF ankle, a one DOF knee and a three DOF hip to deal with human walking motion. Its height is about 1.2[m], and its weight is 40[kg]. Also, how to make a knee-stretched walk pattern is proposed. During the walking, moments generated by the motion of the legs should be cancelled. So, a compensatory motion control algorithm is used which is based on the waist motion. Through dynamic walking experiments, the effectiveness of the biped robot is confirmed.

In this paper, the main improvements of the mechanical, perceptual and performance control systems, implemented on the Waseda Flutist Robot No.4 Refined H, are presented. Each of the systems of the flutist robot has been designed in order to imitate as near as possible the skills displayed by human during the flute performance; as a mean for clarifying the internal processes of the human motor control to perform skillful activities, enabling the robot to express ideas/feetings in musical terms, and proposing new ways of interaction between the human and the robot. A set of experiments were proposed to verify the effectiveness of the perceptual system as wells as the proposed volume control algorithm implemented on this robot. As a result, the robot has demonstrated to be able of recognizing automatically melodies from the performance of flutist beginners, detecting and tracking the presence of a human face and performing with more expressiveness by controlling the sound volume.

In this paper, a humanoid robot named as WABIAN-RIV (WAseda BIpedal humANoid Retined IV) is analyzed in terms of stiffness characteristics. This paper proposes basic models and a formulation in order to deduce the stiffness matrix as a function of the most important stiffness parameters of the WABIAN architecture. The proposed formulation is useful for numerical estimation of stiffness performances. An evaluation of stiffness performances is carried out by numerically implementing the proposed formulation. An experimental validation of the numerical results is also carried out on WABIAN-RIV humanoid robot. (c) 2005 Elsevier Ltd. All rights reserved.

We propose a new robot actuator, especially a robot actuator gear which has a very effective feature of backdrivability. We show the study of the new definition of backdrivability of an actuator gear which has the quantitative definition. From this definition we propose the method of making the gear which has a good backdrivability. Based on this method, the actuator gear was developed and we show the result from the experiment. The comparisons with the other types of actuator gear which are Harmonic drive gear and normal planetary gear are described. Finally the comparison has proved that the developed actuator gear has very effective backdrivability.

A new humanoid robot capable of various motions is proposed in this paper, which has a 2-DOF pelvis and 2-DOF trunk. A new upper body mechanism is mounted on a leg machine, WABIAN2/LL, and a full scale humanoid robot, WABIAN-2, is constructed in this study. Its trunk is designed to bend forwards, backwards and sideways and rotate in combination with a 2-DOF pelvis. Also, the upper body is designed in way that makes it able to use a walk-assist machine. Basic walking experiments with and without a walk-assist machine are conducted, and the effectiveness of the mechanism of WABIAN-2 is confirmed.

We developed an anthropomorphic talking robot WT5 (Waseda Talker No. 5) having a sensor feedback mechanism and novel vocal cords based on human biological structures. The sensory feedback Is more Important when we producing obstacle consonant sounds, compared to the auditory feedback mechanism. We reproduce this mechanism by placing tactile sensors and a pressure sensor on the palate of a talking robot and reducing the error between the pressure of the human voice and the robot consonant production. The vocal cord model was constructed with a similar structure to the biological structure of the human vocal cords and vibrated like those of a human. In addition, using these mechanisms, WT-5 could produce voices closer to those of a human. And also realized continuous mimic speaking that Includes consonant sounds.

A Personal Robot is expected to become popular in the future. It is required to be active in joint work and community life with humans. Therefore, we have been developing new mechanisms and functions for a humanoid robot that can express emotions and communicate naturally with humans. In this paper, we present the mechanical design of the Emotion Expression Humanoid Robot WE-4RII, which was developed by integrating the Humanoid Robot Hands RCH-1 into the previous version WE-4R*. The robot has four of the five human senses for detecting external stimuli: visual, tactile, auditory and olfactory, and 59-DOFs for expressing motion and emotions. It is capable of expressing seven basic emotional patterns.

Personal robots, which are expected to become popular in the future, are required to be active in joint work and community life with humans. Such robots must have no bad physical or psychical effect on humans. The psychical effect of a robot on humans has been subjectively measured using questionnaires. However, it has not been objectively measured yet. Human emotion and the consciousness direction can be measured by physiological parameters and body motion, respectively. Therefore, the bioinstrumentation system WB-1 was developed in order to objectively measure the psychical effect of a robot on a human. It can measure physiological parameters such as respiration, heart rate, perspiration and pulse wave, and arm motion. Analyzing human stress in the interaction with a robot from electrocardiogram, the robot could generate a motion for decreasing the stress.

Your Face is one of the most important factors in communicating with people. At present, the TV-phone, which can transmit Face information, is becoming a part of modern life. In order to transfer more realistic Face information, we propose the face shape robot WD-1 (W) under bar aseda-(D) under bar ocomo face robot No.(1) under bar, which can express various face shapes by morphing an average mask (made of SEPTON) through 19 facial control-points. In this study, an average face mask is made in order to express a wide range of shapes with few control points. The position, number and movement range of the control-points are optimized. In addition, we introduce 3-DOFs drive units and control each control-point on a plane, not at a point. In order to evaluate the performance of WD-1, we measure the shape error between the faces of three subjects and the WD-1 equivalents. We elucidate the weaknesses of the current WD-1 implementation: a paucity of control points on the face line and wrinkling of the mask due to excessive local stress.

Personal robots, which are expected to become popular in the future, are required to be active in joint work and community life with human. Therefore, the objective of this study is the development of new mechanisms and functions for a humanoid robot to express emotions and to communicate naturally with human. We developed both the mental model front psychological point of view and the Emotion Expression Humanoid Robot WE-4RII (Waseda Eye No.4 Refined 11) from engineered point of view.In this paper, a co-associative memory model using mutually coupled chaotic neural networks was proposed and implemented ill WE-4RII as its mental model. We confirmed that the robot could generate the behavior depending on its mood ill response to a stimulus.

In a society getting older year by year, Robot technology (RT) is expected to play an important role. In order to achieve this objective, the new generation of personal robots should be capable of a natural communication with humans by expressing human-like emotion. In this sense, the hands play a fundamental role in communication, because they have grasping, sensing and emotional expression ability. This paper presents the recent results of the collaboration between the Takanishi Lab of Waseda University, Tokyo, Japan, and the Arts Lab of Scuola Superiore Sant' Anna, Pisa, Italy, and RoboCasa in a biologically-inspired approach for the development of a new humanoid hand. In particular, the grasping and gestural capabilities of the novel anthropomorphic hand for humanoid robotics RCH-1 (RoboCasa Hand No.1) are presented.

We developed an anthropomorphic talking robot WT-5 (Waseda Talker No. 5) having a sensor feedback mechanism and novel vocal cords based on human biological structures. The sensory feedback is more important when we producing obstacle consonant sounds,, compared to the auditory feedback mechanism. We reproduce this mechanism by placing tactile sensors and a pressure sensor on the palate of a talking robot and reducing the error between the pressure of the human voice and the robot consonant production. The vocal cord model was constructed with a similar structure to the biological structure of the human vocal cords and vibrated like those of a human. In addition, using these mechanisms, WT-5 could produce voices closer to those of a human. And also realized continuous mimic speaking that includes consonant sounds.

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This study has been conducted by participating in the Humanoid Robotics Project (HRP) of the METI, which aims at developing applications of humanoid robots. We consider the humanoid robot is effective in applications that covers the services to human beings such as elderly care, patient care, since it presents affinity to people owing to its human-like figure and motions. In this study, our focus was a situation in which the robot is expected to support activities of people in a hospital with three kinds of possible system users who are a nurse, a patient and a family member in the remote site. Taking the capabilities of current humanoid robots into account, we designed the user interface of the system which satisfies the requirements of the each three users to operate the robot in the assumed situation. Furthermore, we confirmed the feasibility of the designed system through experimental examples by integrating the developed user interface with a humanoid robot as a total system.

This paper describes development of a new human-like talking robot WT-4 aaseda Talker No. 4). WT-4 was developed to overcome the problems related to the lack of variation in the formant frequency of the sounds generated by the previous talking robot WT-3. These problems arose particularly on the first formant (F1) where frequencies of less than 500 [Hz] could not be reached. And the differences among WT-3's vowels were not clear; which may have been caused by the sound source of the vocal cords and the lips. Therefore, the connection between the vocal cords and the vocal tract was improved, as well as the lips mechanism. As the result of these improvements, WT-4's sounds were quite similar to a human's, and WT-4 was able to reproduce suitable sounds using auditory feedback.

The development of the anthropomorphic flutist robot, at Waseda University, has demonstrated how the robot can communicate with humans at emotional level by performing musical scores with expressiveness and by transferring basic skills from robot to beginners. However, the interaction among humans is characterized by a highly interactive process of analyzing and responding to incoming stimuli from the partner. Even that flutist robot has successfully imitated the flute playing quite similar to human performance; the way of processing and analyzing the music as human does still requires further improvements. In this paper, we will describe how we implemented a human like sound processing system to enable robot to interact with humans at the same level of perception. An experimental setup was done to verify the validity of the developed system.

One of the earliest motivations for developing humanoid robots centered on creating robots that may coexist with humans in environments created for human beings. For several years, at Waseda University, the development of the anthropomorphic flutist player has been focused on improving the musical interaction between the human and the robot to clarify the human flute playing and to propose novel assisted music teaching tools. In this paper, a new architecture for autonomously transfer skills from robot to human using the flutist robot is introduced. Furthermore, the new version of the flutist robot, the WF-4R (Waseda Flutist No.4 Refined) is presented; where the arm system was added to assure the positioning accuracy of the flute and the development of a melody recognition system to enable the robot to interact with students at the same logical level of perception. An experimental setup has been performed in order to verify the effectiveness of both mechanical and perceptual systems. As a result, using the arms system, we have assured the repetitiveness of the flute positioning. Furthermore, the implemented music recognition system was able of recognizing the melody of flutist players (an overall recognition rate of 90%); demonstrating that HMM (usually used for speech recognition) is also effective for flute melody identification.

This paper addresses a compensatory motion control algorithm of a biped robot to deal with stable dynamic walking on even or uneven terrain. This control algorithm consists of three main parts; the introduction of a virtual plane to consider ZMP (Zero Moment Point); an iteration algorithm to compute the trunk motion; and a program control to realize dynamic walking. The virtual plane is defined as a plane formed by the support points between the surface of terrain and the soles. In order to obtain the trunk motion capable of compensating for the moments produced, by the motion of the lower-limbs during the walking, ZMP equation on the virtual plane is computed by using an iteration method. Also, a walking pattern. is presented which is composed of the trajectories of lower-limbs, waist and trunk. The walking pattern is commanded to the joints of WL-12RIII (Waseda Leg-Twelve Refined Three) using a program control method. Through walking simulations and experiments on an uneven terrain, such as stairs and sloped terrain, the effectiveness of the control method is verified.

This paper describes the evaluation of three different walking patterns of a biped humanoid robot. Stretch-walking patterns with straight legs for a biped robot are compared with conventional walking patterns with bent legs in terms of energy consumption. This paper discusses walking pattern generation for various walks. To confirm the walking pattern evaluation, we have developed a biped robot, WABIAN-2/LL, whose leg mechanism differs from the conventional leg mechanism that has 3 DOF (degrees of freedom) in each ankle, 1 DOF in each knee, 3 DOF in each hip, and 2 DOF in the waist. Walking experiments are conducted with WABLA-N-2/LL, and the results demonstrate that stretch walking patterns are effective in terms of energy consumption.

The authors introduced the mental model and the Robot Personality for humanoids. The Mental Vector which expressed the mental state was denned in a 3D mental space and determined based on the Equations of Emotion. The Robot Personality consists of the Sensing Personality and Expression Personality. We implemented them to the human-like head robot WE-3RV. It could express the various mental states caused by stimuli from the environment.

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This paper describes emotion-based walking for a biped humanoid robot. In this paper, three emotions, such as happiness, sadness and anger are considered. These emotions are expressed by the walking styles of the biped humanoid robot that are preset by the parameterization of its whole body motion. To keep its balance during the emotional expressions, the motion of the trunk is employed which is calculated by the compensatory motion control based on the motions of the head, arms and legs. We have constructed a biped humanoid robot, WABIAB-RII (WAseda BIpedal humANoid robot-Revised II), to explore the issue of the emotional walking motion for a smooth and natural communication. WABIAN-RII has forty-three mechanical degrees of freedom and four passive degrees of freedom. Its height is about 1.84 m and its total weight is 127 kg. Using WABIAN-RII, three emotion expressions are experimented by the biped walking, including the body motion, and evaluated.

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This paper describes position-based impedance control for biped humanoid robot locomotion. The impedance parameters of the biped leg are adjusted in real-time according to the gait phase. In order to reduce the impact/contact forces generated between the contacting foot and the ground, the damping coefficient of the impedance of the landing foot is increased largely during the first half double support phase. In the last half double support phase, the walking pattern of the leg changed by the impedance control is returned to the desired walking pattern by using a polynomial. Also, the large stiffness of the landing leg is given to increase the momentum reduced by the viscosity of the landing leg in the first half single support phase. For the stability of the biped humanoid robot, a balance control that compensates for moments generated by the biped locomotion is employed during a whole walking cycle. For the confirmation of the impedance and balance control, we have developed a life-sized humanoid robot, WABIAN-RIII, which has 43 mechanical d.o.f. Through dynamic walking experiments, the validity of the proposed controls is verified.

The research of the anthropomorphic flutist robot at Waseda University, for more than ten years, has focused on reproducing as best as possible the human organs physiology involved on the human flute playing to clarify the mechanism from an engineering point of view. This research is based on the need to develop useful robots for practical uses in the human living environment. As a result of our research, the newest anthropomorphic flutist robot WF-4 (Waseda Flutist No. 4) with 24-DOF has been developed, which not only improved the expressiveness but reduced also the dimensions of all their mechanisms as closer to human size. In this paper, the flutist robot is used as a tool to help a human professor to improve the sound quality of beginner flutist players. In such a case, the robot is not only used to reproduce human flute playing but to evaluate also pupil's performance and to provide useful verbal and graphical feedback in order to improve his/her performance. Therefore, while robot is transferring the basics of the skill to students; teacher is taking care about how to motivate them (student's psychology). An experimental setup was designed to compare the added value of using the flutist robot for teaching to beginner students against the conventional way of teaching. Students' performances have been analyzed through different methods. The results demonstrated that the performance of pupils were better when the robot was used.

This paper describes the mechanisms and the speech production of a new advanced talking robot WT-3 (Waseda Talker-No.3) that improved on WT-2 (Waseda Talker-No.2) and based on human acoustic theory for the reproduction of human speech. WT-3 consists of 1-DOF lungs and 3-DOF vocal cords and articulators (the 7-DOF tongue, 5DOF lips, 1-DOF teeth, nasal cavity and 1-DOF soft palate), and could reproduce human-like articulatory motion; the total DOF was 18. The oral cavity was designed based on the MRI images of a human sagittal plane, although the cross section of the vocal tract was rectangular in shape except for the mouth. The width of the vocal tract was 30 [mm]. The average length of the vocal tract was approximately 175 [mm] and the same as that of a human's. Compared to the previous robots, WT-3 could produce vowels more clearly, and produce stops, fricatives and nasal sounds with the new flexible mechanisms that functioned as the human vocal tract area and the other mechanisms. WT-3 could mechanically reproduce human speech.

This paper describes an compliance control algorithm for biped walking robots. A walking cycle of a biped walking robot consists of three major phases such as a swing phase, a transition phase and a stance phase. Depending on the phases, the parameters of the compliance control are adjusted in real-time. When the landing foot contacts the ground, the large damping coefficient of the compliance is applied to the landing foot for contact force suppression. In the stance phase (double support phase), the large stiffness is given for increase of momentum. Also, a motion control of the trunk and waist is proposed to compensate for moments generated by biped walking motion. To explore human walking motion, a forty-three mechanical degrees biped robot is constructed. Its height and weight are about 1.88[m] and 130[kg], respectively. Through dynamic walking experiments, the control methods are verified.

Since 1990, we have been developing anthropomorphic flutist robots which are mechanically similar to human organs needed for playing the flute. The goal of this research is to clarify the flute playing mechanism from an engineering point of view and to enable the communication with humans at emotional level. The control of the air beam parameters for obtaining a good sound is very important. Such parameters are related mainly to the lips shape and its relative position respect to the flute embouchure hole. Then, the newest version of the anthropomorphic flutist robot WF-4 has been implemented by improving the design of each part of the robot (lips, lungs, neck, etc.). This new version has succeeded in the improvement of the flute sound quality and the sound conversion efficiency. In this paper, we describe the mechanical features of the WF-4 and the experiments done for evaluating its musical performance.

Almost all conventional biped humanoid robots have difficulties in realizing various walking motions such as knee stretch walking like a human because of an insufficiency of DOF. Therefore, we have developed a 16-DOF biped humanoid robot without a trunk: 3-DOF in each ankle, 1-DOF in each knee, 3-DOF in each hip and 2-DOF in the waist. Using the biped robot, basic experiments are conducted and the effectiveness of the leg mechanism is confirmed.

In this paper the mechanical design for a new 7-dofs leg is investigated as a walking module for a humanoid robot. In particular, a dynamic simulation is deduced by means of a Newton-Euler formulation and implemented numerically in order to compute the needed input actuator torques. A simulation is carried out for a similar built leg prototype that is used as a walking module for WABIAN-RIV (WAseda BIped humANoid robot-Revised IV). Experimental tests are carried out on this existing leg in order to validate the proposed formulation for a similar application. Thus, the validated formulation has been used in order to design the actuators for a new leg prototype.

The authors developed the auditory, tactile and olfactory sensation for a human-like head robot WE-3RV (Waseda Eye N0.3 Refined V. We used 2-layerd FSRs (Force Sensing Resistors) for tactile sensation, and WE-3 RV can recognize the difference in touching behaviors such as push, hit and stroke. For olfactory sensation, we used four semiconductor gas sensors. WE-3RV could quickly recognize the smells of alcohol, ammonia and cigarette smoke.

This paper describes the researches on the dental robotics those approach to the human jaws motion control system from robotics field. Patient robot and doctor robot are useful to develop a human jaw&apos;s total model. The authors have developed a mastication robot and mouth opening training robot those simulate patient and doctor respectively.

The goal of our research is to clarify factors that are necessary for coexistence between human and robot. However, evaluating communications between humans and robots is quite difficult due to the existence of several uncertain factors that exist in human communication and variety of personalities. Therefore, as a first step, a more previous species, rats were selected. We conducted interactive experiments between rats and robots. We investigate basic factors that are necessary for symbiotic relationship between living creatures and robots.
To conduct such experiments, we developed a new rat-robot (WM-6). and experiment systems. Three experiments have been conducted: "calling robot", "recognizing behavior", and "choosing reward". The results of these experiments show that we succeeded in making a rat to act on the robot by itself. Moreover the rat could recognize two behavioral patterns of the robot ("translation" and "rotation"). Finally, the rat could change its interaction with the robot based on its need. Consequently, we succeeded in creating various interactions between rat and robot.

This paper describes the knee stretch walking of the biped robot that has three degrees of freedom (DOF) in the ankle, one DOF in the knee and three DOF in the hip. To create the stable stretch walking pattern, a walking pattern generation method capable of specifying arbitrarily the knee joint angle is introduced. The singularity of the swing leg that can exist in single support phase will be avoided by the motion of the waist. The waist motion is calculated by a compensatory motion algorithm to cancel the moments generated by the motion of the lower-limbs. Through stretch walking simulations, the effectiveness of the pattern generation method is confirmed.

This paper describes the 6 degrees of freedom (6-DOF) jaw training robot that manipulates the patients jaw and its clinical results. Patients having disorders on their jaw joint who can&apos;t control the jaws not only open/close but also sideways are the target of this research. The authors have developed a 6-DOF slave manipulator and 3-DOF master manipulator for these patients. Natural jaw motion to sideway was simulated by changing the center of rotation according to the rotational direction of the mandible. Real training for the patient who has disorders on the jaw joint was done and the distance to sideway was increased 9 to 15 [mm] in right jaw joint and 7 to 12 [mm] in left.

This paper describes a new leg module for biped locomotors. We have developed a biped locomotor, WL-15 (Waseda Leg 15), which is applicable to various fields, such as medical, welfare and entertainment. WL-15 consists of parallel mechanisms such as a high stiffness, high positioning accuracy and easily calculated inverse kinematics. A walking control program is created on the basis of SIMULINK and RT-LAB executed on Windows NT and QNX target system. Using WL-15, dynamic walking with the step time of 0.8 [sec/step] to 1.92 [s/step] and turning step of 90 is conducted, and the effectiveness of WL-15's parallel mechanisms is confirmed.

This paper describes a macro-walking instruction strategy for a biped humanoid robot to memorize complex walking patterns systematically and effectively. In teaching various walking motions, auditory sensors are employed. Based on the sensory information, the motion of lower-limbs is created in online by a pattern generator At the same time, the motion of the trunk and the waist is generated in online by a balance control method for walking stability. A complete walking pattern is hierarchically constructed on the basis of basic and advanced walking patterns. Using WABIAN-RV, many experimental tests are conducted, and the effectiveness of the teaching strategy is verified.

In this paper a mouth opening and closing training robot named as WY-5 (Waseda Yamanashi version 5) is analyzed in terms of stiffness characteristics. Basic models and a formulation are proposed in order to deduce the stiffness matrix as a function of the most important stiffness parameters of the WY-5 architecture. A numerical simulation is also presented to discuss main features of the system.

In this paper, basic models and a formulation are presented for the stiffness analysis of the humanoid robot WABIAN-RV An evaluation of stiffness performances is carried out by numerically implementing the proposed formulation. An experimental validation of the numerical results is also carried out.

In this paper a biped locomotor named as WL-15 (Waseda Leg 15) is analyzed in terms of stiffness characteristics. Basic models and a formulation are proposed in order to deduce the stiffness matrix as a function of the most important design parameters of the WL-15 architecture. First numerical simulations and experimental tests are also carried out for stiffness performance estimation.

This study is aimed at the realization of dynamic biped walking in human living or/and working environments. We, therefore, have constructed a two-legged humanoid robot having a trunk, WABIAN-RII (WAseda BIped humANoid robot-Revised II) which has forty-three mechanical degrees of freedom. The motion of its lower-limbs is used to locomote while the motion of its trunk and waist is employed to balance its whole body. In this paper, how to make a walking pattern and cancel moments generated by the motion of the lower-limbs is described. A lower-limb's motion pattern is generated by a polynomial, and a motion of the trunk and waist is determined by a moment compensation control based on ZMP (Zero Moment Point) and the motion of the head, lower-limbs and upper-limbs. The effectiveness of the proposed method is demonstrated by various dynamic walking experiments on a plane.

The application of robots in contact with humans, in services or assistance, implies the realization of effective and acceptable human-robot interaction.
In humans, vision plays a significant role in social interaction, like for example in the recognition of faces and expressions, as well as in gesture understanding.
Visuo-motor coordination of eye and neck movements in humans presents high performances in terms of accuracy, speed, effectiveness. This is due to the mechanical, cinematic, and dynamic features of the head muscular-skeletal apparatus and to the peculiar processing of visual data, detected with a space variant resolution.
The work presented in this paper aims at employing retina-like cameras on a human-like robotic head, reproducing similar degrees of freedom, ranges of motion, speeds, and accelerations of human neck and eye movements, in order to improve visuo-motor coordination. The use of retina-like cameras allows a faster human-like processing of visual information, better suited for the control of head movements. On the other hand, retina-like cameras provide high resolution information only in a small area of the image and thus need to be dynamically focused on the points of interest.
Experimental trials were focused on the capability of identifying and tracking human faces, as a first step of human-robot interaction. Preliminary experimental results show the feasibility of a smooth face tracking, by a closed control loop for the head movements, based on retina-like vision.

This paper describes a control and a structure of a battery driven bipedal robot, WL-15(Waseda Leg-15), which has a 6-DOF parallel mechanism. WL-15 has been designed as a multi-purpose locomotor of robotic systems. This robot is controlled by the QNX real-time operating system. Using Math Works' SIMULINK and ORAL-RT's RT-LAB executed on Windows NT and QNX target systems, control software and pattern generator are developed A walking control capable of dealing with various dynamic walking is proposed and tested indoors and outdoors using the WL-15. Dynamic biped walking is realized with the maximum step length of 200[mm], the maximum walking speed of 0.8[s/step] and the minimum speed of 1.92[s/step]. Also, the WL-15 is confirmed to be able to turn 90[deg] in two steps and carry a load of 18[kg].

In this paper a humanoid robot named as WABIAN-RIV (WAseda BIpedal humANoid Refined IV) is analyzed in terms of stiffness characteristics. This paper proposes basic models and a formulation in order to deduce the stiffness matrix as a function of the most important stiffness parameters of the WABIAN architecture. The proposed formulation is useful for numerical estimation of stiffness performances.

This paper describes a jaw movement training robot system implementing a 6 degrees of freedom (DOF) parallel mechanism, and its application for lateral movement training. Temporomandibular joints (TMJ) problem is a disorder, whereby patients are not able to open their mouths nor move their jaws easily because of the problems with the mandibular joints, mastication muscles, and other organs concerning food chewing. Conventional therapy has been done with simple mouth opening apparatuses based on a doctor's technique through their own experiences, while this is still common. The authors have developed and improved a jaw movement training robot system, which provides not only jaw open and close training but also jaw lateral movement training. This system consists of a 6-DOF slave manipulator as a patient working manipulator and a 3-DOF master manipulator as a doctor commanding manipulator.

METI has launched a national 5-year-project called Humanoid Robotics Project (HRP) since 1998 FY. Because humanoid robots have a human-like figure and can walk in a biped way and can take an action like a human being, we consider applying the humanoid robot platform in HRP to service fields of caring people such as the elderly, patients, etc. Taking the technical limitation of the current humanoid robot into account, we assume a situation where the robot serves such people. We regard the robot as users' avatar or another existence of users, and consider the class of users: a nurse, a patient, and a person in a remote site. This allows us to propose four types of user interfaces for the humanoid service robot system: an on/off-line user interface for a nurse who wants to control the robot as his avatar, a user interface for a patient who wants to control the robot as another existence, and a user interface for a person in a remote site who wishes to control the robot as his avatar. These user interfaces are described in this paper.

In this paper, we describe an anthropomorphic flutist robot that it's expected to have human-like organs from the mechanical hardware and control functions. We developed a "General Position" searching algorithm, which is based on the relative distance between the robot's mouth and the flute mouthpiece. It is possible for the robot, using the General Position, to blow a whole tone. Thereafter, we developed an autonomous searching algorithm for the lip part parameters after setting the General Position, and an algorithm for evaluating the blowing sound. The robot could stably play a flute using these algorithms.

The authors have been developing human-like head robots in order to develop new head mechanisms and functions for a humanoid robot that has the ability to communicate naturally with a human by expressing human-like emotion. Furthermore, the interaction between humans and robots is one of the essential factors for the Neuro-Robotics. We believed that the Mental Dynamics caused by the stimuli from the internal and external environment is important in expressing emotion. Therefore, we newly developed a ye No.4) in 2002. human-like head robot WE-4 (Waseda E The "Learning System", the "Mood Vector" and the "Second Order Equations of Emotion" were introduced to the mental model of the robot. Moreover an internal clock was introduced as an autonomic nerve system to express the activation component of the Mood Vector. And, we realized the expression of mental transition caused by the stimuli from the internal and external environment of the robot. In this paper we describe the new mental model of a human-like head robot WE-4.

This paper describes the knee stretch walking of the biped robot that has three degrees of freedom (DOF) in the ankle, one DOF in the knee and three DOF in the hip. To create the stable stretch walking pattern, a walking pattern generation method capable of specifying arbitrarily the knee joint angle is introduced. The singularity of the swing leg that can exist in single support phase will be avoided by the motion of the waist. The waist motion is calculated by a compensatory motion algorithm to cancel the moments generated by the motion of the lower-limbs. Through stretch walking simulations, the effectiveness of the pattern generation method is confirmed.

The authors have been developing human-like head robots in order to develop new head mechanisms and functions for a humanoid robot that has the ability to communicate naturally with a human by expressing human-like emotion. We believe that in the future, it will be necessary for personal robots to generate active behavior to interact bilaterally between human and robot. Therefore, we developed an Emotion Expression Humanoid Robot WE-4R ((W) under bar aseda (E) under bar ye No.(4) under bar (R) under bar efined) in 2003. The Need Model consisting of the "Appetite, the "Need for Security" and the "Need for Exploration was introduced to the mental model for humanoid robots. We also defined the "Need Matrix" and introduced the "Equations of Need" to describe the robot needs. Robots with the need model can generate and express active behavior according to their need. This paper describes the need model that is implemented in the Emotion Expression Humanoid Robot WE-4R.

This paper describes the modeling and analysis of an elastic tongue mechanism of a talking robot WT-2 and the development of an acoustic simulator for the construction of the computational model of human speech production. WT-2 consists of lungs, vocal cords and articulators. It is essential to accurately estimate and analyze the shapes of these organs to develop an acoustic simulator However it was difficult to estimate and analyze the mechanisms, because they were composed of an elastic rubber to make various shapes and to seal the air and sound Therefore, we constructed a modeling method to simulate the shape of the elastic mechanisms. This method is applicable to all the elastic body. We developed an acoustic simulator using this modeling method in the process of constructing the speech production model.

This paper describes a control method for a stable biped walking on uneven terrain. The walking control consists of a position control and a compliance control. In order to realize dynamic walking on a human living environment, a biped locomotor is controlled by the position control based on a compensatory motion. Also, in this research, to reduce the magnitude of impact forces and to guarantee a stable landing on the ground, the position-based virtual compliance control is introduced. Several walking experiments on uneven terrain are conducted using WL-15 (Waseda Leg-15) and the effectiveness of the control method is confirmed.

This paper describes the development of a new talking robot WT-2 that improved on WT-1R and has advanced vocal tract mechanisms for the reproduction of human vocal movement. WT-2 consists lungs, vocal cords, a vocal cavity and nasal cavity; the total DOF is 15. The length of the vocal tract is about 175[mm] and is almost the same as that of an adult male. Compared to WT-1 or WT-1R developed previously, WT-2 could utter Japanese vowels more clearly, and produce stops, fricatives and nasal sounds by a new flexible tongue mechanism as well as decrease sound leaks from the tongue except those from the lips or nostrils.

The goal of our research is to clarify factors that are necessary for coexistence between human and robot. However, evaluating communications between humans and robots is quite difficult due to the existence of several uncertain factors that exist in human communication and variety of personalities. Therefore, as a first step, a more previous species, rats were selected. We conducted interactive experiments between rats and robots. We investigate basic factors that are necessary for symbiotic relationship between living creatures and robots.
To conduct such experiments, we developed a new rat-robot (WM-6). and experiment systems. Three experiments have been conducted: "calling robot", "recognizing behavior", and "choosing reward". The results of these experiments show that we succeeded in making a rat to act on the robot by itself. Moreover the rat could recognize two behavioral patterns of the robot ("translation" and "rotation"). Finally, the rat could change its interaction with the robot based on its need. Consequently, we succeeded in creating various interactions between rat and robot.

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This paper proposes a follow-walking motion for biped humanoid robots based on a stabilization control and a complete walking-motion pattern. To follow human motion, the unit patterns of the trunk, the waist and the lower limbs are generated and synthesized. During the follow motion, the biped robots are balanced by the stabilization control that calculates the combined motion of the trunk and the waist that compensates for the moments produced by the motion of the lower limbs. For confirmation of the follow-walking motion, we have developed a life-sized humanoid robot, WABIAN-RII (WAseda BIped humANoid robot-Revised II). It has a total of 43 mechanical d.o.f.
two 6-d.o.f. legs, two 10-d.o.f. arms, a 4-d.o.f. neck, 4-d.o.f. in the eyes and a torso with a 3-d.o.f. waist.

This paper describes an online method generating walking patterns for biped humanoid robots having a trunk. Depending on the walking command, the motion patterns of the lower-limbs are created and connected to the prewalking patterns smoothly in online. For the stability of the biped robots, the trunk and the waist motion is generated by a walking stabilization control that is based on the ZMP trajectory and the motion of the lower-limbs. Experimental tests of versatile biped walking on a plane surface are conducted using an auditory interface, and the validity of the online pattern generation method is verified.

This paper describes two humanoid robots developed in the Humanoid Robotics Institute, Waseda University. Hadaly-2 is intended to realize information interaction with humans by integrating environmental recognition with vision, conversation capability (voice recognition, voice synthesis), and gesture behaviors. It also possesses physical interaction functions for direct contact with humans and behaviors that are gentle and safe for humans. WABIAN is a robot with a complete human configuration that is capable of walking on two legs and carrying things as with humans. Furthermore, it has functions for information interactions suite for uses at home.

This study is aimed at the realization of a continuous walking-pattern generated by combining some different patterns such as turning, forward, backward and side step patterns. A biped-walking robot is required to have the function of followability and stability to achieve continuous follow walking in a human’s living environment. Unit patterns for a biped locomotion are continuously generated by a walking pattern generator, and the complete walking pattern for followability is determined by synthesizing the unit patterns. The compensatory motion of the trunk and waist that is calculated by a stabilization control method ensures the stability of combined walking patterns. To explore human-like walking, we have constructed a two-legged robot, WABIAN-RII (WAseda BIpedal humANoid robot-Revised II). Through hardware experiments, the continuous biped walking is realized.

This study is aimed at the development of human-like biped robots and the realization of various biped-walking motions. We have constructed a life-sized humanoid robot called WABIAN-RII (WAseda BIped humANoid robot-Revised II) that has a total of forty-three mechanical degrees of freedom (DOF); two six DOF legs, two ten DOF arms, a four DOF neck, four DOF in the eyes and a torso with a three DOF waist. The biped humanoid robot is required to have the function of stability, followability and environmental adaptability to achieve human-like walking. A walking pattern generator generates unit patterns for a biped locomotion, and the complete walking pattern for followability is determined by synthesizing the unit patterns. The compensatory motion of the trunk and waist that is calculated by a balance control method ensures the stability of combined walking patterns. Through hardware experiments, we have realized follow walking, emotional walking, continuous walking and so on.

This paper describes the latest research on dental robotics done by the authors. Two kinds of robots are included in the dental robotics, mouth-opening and - closing training robot and skull robot, as doctor and patient model respectively. Mouth opening and closing training robot is a doctor model having 6 degrees of freedom (DOF) that is designed for the mouth opening and closing training. Conventional mouth opening apparatuses such as wooden screws, bile blocks and clothespins-type apparatus, only increase mouth opening distance and do not have actuators, sensors, and/or control systems. Skull robot is a patient model having plastic human skull model. By integrating these two robots, the authors are planning to develop the total dental robot system.

The authors have been developing human-like head robots in order to develop new head mechanisms and functions for a humanoid robot that has the ability to communicate naturally with a human by expressing human-like emotion. When humans communicate through auditory or visual sensations, they estimate their mental state through not only the information of each sensation but also their mental model. A robots mental model consists of a 3D mental space having a pleasantness, an activation and a certainty axes. When the robot senses the stimulus, a mental vector moves in this mental space based on the Equations of Emotion. We also proposed a Robot Personality, which consists of the Sensing Personality and the Expression Personality. Further, we assigned and loaded various Sensing Personalities.

Vocal movement isn't only, a movement of the vocal organs. It is also a movement that produces acoustic signals received by hearing as linguistic information through hydroacoustic phenomena along with the formation of the vocal way.
The purpose of this research is to make clear the human vocal mechanism from the view of engineering by simulating the vocal movement with a robot, and to create the dynamic model.
Therefore, the authors developed an anthropomorphic talking robot WT-1 (Waseda Talker-No.1) in 1999. It simulates human vocal movement, and has articulators (the 6-DOF tongue, 4-DOF lips, 1-DOF teeth, a nasal cavity and 1-DOF soft palate) and vocal organs (the 1-DOF lungs, 1-DOF vocal cords); Total DOF of the robot is 14.
We experimented with it on vowels. As a result, F1 and F2 frequencies of all Japanese vowels were similar to the human averages. WT-1 could titter single vowels. However, its voice wasn't natural.
In this paper we describe the improvement of the mechanisms for the realization of natural vowels and consonant sounds.

The authors have been developing human-like head robots in order to develop new head mechanisms and functions for a humanoid robot that has the ability to communicate naturally with a human by expressing human-like emotion. We were able to four sensations (the visual, auditory, cutaneous and olfactory sensations) of a humane five senses by developing WE-3RIV ((W) under bar aseda (E) under bar ye No. (3) under bar (R) under bar efined (IV) under bar). In this paper, we targeted olfactory sensation and facial color that humans use to communicate with each other A human olfactory sensation recognizes over a thousand smells. WE-3RIV can recognize the smell of alcohol, ammonia and cigarette smoke. Our olfactory sensor consists of four semiconductor gas sensors. WE-3RIV was able to recognize the recognition of certain smells within a few seconds of being presented with the smell stimuli by using sensor output and changing rate of the sensor output. Further, we developed the facial color expression using red EL sheets. By adding the facial color expression, the expressiveness of the robot and the recognition rate of a robot facial expression were improved.

This paper describes the skull robot as a patient simulator for the mouth opening and closing training. The rehabilitation for the patients who have problems on the jaw joint have been done primarily based on the doctor's qualitative experience and technique that is unknown to other people. The authors developed a skull robot WOJ-1R as a mechanical patient simulator. This skull robot will be useful for the doctor to develop the strategy of training for the real human patient. Also, it will quantitatively clarify the effectiveness of the robots therapy compared with therapy by human. Experimental result of biting force comparison, robot therapy force data acting on the skull robot was smaller than the conventional therapy by human.

This paper describes the remote training between Tokyo and Yamanashi with 6 degrees of freedom (DOF) parallel robot that is designed for the mouth-opening and -closing training. Remote training is useful for the patients who have difficulties to go to hospitals frequently. The authors have developed a master-slave training system using ISDN lines because ISDN is not difficult to come by in patients home. Mouth-opening and -closing training robot WY-5R (Waseda Yamanashi-5 Refined) realized the remote training via two ISDN lines with 128 kbps. As a result of remote therapy using WY-5R, two patients' mouth-opening and -forward distances increased.

The purpose of this research is to clarify the human vocal mechanism from engineering viewpoints by simulating vocal movement with a robot, and to create a dynamic model.
The authors developed an anthropomorphic talking robot WT-1 (Waseda Talker-No.1) in 1999. It simulates human vocal movement, and has articulators and vocal organs. WT-1 could speak Japanese vowels (\a\, \i\, \u\, \e\, \o\). However, its vowels weren't natural.
Therefore, we developed a talking robot WT-1R (Waseda Talker-No.1 Refined) that improved WT-1 for the realization of natural vowels and consonant sounds in 2000. WT-1R has articulators (the 6-DOF tongue, 4-DOF lips, 1-DOF teeth, a nasal cavity and a 1-DOF soft palate) and vocal organs (the 1-DOF lungs, 2-DOF vocal cords). The total DOF of the robot is 15.
This paper describes the improved mechanisms of WT-1R and the realization of the fluctuation for the natural voice and the clearness of vowels.

The authors have been developing human-like head robots in order to develop new head mechanisms and functions for a humanoid robot that has the ability to communicate naturally with a human by expressing human-like emotions. We think that the personality of the robot is extremely important in attaining smooth and effective communication. We introduced a robot personality that consists of the Sensing Personality and the Expression Personality. The Sensing Personality determines how a stimulus works for a robots mental state. A 3D mental space was defined in the robot. Seven emotions were mapped out in the 3D mental space. After the robot determines its emotion, it expresses its emotion by the Expression Personality. We expressed the Expression Personality using a matrix. Moreover, we assigned and loaded six robot personalities into the robot. The robot can express various personalities.

This paper describes a locomotion control for biped humanoid robots based on a balance control and an impedance control. The balance control is employed during a whole walking cycle, which can compensate for the moments generated by the biped walking. In the control, the compensatory motion of the trunk and waist is calculated from the trajectories of the lowerlimbs, arms, head and ZMP. The parameters of the impedance control are adjusted in real-time according to the gait phase. The large damping coefficient of the impedance is applied to the landing leg to absorb the impact/contact force during the contact phase, while the large stiffness is given to increase the momentum reduced by the viscosity of the landing leg during the first half single support phase. By dynamic walking experiments using a human-like robot WABIAN-RIII, the validity of the proposed control methods is verified.

This research is aimed at the development of bipedal humanoid robots working in human living space, with a focus on its physical construction and motion control method. At the initial stage, we developed a 35 DOF bipedal humanoid robot WABIAN (WAseda BIpedal humANoid)[1] in 1996, and proposed a control method for dynamic cooperative biped walking. By this control method, we have realized a various number of patterns, such as dynamic forward or backward walking, marching in place, dancing, and carrying a load. In this paper, we presented a quasi real-time walking control of a bipedal humanoid based on those walking pattern syntheses. Concretely, we developed a follow-walking control method with a patterns switching technique for a bipedal humanoid robot to follow human motion through hand contact, as an application to a human-robot physical interaction. At the same time, we adopted a 6-axis force-torque sensor system to WABIAN's hand. By using the control methods, WABIAN has been able to perform dynamic marching in place, walking forward and backward during a continuous time while someone is pushing or pulling its hand in such a way.

The vocal movement isn't only a movement of the vocal organs. It is also a movement that produces acoustic signals received by hearing as linguistic information through hydroacoustic phenomena along with the formation of the vocal way.
The purpose of this research is to make clear human vocal mechanism from the view of engineering by reproducing the vocal movement using a robot, and to make the dynamic model.
Therefore, the authors developed an anthropomorphic talking robot, WT-1 (Waseda Talker-No.1) in 1999. It simulates human voice movement, and has articulators (the 4-DOF lips, 1-DOF teeth, 6-DOF tongue, nasal cavity and 1-DOF soft palate) and the vocal organs (the 1-DOF vocal cords, 1-DOF lungs); Total DOF of the robot is 14.

We would like to give biped humanoid robots a follow motion as one of functions capable of supporting humans. Unfortunately, so not much attention has been paid to the researches on human-follow motions up to date. In this paper, a follow-walking control method is described to realize the follow-walking motions, which consists of a pattern, synthesis and a balance motion control. First, we generate switchable unit patterns of a biped humanoid robot, based on the human-robot interaction. Second, the unit patterns are synthesized according to the sense of resultant contact forces. Finally, the compensatory motion of the trunk and waist is calculated by a cooperative motion control algorithm for the balance of the biped robot.

This paper describes the remote training with 6 degrees of freedom (DOF) par allel robot that is designed for the mouth-opening and -closing training. The rehabilitation for the patient who have problems on the jaw joint, mastication muscles, or other organs concerning the food chewing have been done primarily based on the doctor's qualitative experience and technique. Conventional mouth opening apparatuses (such as wooden screws, bite blocks and clothespins-type apparatus) only increases the mouth-opening distance and do not have the actuators, sensors, and/or control systems. Moreover, during therapy, the quantitative data is unknown in spite of its importance for the standardization of mouth-opening and -closing training. Mouth-opening and -closing training robot WY-5R (Waseda Yamanashi-5 Refined) realized the remote training via ISDN line. As a result of remote therapy using WY-5R, the patient's mouth-opening distance increased.

In this paper, we introduce an attempt to realize communication between rats and rat-robots for the advancement of communication between humans and robots. By repeating certain interactions between rats and robots, we aim to clarify the effective factors in communication. The experimental system is equipped with a CCD camera above the experimental field. The positions of the rat and the rat-robot are calculated in real-time. We have developed the Rat-Robot WM-5 (Waseda Mouse - No.5). The main features of the robot consist of the similarity in figure and size, the remote control by an FM receiver, the ability to change direction on the spot by the use of a two-wheel mechanism, the shaking of the head, and the behavioral imitation of a rat's mounting. An interactive experiment between a rat and a rat-robot was carried out with the developed system. The rat's behaviors were compared in two cases. The rat-robot mounted the rat in one situation but didn't do it in another. We observed that the robot's action of mounting the rat makes the rat more interested in the robot for longer period of time, and thus the mounting of the robot by the rat occurred. As a result, the imitation of the rat's mounting seems likely to work well in the communication between rats and rat-robots.

This paper describes three emotions such as happiness, sadness and anger. The emotions are realized by the walking patterns of a biped personal robot that are defined by the parameterization of its whole body motion. The combined motion of the waist and trunk calculated by the compensatory control algorithm that has been proposed already is used to cancel the moments generated by the motions of the head, the lower-limbs and the upper-limbs. To experiment emotion expression, we have constructed a human-like personal robot WABIAB-RII (WAseda BIpedal humANoid robot-Revised II) that has forty-three mechanical degrees of freedom and four passive degrees of freedom. Simulation and experimental results of emotional walking are also presented.

The authors have been developing anthropomorphic head robots in order to develop a new head mechanisms and functions for a humanoid robot having the ability to communicate naturally with a human by expressing human like emotion. the developed the anthropomorphic head-eve robot "WE-3RIV" (Waseda Eye No.3 Refined IV) which has four sensations and facially expressing emotions in 2000. We newly added the olfactory sensation and the facial color expression function to its previous model, WE-3RIII, and we improved and rebuilt its artificial psychological model that consists of a 3D mental space having a pleasantness, an activation and a certainty axes When the robot senses the stimulus, a mental rector moves in the mental space based upon a set of differential equations in the mathematical formulation. We named it "Equations of Emotion." We also introduced the Robot Personality, which consists of the Sensing Personality and the Expression Personality. WE-3RIV realized to express the mental state affected by various stimuli based on the Equations of Emotion and the Robot Personality.

This paper describes the emotional walking of a biped humanoid robot based on its body motion. We consider three emotions such as happiness, sadness and anger. These emotions are defined by motion parameters of the biped robot. To express the emotions as walking motions, the patterns of the low-limbs, upper-limbs and head axe preset using a polynomial. While the biped robot is emotionally walking according to the patterns, its stability is maintained by using the combined motion of the trunk and waist that is calculated by a body motion control method. To confirm the emotion expression, we have constructed a human-like robot WABIAB-RII (WAseda BIpedal humANoid robot-Revised II) which has forty-th-ree mechanical degrees of freedom.

This paper describes the mechanism, control method, and training results of the 6 degrees-of-freedom (DOF) mouth-opening and -closing training robot WY-5 (Waseda Yamanashi No. 5) that is an application of the Universal Dental Robot (UDR). The mouth-opening training is indicated for the rehabilitation of the patients suffering from disturbance of the mouth-opening and -closing. The six linear actuators manipulate the u-shaped end-effector of UDR. This u-shaped end-effector is a moving platform of 6-DOF parallel manipulator. Each linear actuator has displacement, velocity, and force sensor to measure the position and orientation of the u-shaped end-effector. The WY-5 is a master-slave parallel robot that manipulates the patient's mandible that can't widely open. The doctor grasps the 2-DOF master manipulator, and the 6-DOF slave manipulator opens the patient's mandible according to the master manipulator's motion. As the result of therapy by using WY-5 for two female patients who cannot open their mouth widely, the mouth opening distance increased.

To explore issue of developmental structure and human-like motion, we have constructed a human-like biped robot called WABIAN-RII (WAseda BIped hu-mANoid robot-Revised If) that has a total of forty-three mechanical degrees of freedom (DOF); two six DOF legs, two ten DOF arms, a four DOF neck, four DOF in the eyes and a torso with a three DOF waist. We present a follow-walking control with a switching pattern technique for the biped robot to follow human motion. Also, emotional walking of the biped robot is described, which expresses emotions by parameterizing its motion. The follow walking and emotion expression can be realized by the compensation of moment by the combined motion of the waist and trunk.

This paper describes a balance control of biped locomotion systems. A biped humanoid robot is modeled and studied focusing on the realization of humanlike walking. Firstly, the smooth motion of its lower-limbs is characterized in terms of a set of walking variables. Secondly, to cancel moments produced by the motion of the lower-limbs, the motion of its trunk and waist is derived by an iteration method. Finally, a program control using a preset walking motion is applied to the biped robot. To confirm of human-like walking, we have constructed a human-like biped robot called WABIAN-RII (WAseda Blped humANoid robot-Revised II) that has a total of forty-three mechanical degrees of freedom (DOF). Experiments of a human-follow walking are conducted using the WABIAN-RII.

The vocal movement isn't only a movement of the vocal organs. It is also a movement that produces acoustic signals received by hearing as linguistic information through hydroacoustic phenomena along with the formation of the vocal way.
The purpose of this research is to make clear human vocal mechanism from the view of engineering by reproducing the vocal movement using a robot, and to make the dynamic model.
Therefore, the authors developed an anthropomorphic talking robot, WT-1 (Waseda Talker-No.1) in 1999. It simulates human voice movement, and has articulators (the 4-DOF lips, 1-DOF teeth, 6-DOF tongue, nasal cavity and 1-DOF soft palate) and the vocal organs (the 1-DOF vocal cords, 1-DOF lungs); Total DOF of the robot is 14.

The last few years have been characterized by the continuous development of information and communication technologies, robotics technologies, and home automation technologies. The number of application areas for such technologies is increasing, especially in fields rather outside the pure industrial scenario, often identified as "service applications." These are healthcare, public service provisions, social services for disadvantaged citizens, technical aids for promoting the independence of disabled and elderly people, and many others. With this joint research Scuola Superiore Sant' Anna and Waseda University, starting from the current availability of several mechatronic prototypes in their research laboratories, intend to validate different telecommunication tools for the remote control of mechatronic systems by demonstrating the feasibility and potential benefits deriving from the integration of such technologies.

In this study: the authors have been developing anthropomorphic head-eye robots, in order to elucidate the human vision system from an engineering point of view and to develop a new head mechanism and function for a humanoid robot having the ability to communicate naturally with a human. We developed the anthropomorphic head-eye robot "WE-3RII" (Waseda Eye No.3 Refined II), with eyes, eyelids, eyebrows, lips, jaw and a neck. The robot has the ability to express an autonomous facial expression using three independent parameters of a psychological model. With the robot, the mechanism of changing eye movement from smooth pursuit eye movement to saccadic, and the control of scanning eye movement like that of a human's can be achieved. The robot is also able to express more humanlike motion in pursuing a target by changing its eyeball control parameters, rather than that of WE-3R which we developed in 1996 Therefore, the authors have confirmed that WE-3RII has the ability to realize a pursuing motion in three dimensional space with its autonomous facial expression adapting to the target position and brightness like a human.

We have proposed the collision-tolerant mobile manipulator equipped with a passive trunk. In collision experiments with unknown environments, results show that this mechanism is suitable for the suppression of contact forces which is an important issue for human-robot collaborations. The trunk with mechanical elements such as springs and dampers is passively deformed to deal with physical contacts, while the mobile platform moves around on the horizontal plane in response to friction between the platform and the ground. The end-effector of the manipulator, however, is difficult to track a desired task due to the deformation of the compliant trunk: and the mobility of the platform. In order to solve the problem, the desired joint configurations of the manipulator are directly calculated according to the movement of the trunk and the platform, and a feedback control scheme is employed.

In this paper, the authors introduce a life-size biped walking robot having antagonistic driven joints using a nonlinear spring mechanism and a dynamic biped walking control method using these joints.
In the current research concerning a biped walking robot, there is no developed example of a life-size biped walking robot with antagonistically driven joints by which the human musculo-skeletal system is imitated in lower limbs. Humans are considered ts walk efficiently using the inertial energy and the potential energy of the lower limbs effectively, walk smoothly with less impact force when a foot lands and cope flexibly with the outside environment. The Human joint is driven by two or more muscle groups. Humans can vary the joint stiffness, using nonlinear spring characteristics possessed by the muscles themselves. These functions are indispensable for a humanoid. However, the biped walking robots developed previously have been unable to walk in this way.
Therefore, the authors developed a biped walking robot having antagonistic driven joints, and proposed a walking control method for dynamic biped walking that uses antagonistic driven joints to vary joint stiffness. The authors performed walking experiments using the biped walking robot and the control method. As a result, dynamic biped walking varying the joint stiffness using antagonistic driven joints was realized.

The authors are engaged in studies of biped walking robots from the following two viewpoints. One is a viewpoint as a human science. The other is a viewpoint towards the development of humanoid robots. In the current research concerning a biped walking robot, there is no developed example of a life-size biped walking robot with antagonistically driven joints by which the human musculo-skeletal system is imitated in the lower limbs. Humans are considered to exhibit walking behavior which is both efficient and capable of flexibly coping with contact with the outside environment. However, developed biped walking robots cannot realize human walking. The human joint is driven by two or more antagonistic muscle groups. Humans can vary the joint stiffness, using nonlinear spring characteristics possessed by the muscles themselves. The function is an indispensable function for a humanoid. Therefore, the authors designed and built an anthropomorphic biped walking robot having antagonistic driven joints. In this paper, the authors introduce the design method of the robot. The authors performed walking experiments with the robot. As a result, a quasi-dynamic biped walking using antagonist driven joint was realized. The walking speed was 7.68 s per step with a 0.1 m step length.

The authors are engaged in studies of biped walking robots from the following two viewpoints. One is a viewpoint as a human science. The other is a viewpoint towards the development of humanoid robots. In the current research concerning a biped walking robot, there is no developed example of a life-size biped walking robot with antagonistically driven joints by which the human musculo-skeletal system is imitated in the lower limbs. Humans are considered to exhibit walking behavior which is both efficient and capable of flexibly coping with contact with the outside environment. However, developed biped walking robots cannot realize human walking. The human joint is driven by two or more antagonistic muscle groups. Humans can vary the joint stiffness, using nonlinear spring characteristics possessed by the muscles themselves. The function is an indispensable function for a humanoid. Therefore, the authors designed and built an anthropomorphic biped walking robot having antagonistic driven joints. In this paper, the authors introduce the design method of the robot. The authors performed walking experiments with the robot. As a result, a quasi-dynamic biped walking using antagonist driven joint was realized. The walking speed was 7.68 s per step with a 0.1 m step length.

This paper describes the quantification of masticatory efficiency by using a mastication robot that was developed as a mechanical simulator of human masticatory jaw motion on the basis of Dental Robotics. The masticatory efficiency has been researched on the basis of human mastication and the quantification of masticatory efficiency has been studied experimentally. in this paper, the authors used the sieving test to quantify efficiency. The results of chewing experiments with robot that compared the differences in chewing motion between clenching and grinding showed that the masticatory efficiency of the latter was higher than that of the former.

In this study the authors have been developing anthropomorphic head-eye robots, in order to elucidate the human vision system from an engineering point of view, and to develop a new human-friendly communication system.;We developed an anthropomorphic head-rye robot "WE-3R" (Waseda Eye No.3 Refined) as a human-friendly head-eye subsystem of a humanoid robot "Hadaly-2": WE-3R has eyelids as hardware while the functions of retina (adaptation) and iris (adjustment of the pupil diameter) are realized as software so WE-3R can adjust to brightness. The system can pursue objects in 3 dimensional space with adjusting to the brightness in a human-like manner that can be considered important for smooth and natural human-robot interaction.

The authors proposed the construction of a bipedal humanoid robot that has a head system with visual sensors, two hand-arm systems, 3DOF trunk, and antagonistic driven joints using the non-linear spring mechanism;mr, on the basis of WL-13 And we really designed and built it. In addition the first step to realize the dynamic cooperated motion of limbs and 3 DOF trunk, the authors developed the central algorithm and the simulation program that generates the trajectory of 3 DOF trunk for stable biped walking pattern even if the trajectories of upper mad lower limbs are arbitrarily set for locomotion and manipulation respectively Using this preset walking pattern with variable muscle tension references correspond to swing phase mad stance phase, the authors performed walking experiment of dynamic walking forward mad backward dynamic dance with 3 DOF trunk motion and carrying, on a flat level surface (1.28 s/step with a 0.15 m step length).
As a result the efficiency of our walking control algorithm and robot system was proved In this paper, the mechanism of WABIAN and its control method are introduced.

In this paper, we introduce a trial to realize interaction between creatures and robots. As the first step, rats were selected as an experimental target as a simplified form of interaction between human and humanoid robots. A rat robot was developed. Infrared transmitter similar outlook of rat's figure and size, font-wheel steering and rear-wheel driving mechanism were equipped to the robot as the main features of the robot. An experiment system was developed to enable interaction between the rat robot and rats. The experiment system is equipped with a color CCD camera which captures and processes images of the rat and the rat robot in real-time. Behavioral experiments were performed with the system. As a result, it was confirmed that behaviors of the rat robot influence the rat's behaviors.

The authors are engaged in studies of biped walking robots from the following two viewpoints. One is a viewpoint as a human science. The other is a viewpoint towards the development of humanoid robots.
In this paper, the authors introduce an anthropomorphic dynamic biped walking robot adapting to the humans' living floor. The robot has two remarkable systems: (1) a special foot system to obtain the position relative to the landing surface and the gradient of the surface during its dynamic walking; (2) an adaptive walking control system to adapt to the path surfaces with unknown shapes by utilizing the information of the landing surface, obtained by the foot system. Two units of the foot system WAF-3 were produced, a biped walking robot WL-12RVII that had the foot system and the adaptive walking control system installed inside it was developed, and a walking experiment with WL-12RVII was performed. As a result, dynamic biped walking adapting to humans' floors with unknown shapes was realized. The maximum walking speed was 1.28 s/step with a 0.3 m step length, and the adaptable deviation range was from -16 to +16 mm/step in the vertical direction, and from -3 to +3 degrees in the tilt angle.

The authors are engaged in studies of biped walking robots from the following two viewpoints. One is a viewpoint as a human science. The other is a viewpoint towards the development of humanoid robots.
In the current research concerning a biped walking robot, there is no developed example of a life-size biped walking robot with the antagonistically driven joints by which the human musculoskeletal system is imitated in lower limbs. Humans are considered to exhibit walking behavior, both efficient and capable of flexibly coping with contact with the outside environment. However, developed biped walking robots can not realize the human walking. The human joint is driven by two or more antagonistic muscle groups. Humans can vary the joint stiffness, using nonlinear spring characteristics possessed by the muscle themselves. The function is an indispensable function for a humanoid.
Therefore, the authors designed and built an anthropomorphic biped walking robot having antagonistic driven joints. In this paper, the authors introduce the design method of the robot. The authors performed walking experiments with the robot. As a result, quasi-dynamic biped walking using antagonist driven joint was realized. The walking speed was 7.68 s/step with a 0.1 m step length.

The authors are engaged in studies of biped walking robots from the following two viewpoints. One is a viewpoint as a human science. The other is a viewpoint towards the development of humanoid robots.
In the current research concerning a biped walking robot, there is no developed example of a life-size biped walking robot with the antagonistically driven joints by which the human musculoskeletal system is imitated in lower limbs. Humans are considered to exhibit walking behavior, both efficient and capable of flexibly coping with contact with the outside environment. However, developed biped walking robots can not realize the human walking. The human joint is driven by two or more antagonistic muscle groups. Humans can vary the joint stiffness, using nonlinear spring characteristics possessed by the muscle themselves. The function is an indispensable function for a humanoid.
Therefore, the authors designed and built an anthropomorphic biped walking robot having antagonistic driven joints. In this paper, the authors introduce the design method of the robot. The authors performed walking experiments with the robot. As a result, quasi-dynamic biped walking using antagonist driven joint was realized. The walking speed was 7.68 s/step with a 0.1 m step length.

This paper describes a humanoid robot "Hadaly," that was developed as a basic model for the final version of Humanoid. In this study, the authors feature an attempt to find the configurations and functions that are reguired for a humanoid. Hadaly consists of four systems; an audio-visual system, a head system, a speech system and an arm system. The configurations and functions reguired for a humanoid robot are clarified based on the results of the information assistance experiment with Hadaly.