This paper investigates the behavior changes observed in individuals utilizing a highly efficient three-hand body in VR with 3rd Hand equipped on left shoulder after motor skill training. The study focuses on spatial awareness and cooperative action and explores the implications for future research and augmentation body design. Participants underwent a six-round training program involving tasks to enhance their proficiency with the three-hand body. Pre- and post-training evaluations were conducted in two conditions: spatial awareness (C1) and cooperative action (C2). Results revealed distinct hand preferences and usage ranges. In C1, participants showed biases towards their respective hand positions, with improved decision-making between the left and third hands post-training. In C2, the third hand usage shifted towards the right side, indicating a preference for a partnership with the right hand and improved cooperative action between the hands. These findings provide insights into behavior changes and performance enhancements. Further research is needed to explore the impact of training on the natural body and potential sense of loss experienced by individuals. This study contributes to our understanding of human body perception and the optimization of motor skill training systems for augmentation bodies.

We propose multi-presence system for simulating multiple locations using multiple extended bodies. Generally, in the single presence, single-task state in which single extended body is operated, the higher the presence, the higher the performance. However, it has not been clarified if presence is effective for multitasking in multi-presence system. Thus, we examined the effect of presence from the perspective of working memory, which is cognitive characteristic required during multitasking. Specifically, we developed multi-presence system with four robots in virtual space under high- and low-presence conditions and performed multitasking tasks according to the working memory. The results showed that the multitasking performance was higher when sense of presence was high. Thus, we propose that an increase in sense of presence when designing multi-presence system can improve the efficiency of multitasking.

Body language is an essential component of communication. The amount of unspoken information it transmits during interpersonal interactions is an invaluable complement to simple speech and makes the process smoother and more sustainable. On the contrary, existing approaches to human–machine collaboration and communication are not as intuitive. This is an issue that needs to be addressed if we aim to continue using artificial intelligence and machines to increase our cognitive or even physical capabilities. In this study, we analyse the potential of an intuitive communication method between biological and artificial agents, based on machines understanding and learning the subtle unspoken and involuntary cues found in human motion during the interaction process. Our work was divided into two stages: the first, analysing whether a machine using these implicit cues would produce the same positive effect as when they are manifested in interpersonal communication; the second, evaluating whether a machine could identify the cues manifested in human motion and learn (through the use of Long-Short Term Memory Networks) to associate them with the appropriate command intended from its user. Promising results were gathered, showing an improved work performance and reduced cognitive load on the user side when relying on the proposed method, hinting to the potential of more intuitive, human to human inspired, communication methods in human–machine interaction.

This study proposes a method for finding a parasternal long-axis view in echocardiography autonomously with a robotic ultrasound (US) system. In obtaining this view, it is necessary to avoid the ribs and lungs because they reduce the clarity of US image. Meanwhile, the anatomical position and size of the heart, lungs, and ribs differ between individuals, which makes it difficult to find the optimal position of the US probe. Our proposed system is comprised of the following three processes. First, an exhaustive scan of the chest wall region is performed. The position of the probe that allows the mitral valve to be centrally positioned is estimated based on this scan. Second, the probe is rotated once in the yaw direction while being fixed in that position. The yaw angle is estimated at a point parallel to the left ventricular longitudinal axis in the acquired images. Finally, the pitch angle of the probe is estimated so that the probe avoids the connection between the mitral valve and the papillary muscle and chordae. To validate the proposed method, we performed human trials with five healthy subjects and measured the detection rate of observation points used to evaluate the image quality of parasternal long-axis view. The result showed that the median detection rate of the observation points was 63.3 ± 5.3%, which implies that the proposed method is valid.

UNLABELLED: Unilateral spatial neglect (USN) is defined as the inability to attend and see on one side, which seriously interferes with daily life. Clinically, patients with left USN commonly demonstrate a striking immediate capture of attention from ipsilesional, right-sided items as soon as a visual scene unfolds (i.e., magnetic attraction [MA]). Therefore, this preliminary study utilized a three-dimensional (3D) virtual environment to evaluate the effects of eliminating stimuli in the rightward space and directing attention to the left on neglect symptoms. METHODS: Seven patients with USN participated in this study, and two types of visual stimuli were created: the numbers and objects in the 3D virtual environment. To eliminate the visual stimuli on the right side, a moving slit was introduced in the virtual environment. During the experiment, patients were required to orally identify each object and number both in moving and nonmoving slit conditions. RESULTS: A statistical comparison of scores with and without the moving slit in the 3D virtual space indicated significant changes in the object stimuli condition; however, no statistically significant difference was observed in the number stimuli condition. CONCLUSIONS: Masking the right side within the 3D virtual space increased the number of objects that can be recognized on the left side by patients with USN. The results may allow interventions in a virtual reality environment that closely resembles the patient's real-life space.Clinical Relevance-Magnetic attraction is a symptom seen in patients in clinical practice, but there is no method of rehabilitation. The proposed moving slit method is expected to be effective because it enables attention guidance in a three-dimensional space.

When the robot arm is manipulated simultaneously with the natural body, it becomes multitasking, which places a significant burden on human cognitive abilities. We hypothesize that training that applies moderate attentional load in stages will expand the amount of effective attentional resource and improve multitasking ability. Therefore, we constructed two VR environments: a training stage to expand attentional resource by applying graded attentional load, and a test stage to evaluate the amount of attentional resource. We conducted several sets of training and evaluated the effective attentional resource in the test stage before and after the training, and compared the evaluations. The results suggested that training with graded attentional load can expand the effective attentional resources.

In recent years, research on augmented bodies that extend the capabilities of the human body has attracted much attention. Multi-presence, the topic of this paper, is one of the extended body studies, and is a system in which multiple extended bodies are operated by a single person. Until now, the role of presence in the parallel and multiple manipulation of extended bodies has not been clarified. From the validation test, subjective images with a high sense of presence were more likely to sustain residual attention associated with attention switching than overhead images with a low sense of presence, and task performance was improved. Thus, the results suggest the usefulness of increasing the sense of presence for each task when designing multi-presence.

Palpation is a noninvasive and quick medical procedure that can be used to estimate disease by directly touching the affected area. Palpation is a skill passed down from master to apprentice through experience, and quantification of palpation and its reproduction by an autonomous robot have not been realized. In this study, to define palpation movements, we interviewed dermatologists who frequently perform palpation in their medical practice, and measured / analyzed the posture and finger pressure during palpation. As a result, the palpation movements of physicians was classified into five types ( "rubbing," "pushing," "pinching," "rocking," and "kneading") based on differences in the trajectory of the fingertips and the affected area condition. Thus the requirement specifications to develop robot hand was achieved.

In this study., as a first step to establish a method to control the body posture by a robot to avoid the influence of the lungs., we quantitatively elucidated the relationship between the lung volume required to produce clear mitral valve echocardiographic images and body posture. Due to the air in the lungs., it has been difficult to obtain clear ultrasound images when using the echocardiography robot. To solve this problem, we focused on the fact that during manual examinations, physicians and technologists respond to the effects of the lungs by exhaling and changing body posture. The experimental findings showed that the lung volume monotonically increased as the roll angle was increased from 0° to 10°, 20°, and 30°, and that clear mitral valve ultrasound images could be obtained even when some air remained in the lungs. The relationship between the lung volume threshold and respiratory state was also examined. When the roll angle was 20° or greater, the lung volume threshold exceeded the resting expiratory level in all subjects, suggesting that clear mitral valve ultrasound images can be obtained by respiratory control within the range of resting respiration without forcing out breaths.

The detachable body is the extended concept of the Supernumerary Robotic limbs (SRL), which can detach and attach from the user's body to the environment. This concept enables collaboration and multi-presence. However, in the previous research, the discussion of the positional relationship between modular body components is still unclear regarding the user's work efficiency. Therefore, the experiments were conducted to observe the effect of detached arm position on the work efficiency for effective work using modular bodies like detachable bodies. The first experiment compares work efficiency(time to finish task and distance error) when the positional relationship between the robotics head and arm is kept the same during attached/detached. Secondly, the comparison of the position variations during detached was also investigated. As a result, the time to finish the task in the detached case is significantly higher than in the attached case, suggesting the advantage of the attached case. Also, the tendency indicates that work efficiency dropped in positions over 39 cm horizontally. The overall suggest revamping the system through depth recognition, motor training, and input scaling. Also, the result of the position's variations can be considered as a design parameter to design hardware that improves the usability of the modular body system.

Unmanned construction is a technology for operating construction machinery remotely to ensure safety of workers, for example for disaster site restoration. However, one of the most challenging problems with this technology is that the lack of visual information reduces its work efficiency to less than half that of manned construction. To ensure efficient work, it is necessary for the operators to properly plan the order of operations. While previous studies have analyzed planning skills in manned operations, only few studies have investigated planning skills in teleoperation. For planning skills in teleoperation, the additional element of human spatial cognition must be considered. Spatial cognition is the ability to grasp the work site three-dimensionally and accurately. This study aims to analyze the effect of the operator's spatial cognition on their planning skills in teleoperation. We measured the operator's spatial cognition and their planning skills on a simulator that reproduced the teleoperation of construction machineries. The results suggest that planning skills in teleoperation depend on the operator's spatial cognition. Furthermore, we proposed a support method for operators with low spatial cognition. To confirm the usefulness of the proposed method, an experiment was performed on a simulator that reproduced the teleoperation of construction machineries. The result indicates that the planning performance of the operator with low spatial cognition improved to the same level as that of the operator with high spatial cognition. Thus, the proposed method is expected to facilitate recognition of 3D space and to improve work efficiency of teleoperation for operators with low spatial cognition.

In the acute phase of stroke, it is important to promote functional recovery of the central nervous system by issuing motor intentions and performing repetitive movements. To facilitate early walking practice in the acute phase, we have developed what we term a 'supine pseudo-walking rehabilitation robot' that can perform walking training in the supine position. This robot is capable of multimodal feedbacks consisting of somatosensory feedback by following a walking trajectory, plantar vibration feedback that gives the sensation of load transfer during walking, and visual feedback in a virtual reality (VR) space. The somatosensory feedback is created by moving the patient's lower limbs in such a way as to reproduce the walking trajectory of a healthy subject, by means of a link mechanism. The feedback for plantar vibration, which gives the sensation of load transfer during walking, was generated by vibration motors which vibrate under first the heel and then the toe in accordance with the walking phase. We built a prototype of the supine pseudo-walking rehabilitation robot, and then evaluated whether it could produce the sensation of natural walking using these feedbacks by the experiments on healthy subjects, and found that it was possible to obtain the sensation of natural walking with the supine pseudo-walking robot alone. The results also suggest that the use of visual feedback and load-shifting sensory feedback can improve the sense of natural walking. In addition, when we evaluated how changes in muscular effort either appeared or did not appear when mismatch errors in different types of multimodal feedbacks were presented, a significant increase in EMG potentials was observed in two of the seven conditions. This suggests that it is possible to influence patient motor effort changes by manipulation of the multimodal feedback.

With the widespread adoption of Virtual Reality (VR) technology, VR devices can be more realistic and make the tasks they perform feel real to the user. It is this sense of realism that makes more and more people are using VR headsets. While using VR devices, the need to interact with the real world will also exist. For example, when people are using a VR headset to study and work, they have a physiological need (thirst, hunger, etc.), and need to interact with reality. But the closed nature of the VR headset causes this interaction to be very disruptive to the immersion of the user's current task. To address this issue, we propose an interaction method that combines an AI vision algorithm and a robotic arm to preserve immersion during task performance in VR. This method addresses the challenge of interacting with the real world while using closed VR devices. Our experiments show that our method outperforms see-through and mapping methods, allowing users to quickly re-immerse themselves after interruptions and reducing interruptions during real-world task performance. Future research will focus on improving this method without sensitization and expanding the range of real-world operations that can be performed.

It remains challenging for patients with stroke to regain the proper gait they had before stroke onset. In this study, one of the significant reasons for the problem is assumed to be the collapse of patients' internal model. Therefore, this study aimed to propose a method for lower-limb rehabilitation in the acute phase to prevent the collapse of the internal model and simultaneously promote voluntariness.To verify the effect of the proposed method and determine the optimal FB conditions, a supine pseudo-walking system has been developed providing multimodal sensory FBs, including somatosensory FB (walking on the walking robot), load transfer FB (plantar vibration provided by the robot), and visual FB (walking scene shown in virtual reality).First, the implicit error range of each sensory FB that was unable to recognize was investigated according to Weber's law. Subsequently, 12 participants were asked to perform 12 steps of walking exercise in the system to evaluate the unconscious motor-changing effect due to different/multimodal FBs. Errors were presented at the 7th step in either three FBs in the ratio determined or their combinations (two or three types of FBs simultaneously changing).Second, to examine whether the effect can last and influence the motion after the training, a pre-post comparison test was performed with the training in the middle, wherein implicit errors were presented in the three kinds of FBs.The results show that presenting implicit error can cause motor change, and multiple types of FBs may have a better effect. The statistical data of 12 participants of the pre-post comparison test show that the average integrated electromyogram in the post-test appears significantly larger than that in the pre-test. The result indicates that the motor-changing effect of the proposed method has a subsequent influence on motion and shows the possibility of the future application of the proposed method to the rehabilitation field.

In the present study, we used computational fluid dynamics to analyze the sag caused by spray painting, considering the change in paint shape due to flow. We focused on the paint adhering to the target surface because this behavior has not been previously examined. The particle method was adopted for the calculation because it enabled a stable analysis of the paint droplets and the complex uneven surface of the paint film. A high-speed camera and image analysis were used to capture the spray painting and identify the parameter values. Using the developed model, we analyzed the change in the film thickness distribution for painting on a flat plate in the vertical direction. It was confirmed that the numerical and experimental data correlated for two conditions of the target distance. In addition, we proposed a new index, Degree of Sagging (DSG), to evaluate the amount of sag based on the physical properties of the paint rheology and the geometry of the target. In the painting tests on flat plates with different angles, a strong positive correlation of 0.95 was observed between the sum of the calculated DSG values and the measured paint flow distance due to sag. In the painting tests on L-shaped surfaces, the predicted sag appearance by DSG agreed with the measured results at 14 of the 15 measurement points under all conditions. Overall, a computational model was developed for field implementation that could predict painting thickness distribution and sag occurrence. <italic>Note to Practitioners</italic>&#x2014;The present work is motivated by the problem that teaching painting robots in a painting site is particularly time consuming. To address this problem, off-line programming methods have been proposed to computationally predict paint quality and film thickness and determine the painting route. Conventional approaches have approximated the paint deposition model with a function, which determines the paint thickness distribution, or simulated this model with high accuracy by considering electrostatic forces and wind velocity fields using computational fluid dynamics (CFD) modeling methods. However, two major problems exist in the field implementation of these studies: The first problem is the inability to predict defects, including sagging, that may occur after painting. In the conventional approach, the behavior of the paint after it adheres to the target is outside the scope of the calculation. The second problem is the high computational resource cost of CFD simulation, which renders its application to robotic painting challenging. In painting sites, the painting thickness must be accurately predicted and routed in a short period of time. In this paper, we present a method for analyzing film thickness distributions by considering time series changes of flow and propose a function-based model for predicting sagging based on the simulation results. The model for sag prediction was shown to be computationally inexpensive enough to be implemented in the field. The results of several painting experiments with a real robot confirmed the validity of the predictions made by this method. Our method could be implemented in the near future as a prediction system for off-line evaluation of painting routes, which could significantly reduce teaching cost. Since the target in this paper was a flat plate, it is necessary to conduct evaluation tests using various target shapes and painting conditions. Also, integration with the painting route optimization method has not yet been achieved, which is a topic that will be addressed in the future.

This study developed a paint deposition model that considers the position and direction of the painting gun was developed. Therefore, we focused on changes in paint deposition due to changes in the painting angle, which had not been focused on before. The calculation method employed adds an angle-specific paint deposition model derived by multiple regression analysis to the conventional paint deposition model. To confirm the validity of the angle-specific paint deposition model, a painting test on an L-shaped surface was conducted, and the measured and predicted values were compared. The L-shaped surface is a typical shape that the film thickness distribution changes with angle. As a result, it was confirmed that the predicted values agreed well with the measured values in the L-shaped surface painting test, indicating the validity of this study.

Unmanned construction is a technology developed for disaster site restoration involving the remote operation of construction machinery, ensuring the safety of workers. However, currently available technology is only about 50% of the work efficiency of manned operation, thus a major goal is to approach the work efficiency furnished by manned operation in unmanned operation. To ensure efficient construction, environmental information must be obtained, and the order of operations must be properly planned before the start of construction. In addition, because visual information is an essential element of teleoperation, appropriate visual information should be presented to the workers, based on work states. However, it is not clear what images would be most useful or at what time. To clarify these issues, understanding what information is most important during operation, what information is most typically lost, and at what time is vital. Therefore, in this study, we propose a method to analyze the operator's cognitive map during operation, in an effort to extract the information most strongly considered by the operator and information that is most likely forgotten.

The purpose of this study is to determine the intervention method among individuals by analyzing and categorizing how the performance on a dual task decreases when the required attentional load increases through a validation test. The validation test consisted of a dual task with two different tasks. As a result of the validation test, we hypothesized that there exists a one-sided state in which response delays occur in the low-priority task during the transition from the dual-task state, where the task is performed stably, to the saturation state, where all tasks are disrupted. Therefore, considering the one-sided state, we classified participants' attention distribution state into four states during the dual-task and analyzed the transition of the collapse model for individual. As a result, we were able to identify the one-sided state, classify the collapse models of the dual-task into three patterns, and propose appropriate timing of intervention methods for each pattern.

In order for us to know if a research field that we know nothing about will suit us and if it will be worthwhile for us to devote ourselves to, the only thing we can do is to jump in and experience it. With this mindset, I have been able to pursue research in trans-disciplinary studies that are not restricted to existing boundaries and conduct pioneering research that applied my own specialty of robotics to medicine leading to a fusion of the two. I have studied humanoid robots at first. What especially interested me was the haptic sense, and I started research of sensory in Biomedical Engineering area. My basic stance in applying robots to the medical field is that humans should do most of the work with support from machines kept to a minimum. Even in Jizai research, the basic principle that humans are the masters and robots are the subjects does not change. The Jizai research examples that we are working on are the “Third Arm” and “detachable body” as a development of the Third Arm. In our laboratory, we are also promoting turning technology into businesses. It is important for researchers to envision technology that will bring innovation to specific purposes. Two concepts that I am emphasizing recently are design thinking and vision-oriented thinking. One other thing that I work on as one who is affiliated with a university is the development of researchers. I believe it is important for us to have two or more axes in both research and in our daily lives. In research, in addition to your research theme as part of a project, you should have your own research theme. One of the keys to concurrently succeeding at multiple jobs is to cooperate with your colleagues.

Body language is an essential component of communication. The amount of unspoken information it transmits during interpersonal interactions is an invaluable complement to simple speech and makes the process smoother and more sustainable. On the contrary, existing approaches to human-robot collaboration and communication are not as intuitive, especially when it comes to robots transmitting information to their users. This is an issue that needs to be addressed if we aim to continue using artificial intelligence and machines to increase our capabilities, or as collaboration partners. The purpose of this study was to analyze the concept of a machine communicating with its user in a manner that closely relates to how humans communicate during collaborative work, using the Japanese rice cake making process as an example. First, the elements necessary to achieve the synchrony of individuals participating in the rice cake making process were clarified. Then, the same elements were reproduced in a simulated environment and applied to a rice cake making situation, this time requiring a collaboration between an individual and a robot. In this seccond step, the robot was made to mimick some key inter-personnal implicit communication elements discovered during the first stage of the study. Results showed an improvement in performance, along with a better capacity to predict and adapt motion according to the other party's, suggesting that the system was capable of assisting in realizing a certain level of understanding between biological and artificial agents for collaborative work without any form of explicit communication.

Many everyday tasks, like walking down a street, require us to dual task to also avoid collisions of our swinging arms with other pedestrians. The collision avoidance is possible with ease because humans attend to all our (embodied) limbs. But how does the level of embodiment affect attention distribution, and consequently task performance in dual tasks? Here we examined this question with a dual task that required participants to perform a cued button-press (main task) with their right hand, while reacting to possible collisions by a moving object with a left ‘robot’ hand (secondary task). We observed that participants consistently improve main task performance when they perceived the robot hand to be embodied, compared to when they don’t. The secondary task performance could be maintained in both cases. Our results suggest that embodiment of a limb modifies attention allotment for the benefit of dual motor task performance using limbs.

The effectiveness of sensory substitution technology, such as haptic-based vibrotactile biofeedback (VBF), has been verified for balance training and rehabilitation. However, whether VBF training changes postural dynamics in older people remains unknown. This study investigated the influence of VBF training on postural dynamics during single-leg standing in older adults, using detrended fluctuation analysis (DFA). Twenty older adults participated in this study. Measurement of postural sway comprised three phases: first measurement session as a baseline test, postural training (day 1), and second measurement session (day 2). The BF group received BF training during the balance training session, while the control group practiced single-leg stance without BF. The center of pressure (CoP) trajectory was recorded in the first measurement session (pre) and second measurement session (post) at 50 Hz. DFA revealed the presence of two linear scaling regions in the CoP, indicating the presence of fast- and slow-scale fluctuations. For the BF group, slow-scale postural dynamics revealed more anti-persistent behavior after training in the anterior-posterior direction. However, the control group showed a change toward more random dynamics after training. These different influences suggest that the BF system might improve error correction strategies during single-leg standing for older adults, while single-leg standing training without the BF system might cause the loss of controllability in single-leg standing. Further, the results of the DFA are discussed in the context of balance training using VBF.

Recently, fluctuations in the cost of labor and prices of natural resources have increased the difficulty of the business environment for mine development. Therefore, it is necessary to improve excavation efficiency using hydraulic excavators. Getting the actual excavation resistance for efficient excavation is challenging. To obtain lower resistance in excavation, we aimed to design a Discrete Element Method (DEM) parameter identification system that can calculate excavation resistance. To validate two calculation models in this system, we used a robot arm, different excavation objects, and a DEM software to compare the resistance between the actual excavation and the simulation. We selected the calculation model more approximate to the actual excavation resistance. Thus, our experiments could prove data similarities between simulation and actual excavation. However, a part of excavation resistance is still not approximated in simulation. Therefore, we conducted experiments using steel balls to identify the relationship between the physical properties of excavation objects and the calculated resistance. We obtained conclusions on making calculated resistance more approximate to actual excavation resistance by adjusting the properties

<jats:p>Over the last few years, numerous robotic ankle-foot orthoses have been developed to help stroke patients optimize gait rehabilitation. In this paper, we present a study on the effects of assistance on dorsiflexion-restricted gait. Our high-dorsiflexion assistive system aims to provide full assistance to realize passive training of dorsiflexion during the swing phase and prevent compensatory movements. This system, which includes a McKibben-type artificial muscle and an air source, is lightweight and provides a high-dorsiflexion torque. The device could help boost overground gait rehabilitation in stroke patients. With this system, we conducted an experiment on five healthy participants whose dorsiflexion movements were restricted, and the extent of their compensatory movements differed. The results of the processed surface electromyography data differed significantly when dorsiflexion movement was assisted by our system. The spatial parameters also showed significantly improved compensatory movement inclination with sufficient assistance. These results indicate the potential of our system to assist in passive training of ankle dorsiflexion movements and to prevent incorrect gait in patients with low dorsiflexion abilities.</jats:p>

Haptic Feedback Belt is the device which notice the supernumerary arm’s posture which is put on the arm’s user as vibration feedback. In this paper, we examine whether participants can perceive the supernumerary arm’s posture which leaves them with Haptic Feedback Belt on Dual task. Experiment was conducted to compare perception accuracy when they accomplished the recognizing task of supernumerary arm’s posture on Single task situation and Dual task situation. On Single task situation, they accomplished only the recognizing task. Then, on Dual task situation, they accomplished the recognizing task with pouring water into beakers with their own body. The results suggested that they can perceive the posture on Dual task situation as exactly as on Single task situation.

During the drying process of paints, the solvent contained in the paint volatilizes and the film thickness decreases. Since this property is highly dependent on the drying temperature and can affect the quality of the paint, appropriate temperature conditions and film thickness control are required. In this study, a model based on mass transfer theory was developed to calculate the paint film thickness at an arbitrary elapsed time. As a validation test, wet film thickness was measured by a non-contact film thickness gauge and compared with the analytical results. As a result, accurate paint film thickness prediction was achieved by setting appropriate parameters for different drying conditions.

One of the main sequelae of stroke is difficulty walking, which is characterised by decreased walking speed and asymmetrical walking patterns. Physical therapists often rely on explicit motor learning strategies, i.e., providing mainly verbal instructions for how movements should be performed. However, the voluntary movement induced by explicit instruction may lead to associated unintended muscle contractions or higher cognitive demand, which could be detrimental. We introduce a vibrotactile cueing device that implicitly improves walking speed. The stroke patient walks while alternating vibrational cues are given to the left and right sides of their waist. At each specified step, cueing frequency increases in the cueing group without the patient’s awareness. The four patients in the cueing group did not notice the increase in walking speed during training; however, we observed an improvement in walking speed and cadence in patients using the proposed cueing system, which was maintained during the posttest phase. Additionally, patients using the cueing system were able to suppress excessive compensatory movements during training compared with patients who did not use the system. This case series study indicates that the proposed system for gait rehabilitation of stroke patients can enable an increase in walking speed without excessive effort.

This paper discusses methods to manipulate an extra limb at the same time as the user's body parts. Two types of extra limb manipulation methods exist: path instruction, which involves continuous input such the master-slave method, and point instruction, which only involves commands of the coordinates of the required transit points. Intuitively, point instruction is considered to be easier to use for simultaneous operations because the attention time per instruction is shorter. In contrast, from a cognitive science perspective, depending on the amount of attention switching involved during the tasks and the attention level required for each task, it may be easier to perform dual tasks with path instruction than with point instruction. Therefore, we conducted a user study to compare the feasibility of using point instruction and path instruction in tasks that require considerable attention switching and tasks that do not as well as tasks that require a high level of attention for execution and tasks that do not. The results showed that point instruction improved work efficiency in all task conditions, but path instruction improved work efficiency only when the task was easy to perform. These results suggest the superiority of point instruction and also indicates that the need for intermittent attention allocation, such as the time and frequency of each session, should be further discussed.

This paper proposed a design of a detachable robotic head that can imitate human motion in a remote environment. Firstly, the biomechanics of the human body parts related to human vision are studied: neck and waist. After that, the design parameters are extracted from the neck and waist as the design requirement. Then, the mechanical design of the detachable robotic head is split into three parts: neck, waist, and detachable mechanism. The gear differential mechanism is used further to develop the motion range of the proposed design. Consequently, a prototype is made from a 3d-printed part to test the functionality of the design. The evaluations are separated into three sections. First, the range of motion shows that the proposed design can guarantee the human motion range and provide more motion range in the remote environment. Secondly, the frequency response shows that the detachable head can handle the natural headshaking motion of the human at 1.5 Hz in horizontal and 2 Hz vertical head shaking. However, both do not reach the vigorous voluntary headshaking. Also, the maximum latency between the user and the robot is 25 ms, which is low enough for human perception. Last, the angular error between the user and the robot is tested in trackability. As a result, the error is less than 1.6 degrees, and this means the proposed design can imitate human head motion without feeling dislocated.

Unmanned construction technology is being developed to aid in disaster recovery by remotely operating construction machinery, thereby reducing the possibility of secondary disasters. However, the work efficiency of unmanned operation is only about half that of the normal operation. Thus, various support methods based on operation states have been developed to improve the work efficiency. It is important to automatically determine the operation state of the construction machinery to apply these support methods. In this paper, we propose an extended operation state identification model that can identify various operation states. The proposed model consists of two parts: operation state classification system using the classification model of Long Short-Term Memory (LSTM), and novel state search and registration system using the regression model of LSTM. Simulation of unmanned construction was conducted to verify the potential of the proposed model.

The increasingly aging population in Japan, has given rise to a shortage of caregiver availability. By the year 2025, it is projected that there will be a need for 380,000 caregivers. One of Caregivers' compulsory tasks consists in checking diapers every 2 hours both during the day and at night. It becomes even more burdensome when they must also do this around or after midnight, depriving them of quality sleep. The use of excretion detector devices may provide a solution to this problem. However, there are sanitary limitations to the recovery and reuse of such devices. Additionally, there is obvious discomfort that comes with attaching a large device to a diaper. To address this challenge, the disposability, and ultra-thinness of the device presented in this study are paramount. We developed and evaluated disposable film-based urine detector devices for caregivers use.

Unilateral spatial neglect (USN) is defined as impaired attention to sensory stimuli on one side, which can exist for near and far spaces combined or independently. Thus, quantifying both near- and far-space neglect is crucial. This study aims to propose an index to quantify the near/far spatial neglect ratio to describe the USN symptoms' characteristics in each patient using immersive virtual reality (VR) technology. An object-detecting task was performed for five USN patients in a three-dimensional VR space. The examiner recorded the positional data of the objects that were recognized by the USN patient using coordinate data. The near/far ratio (NFRatio) was calculated using the proposed equation to quantify the difference in neglect severity in near and far spaces of each patient. Among the patients, four tended to have greater far-space neglect, and one tended to have greater near-space neglect. Moreover, the near/far spatial neglect ratio was shown to vary according to height. This is the first study to propose immersive VR to quantify the near and far spatial neglect. However, further study is needed to assess its reliability and validity and describe its clinical usability. Clinical Relevance - In clinical practice USN symptoms cause neglected symptoms in 3D space so the proposed system will be of high clinical significance if 3D assessment is realized

Unilateral spatial neglect (USN) is the failure to report, respond, or orient to novel or meaningful stimuli presented on the side opposite a brain lesion. In our previous study, we reported that the ability of patients with USN to perform when the neck was fixed (called cognitive ability) was different from that when the neck was not fixed (called exploratory ability). However, the exploratory ability index has not been clarified, and cognitive and exploratory abilities have not been quantified. Thus, in this study, we identified neck movement as an exploratory ability index for patients with USN. Furthermore, we proposed equations to quantify cognitive and exploratory abilities and suggested that these equations can be used to understand patients' neglect symptoms in more detail. These findings revealed that the two evaluations of cognitive and exploratory abilities are crucial in USN evaluation and are key to individualizing intervention for each patient.

Here, the thickness distribution of a spray-painted film was analyzed by computational fluid dynamics, considering the change in the paint shape due to flow. We focused on the paint adhering to the target because this behavior has not been previously examined. The particle method was adopted for the calculation because it enabled a stable analysis of the paint droplets and the complex uneven surface of the coating film. A high-speed camera and image analysis were used to capture the spray painting and identify the values of the parameters. Using the developed model, we analyzed the change in the film thickness distribution for the scene of painting on a flat plate in the vertical direction. It was confirmed that the numerical and experimental data correlated for two conditions of the target distance.

The term 'esports' is used to refer to game-based competitions considered as sports events. Esports currently involves a qualitative instruction that relies on individual experience and intuition, such as instruction from professional gamers. By contrast, sports observe a shift from qualitative to high-quality instruction using quantitative evaluation indices. Therefore, in esports, evaluation indices must be quantified to improve the training quality. This study focuses on crossing situations in soccer games. Crossing is a play in which a player passes from the side to the goal. It is important in soccer because of its high possibility of leading to a goal. Therefore, the quality of cross training in soccer must be improved to increase the scoring probability by crossing. As a feasibility study, this work aims at a quantitative evaluation of crossing in soccer games. The important factors for a successful cross are the positional relationship and the speed of each player at the time of the cross. A crossing scene is modeled to obtain a cross score based on these factors. First, when the velocity and trajectory of the cross ball are determined, the area is defined in which the offensive and defensive players can touch the ball. This area is calculated, and the value of how close to the center the ball trajectory passes in relation to the area is determined for each player. Using these values, the Cross Score (CS) was obtained by constructing a cross evaluation formula. To confirm the validity of the obtained evaluation values, a system that can obtain the evaluation values using image processing was developed. Then, 264 videos of crossing scenes in a soccer game were obtained, and CS was calculated for each of them. The correlation coefficient between the cross score and the percentage of successful crosses is 0.923, showing a strong correlation and confirming CS validity. As an example of application of the CS, it is possible to judge whether a cross is good or bad by displaying the CS on a heatmap using quantitative values. This enables visual and quantitative feedback using CS, suggesting the possibility of improving the quality of training.

Unilateral spatial neglect (USN) is a higher cognitive dysfunction that can occur after a stroke. It is defined as an impairment in finding, reporting, reacting to, and directing to stimuli presented opposite to the damaged side of the brain. So far, we have developed an immersive virtual reality system that releases the attention biased to the non-neglected side and guides it to the neglected side to improve the symptoms of neglect. However, it improved neglect symptoms evaluated using a paper-and-pencil test on a desk (i.e., Behavioral Inattention Test), and it did not improve neglect in daily life evaluated using a standardized evaluation tool [i.e., Catherine Bergego Scale (CBS)], which is a rating index of neglect in actual daily life. Therefore, establishing a method for improving neglect in daily life is necessary. This study was designed to develop a platform for improving neglect in daily life as an initial investigation of rehabilitation methods for patients with USN. To improve neglect, the following three elements were derived from previous studies that should be included in rehabilitation: object search by moving around, reproduction of the complexity of daily life, and own body movement in the neglected side with visual confirmation. The patient moves around the room and visually explores and touches the objects presented in the mixed reality (MR) space. Using this system, we conducted a validity test on a patient with USN. The results showed that the patient improved from moderate to mild neglect in the CBS. Thus, the applicability of proposed MR system was suggested in terms of improving neglect in patients with USN in daily life environment.

This paper introduces a system designed to support conducting experiments of subjects when the situation does not allow experimenter and subject to be in the same place such as the COVID19 pandemic where everyone relied on video conference applications which has its limitation. Due to the difficulty of directing with a video conferencing system using solely video and voice. The system we developed allows an experimenter to actively watch and interact with the subject. Even if you're operating from a distant area, it is still possible to conduct experiments. Another important aspect this study will focus on is the case of when there are several subjects required and the experimenter must be able to guide both subjects equally well. The system proposed uses a 6 DoF robotic arm with a camera and a laser pointer attached to it on the subject side. The experimenter uses a head-mounted display to control it and it moves corresponding to the head movement allowing for easy instruction and intervention to the subject side. Comparison with other similar research is also covered. The study will focus mainly on which viewing method is the easiest for the experimenter to use, and if teaching one subject at the time gives better results than teaching two subjects simultaneously.

Computed Tomography (CT)-guided intervention requires an expertized skill to physicians and a numerous of robot-assisted needle insertion system has been developed. As a challenging issue developing the CT-guided needle insertion robot system, the inside of a CT gantry is a special environment where there is no room for movement and no metal can be inserted because of causing an artifact on the acquired image. The gantry entry portion of the robot therefore requires miniaturization and non-metallization. The most difficult part of the non-metallization of a robot is the motor element. While many of the robot's structural materials can be made non-metallic thanks to advances in plastic materials, the actuator cannot be made non-metallic. In some cases, the actuator can be attached directly to the moving part, but this limits the angle of motion of the robot to where the actuator is outside the imaging range. In this report, we introduce a unique mechanism that enables the needle manipulation with a miniaturized configuration inside the CT gantry. The mechanism satisfies the requirements of power transmission between axes whose relative positions are indeterminate, miniaturization to prevent interference with robot motion, and non-metallization. This mechanism combines a single-node link and gears to transmit rotational power while passively responding to changes in the positional relationship between axes. The hinge fixation of the basic single-node link is aligned with the axis of rotation of the first gear, and the subsequent gears can be freely arranged to mesh with each other. The minimum configuration is 3 gears, one at the hinge, and two at each end. Theoretically, the number of gears can be increased, but it is desirable to use as few gears as possible because transmission accuracy will decrease due to backlash and other factors. The movement of the mechanism does not necessarily affect the state of the gears at all. If the absolute angle of the linkage changes, the positional relationship between adjacent gears changes while the distance between the axes remains constant. If the positional relationship of the meshing gears changes, the gear will rotate. If rotation is simply transmitted, this angular change does not affect the operation of the machine, but if rotation is transmitted for the purpose of angle determination, the angle input side must be adjusted. This depends on the changing tip position coordinates. Therefore, we developed an algorithm that outputs adjustment parameters upon input of information on the mechanism to be used. The algorithm derives an approximate equation from numerical analyses that limits the error from backlash. We applied this mechanism to our robot with a 25G needle and inserted the needle into the target from various angles. The accuracy was 2.5 mm, which satisfied our requirements.

In recent years, the spread of infectious diseases, such as COVID-19, has increased the need for medical examinations to avoid contact between doctors and patients. Most treatments, especially dermatology, require palpation, and its impact is significant. In this study, we aimed to reproduce the judgment of the softness and surface textures of diseased parts, which is important to dermatologists for determining the condition, using a simple robot device. Five levels of softness and three types of surface textures labeled with 14 types of materials were obtained from interviews with dermatologists. To acquire a haptic response from materials during pushing, 1) a single-rod probe with a haptic sensor using a linear actuator and 2) a dual-rod type configuration to obtain vibration propagation was constructed. Frequency-analyzed images were produced from the obtained waveforms of force and acceleration. A total of 343 images from 13 materials were used for transfer learning and were classified using AlexNet. The classification accuracy of the single-rod probe was 93.0%, and that of the dual-probe configuration was 95.2%. The classification accuracy was improved using the dual probe configuration than the single one; the softness classification accuracy was improved from 93.8% (single-rod) to 95.7% (dual-rod configuration). The surface texture classification accuracy was improved from 91.9% (single-rod) to 92.8% (dual-rod configuration), respectively. Therefore, the proposed method enables the reproduction of the judgment of five-level softness and three types of surface texture judgment by dermatologists.

When using a supernumerary limb, it is necessary to pay appropriate attention to the supernumerary limb and recognize its state. In this study, we verified whether the posture of a supernumerary limb removed from a human and placed in an environment could be perceived from the tactile feedback in a dual-task. Then, we examined the effect of perceivability on dual-task performance. In the former verification, participants were asked to answer the position of a randomly stopped supernumerary limb while pouring a prescribed volume of water with their natural bodies. The latter was examined with 2 kinds of dual-tasks. Dual-task A required the tasks on the natural body and the supernumerary limb sides to have a common perceptual modality. Dual-task B did not require the tasks on the natural body and supernumerary limb sides to have a common perceptual modality. Thus, supernumerary limb location identification accuracy was as good in dual-task conditions as in single-task conditions. In addition, task performance in dual-task B was improved by the presence of tactile feedback.

Post stroke patients may suffer from a gait disorder which is called foot drop. They may experience a toedrag, slow walking speed and a high risk of tripping. Although physical therapy exercises can be a remedy to such cases, their high cost and the lack of professional caregivers arise the need for robotic rehabilitation systems. On the other hand, the existing robotic systems for foot-drop rehabilitation are heavy and bulky. Therefore, in this paper, a lightweight foot-drop rehabilitation system based on a wire-driven redundant spherical parallel manipulator (RSPM) is developed. The proposed RSPM can provide 3-DOF movements to exercise the dorsiflexion, plantarflexion, supination, lateral and medial rotations. Kinematic and static analyses are performed for the proposed rob RSPM. In order to guarantee permissible positive tensions for the wires of the RSPM, a new performance index is introduced, called permissible tension index. Optimum design based on optimizing certain performance indices is carried out to obtain the proper dimensions of the movable platform design parameters of the proposed RSPM. A new index called permissible tension index is introduced to guarantee permissible positive tensions for the wires of the RSPM. A weighted sum of the global kinematic dexterity, global minimized transmission and the global permissible tension indices is considered for the objective function of the optimization process. The RSPM performance is evaluated over its range of motion and the reaction forces exerted on the ankle are shown to be tolerable by an injured ankle. Additionally, the Jacobian-based kinematic controller is shown to be capable of tracking the normal gait trajectories with acceptable tracking errors.

This article explores a scheme of tuning a basic input-output (I/O) gain (BIOG) depending on usage conditions for improving the work performance of human-operated machines. I/O gain tuning is effective for improving operability and workability, but continual and/or huge changes makes operators confuse the machine dynamics, and then degrade the operability. Thus, the proposed tuning system tunes the BIOG at long terms according to comprehensive characteristics of the work content and operator, collected from a control lever input histogram. The target value is specified by a Gaussian distribution, meaning that all ranges of the spring-type control lever are equally used. This approach was chosen because leveling the control lever histogram independently of the operator and work content provides a consistent operational experience, leading to comfortable operations. In this article, BIOG curves are specified as a polygonal line involving a break and saturation point. These points are adjusted by reciprocal conversion of differential areas between the Gaussian distribution and obtained histogram curves. Experimental results obtained with a robot arm indicated that the developed BIOG tuning system could improve time efficiency by decreasing the differential area and increase the subjective usability as compared to a conventional fixed BIOG system. Moreover, the relationship between the histogram and BIOG curve could reveal features of both the work content and the operator's skill level.

In stroke patients, sensory loss often reduces the sensation of ground contact, which impairs motor learning during rehabilitation. In our previous study, we proposed a vibro-tactile biofeedback system (which we called the perception-empathy biofeedback system) for gait rehabilitation. The results of our 9-week pilot clinical test suggested that patients who had reached the autonomous phase in gait learning had difficulty noticing the external vibratory feedback provided by the biofeedback system, leading to ineffective intervention. We considered the possibility that slower walking speed might return the patient to the association phase and allow patients to improve their gait according to the sensory feedback provided. Thus, in this research, a method based on reducing walking speed to guide patients' attention was derived. A pilot clinical trial shows that there is a statistically significant increase of ankle dorsiflexion in the initial contact phase and increase of ankle plantarflexion in the push-off phase after vibro-tactile biofeedback system intervention with speed reduction, compared to intervention without speed reduction. The results suggest that, by reducing their walking speed during intervention, patients return to the association phase and recognize external vibratory feedback, which may result in better intervention effects.Clinical Relevance-This study provides knowledge about the optimal walking speed when using vibro-tactile biofeedback for motor learning in stroke patients.

This paper introduces a novel interface ‘3D head pointer’ for the
operation of a wearable robotic arm in 3D space. The developed system is
intended to assist its user in the execution of routine tasks while
operating a robotic arm. Previous studies have demonstrated the difficulty a
user faces in simultaneously controlling a robotic arm and their own hands.
The proposed method combines a head-based pointing device and voice
recognition to manipulate the position and orientation as well as to switch
between these two modes. In a virtual reality environment, the position
instructions of the proposed system and its usefulness were evaluated by
measuring the accuracy of the instructions and the time required using a
fully immersive head-mounted display (HMD). In addition, the entire system,
including posture instructions with two switching methods (voice recognition
and head gestures), was evaluated using an optical transparent HMD. The
obtained results displayed an accuracy of 1.25 cm and 3.56° with the 20-s
time span necessary for communicating an instruction. These results
demonstrate that voice recognition is a more effective switching method than
head gestures.

Since it is challenging to perceive space and objects with a video conferencing system, which communicates using only video and audio, there are difficulties in testing subjects in the COVID-19 pandemic. We propose the EASY-LAB system that allows an experimenter to perform observation and physical interaction with the subject even from a remote location actively. The proposed system displays the camera image on a HMD worn by the experimenter, which camera is mounted on a small 6 DOF robot arm end, allowing observation from an easy-to-see perspective. The experimenter can also instruct the subject using another robot arm with a laser pointer. The robot's joint angles are calculated by Inverse Kinematics from the experimenter's head movements, then reflected in the actual robot. Photon Unity Networking component was used for the synchronization process with remote locations. These devices are affordable, effortless to set up, and can be delivered to the subject's home. Finally, the proposed system was evaluated by four subjects, As a preliminary result, the mean pointing error was 1.1 cm, and the operation time was reduced by 60% compared with the conventional video conferencing system. This result indicated the EASY-LAB's capability, at least in tasks that require pointing and observation from various angles. The statistical study with more subjects will be conducted in the follow-up study.

This research proposes a concept of the "ubiquitous body system", a new concept of using multiple body parts at various places simultaneously. This system enables users to access any number of the bodies at a time, and make physical intervention to any locations regardless of the current location where user's natural body is. However, when the number of ubiquitous bodies becomes larger, it becomes more difficult to see or manage all of those tasks. In this short paper, we focused on the effect of spatial arrangement of the vision information on managing multiple tasks. We developed a vision presenting system in which the environment images of each ubiquitous body are arranged in the same way as the positional relationships of ubiquitous bodies in the real world. The result of a case study regarding usability of this prototype suggested that presenting visual information with same spatial relationships as real would be effective to switch user's attention and manage multiple tasks.

One of the problems with unmanned construction is the lack of visual information, which reduces work efficiency to less than half of that in onboard operation. Therefore, methods to provide visual information using drones and image processing were studied in the past. However, the addition of information causes the operator to fall into cognitive tunneling in which the attention is focused only on a specific image. In this study, we attempted to develop a method that can prevent cognitive tunneling and shift the operator attention to an appropriate view according to the working state of heavy machinery. Cognitive tunneling is caused by low visual momentum (which represents ease in information integration between views) and high visual saliency (which represents ease in attention). Therefore, because visual momentum can be improved by presenting the same landmark in different camera images, useful landmarks for each work state were included in each image. In addition, because humans tend to pay attention to objects that vibrate in the useful field of view, we presented the image of an external camera in the useful field of view and allowed the image to vibrate when the work state was switched. To investigate the effectiveness of the proposed method, an experiment was conducted on an actual hydraulic excavator. Although the proposed method did not improve the work efficiency of some operators, we believed that the proposed interface could direct the eyes of the operator to an appropriate image according to the work state.

In previous research, we found that modulating the assistance timing of dorsiflexion may affect a user's voluntary efforts. This could constitute a focus area based on assistive strategies that could be developed to foster patients' voluntary efforts. In this present study, we conducted an experiment to verify the effects of ankle dorsiflexion assistance under different timings using a high-dorsiflexion assistive system. Nine healthy and young participants wore a dorsiflexion-restrictive device that enabled them to use circumduction or steppage gaits. On the basis of the transition from the stance to the swing phase of the gait, the assistance timings of the high-dorsiflexion assistive system were set to have delays, which ranged from 0 to 300 ms. The index results from eight out of nine participants evaluated compensatory movements and revealed positive strong/moderate correlations with assistance delay times (r = 0.627-0.965, p <.001), whereas the other participants also performed compensatory movement when dorsiflexion assistance timing was late. Meanwhile, the results from tibialis anterior surface electromyography from six out of nine participants showed positive strong/moderate correlations with dorsiflexion assistance delay times (r = 0.598-0.922, p <.001), indicating that tuning the assistance timing did foster these participants' voluntary dorsiflexion movements. This result indicates that there should be a trade-off between ensuring voluntary dorsiflexion movements and preventing incorrect gait patterns at different assistance timings. The findings of this feasibility study indicate the potential of developing an adaptive control method to ensure voluntary efforts during robot-assisted gait rehabilitation based on assistance timing modification. A new assistance mechanism should also be required to stimulate and motivate a patient's voluntary efforts and should reinforce the effects of active gait rehabilitation.

One of the main sequelae of stroke is dificulty walking, which is characterized by a decreased gait velocity and asymmetrical walking patterns. The purpose of this research was initially focused on developing a vibro-tactile cueing device that recognizes an implicit increase in cadence frequency. Subsequently, a proof-of-concept study with patients who had experienced stroke was conducted to examine the applicability of the system that had been developed. We applied Weber’s law to provide an implicit method for increasing cueing frequency. This law involves the calculation of just-noticeable difference (JND) relative to a previous state. Throughout training with the proposed cueing device, patients marginally increased cadence, and their cadence and gait speeds were significantly increased post-test. Hip circumduction gait (i.e., abnormal gait patterns) did not change significantly throughout training. Notably, patients reported that they were unaware of any changes associated with the vibration stimulus. Our result demonstrates the immediate changes to cadence and gait speed that occurred through training with the proposed implicit cueing device. However, the result of this study is confined to immediate gait changes after training and utilized only a small sample of stroke patients. Thus, the limited volume of data obtained prevents rigorous analysis regarding the applicability of this training method. Nonetheless, these results are promising and provide a starting point from which to base larger studies.

Background: Fine needle insertion in the lower abdomen is difficult because of complex deflections and few image feedbacks. We aim to develop an approach for generating a straight insertion path by minimizing the needle deflection robustly based on a preoperative computer tomography (CT) image. Method: This study presents two approaches: an insertion control strategy that performs both vibration and rotation-assisted needle insertions and a preoperative insertion path planning for determining an optimal insertion path based on insertion angles at each tissue boundary. Those proposed approaches were evaluated through an in vivo experiment with a Landrace mini-pig. We compered the following: (1) the deflection with and without the insertion control strategy in different 10 insertion paths and (2) the score calculated by the path planning and the actual deflection in the 10 insertion paths. Results: The result shows that the deflection can be reduced significantly by applying the insertion control strategy in the optimal insertion path calculated by the path planning. Conclusion: The proposed method can decrease fine needle deflections in the lower abdomen, which has the potential for accurate and safety procedures without real-time CT imaging.

Work efficiency of unmanned construction is 40% lower than that of on-board operation because of lack of visual information. Despite previous researches to acquire external views using drones and image processing, finding out optimum and allowable camera placements on actual construction machinery for chosen scenario and machine has been difficult. This work therefore documents the derivation of optimum and allowable camera placements with skilled subjects and using an actual construction machinery for digging and releasing tasks. The experimental results indicate an optimum pan angle of 90 degrees, allowable pan angles of 60 degrees-90 degrees and allowable tilt angles of > 45 degrees during digging, and allowable pan angles of 45 degrees-135 degrees, an optimum tilt angle of 90 degrees, and al-lowable tilt angles of 60 degrees-90 degrees during releasing. These results can be referred to the camera placements for unmanned construction sites to improve work efficiency. We will derive the camera placements for other scenarios.

The increasing number of patients with hand disabilities after strokes or peripheral nerve injuries necessitates the continuous development of rehabilitation system devices to accelerate muscle recovery and to help patients regain the motor functions of their hands. This paper introduces the design of a hand rehabilitation system for patients who have a solitary impairment of their hand extension. The system was designed to be portable, simple, and cheap. Using a system based on a cable-driven mechanism instead of traditional rigid links reduces the degrees of freedom of the finger to one. The dielectric elastomer actuator was designed and fabricated as a smart actuator for the system, which supports the low cost of the system. A kinematic analysis of the cabledriven mechanism has been done. Parameters of the actuator were optimized to reach the required output. In order to characterize the performance of the actuator, a uniaxial tension test, isotonic test, and isometric test have been implemented.

Unilateral spatial neglect (USN) is a higher cognitive dysfunction that can occur after a stroke. It is defined as an impairment in finding, reporting, reacting to, and directing stimuli opposite the damaged side of the brain. We have proposed a system to identify neglected regions in USN patients in three dimensions using three-dimensional virtual reality. The objectives of this study are twofold: first, to propose a system for numerically identifying the neglected regions using an object detection task in a virtual space, and second, to compare the neglected regions during object detection when the patient's neck is immobilized ('fixed-neck' condition) versus when the neck can be freely moved to search ('free-neck' condition). We performed the test using an immersive virtual reality system, once with the patient's neck fixed and once with the patient's neck free to move. Comparing the results of the study in two patients, we found that the neglected areas were similar in the fixed-neck condition. However, in the free-neck condition, one patient's neglect improved while the other patient's neglect worsened. These results suggest that exploratory ability affects the symptoms of USN and is crucial for clinical evaluation of USN patients.

Hand-eye coordination (HEC) is an important ability in a variety of sports, as it involves the ability to quickly and accurately control motion using visual information. This ability is extensively involved in badminton smash reception. In existing studies on HEC evaluation, this ability was evaluated according to information collected after the motion had been performed. Accordingly, it is impossible to determine the specific phase of perception or motion that causes problems in HEC. The purpose of this study was to develop a system for identifying the abilities of perception involved in HEC as it relates to badminton smash it is considered as badminton's most effective shot. Two systems were developed to identify HEC perceptual abilities, one focused on perception in a static state (i) and the other focused on perception-to-motion comprehensiveness (ii). Next, two types of tests were conducted, one involving (i) and the other using (ii). The tests were randomly administered for a total of 18 participants in three groups: six people who had previously played badminton, six people who had played ball sports other than badminton, and six people who were inexperienced at ball sports. Participants were healthy adults. The tests aimed to identify factors of perceptual ability by comparing them across systems. The results showed no significant difference between experienced badminton players and others according to the conducted tests, where test (i) was used for measuring the distance between the shuttlecock and gaze. A significant difference between the group of experienced badminton players and the other two groups was, however, observed in the test using (ii). The results suggested the ability to follow the shuttlecock with the eyes to be a perceptual ability related to HEC in badminton smash receptions. The results of this study can help evaluate perceptual ability during smash receptions.

One of the most important problems in teleoperation of heavy machinery is that the work efficiency of teleoperation is lower than half that of a typical boarding operation. This difference is primarily caused by operators' difficulty in creating mental representations (i.e., cognitive maps) of work sites. Operators have two opportunities to acquire information, namely before work and during work, because the introduction of teleoperation requires about one week. Therefore, we have developed a view system to be used before work to provide environmental information concerning work sites on the basis of human spatial cognition. Cognitive maps can be built by acquiring knowledge from two perspectives-the survey perspective and the route perspective. We display an external view from any viewpoint to acquire knowledge from a survey perspective and a view from an operator's viewpoint, which can be modified by the operator's intention to acquire knowledge from the route perspective. Experimental results using a simulator suggested that a proposed view system could help operators acquire cognitive maps, which may lead to a decrease in task time, the number of stops, and the moving distance and an increase in speed during grasping.

Cooperative work with wearable robotics designed as an “extended body” for the wearer has the potential to improve individual productivity regardless of the context. The final purpose of this research it to design a new communication method between the wearer and a wearable robot arm as they perform daily chores simultaneously. Among previous studies on wearable robot arms, very little quantify the magnitude of the impact of robot operation on attention distribution and psychological burden for the user. The present paper presents an approach based on the idea that the robot arm could understand human intentions by reading implicit instruction cues nested in the natural motion flow of the operator performing a task. The present paper describes an Inertial Measurement Unit (IMU) sensor data - deep learning approach that enables the robot arm to learn these cues. The validity of the method was evaluated on three indexes: implicit instruction estimation accuracy, secondary task completion quality, and cognitive burden for the wearer. Results showed considerable improvement on all these proposed axes compared to other explicit operation methods (such as voice instructions), along with better results than similar implicit instruction-based researches.

Detachable Body is a new concept of a robot arm wearable as an extended part of the body. It can be detached from the user's natural body; it can be attached not only to another person but also anywhere in the environment. Humans can eventually perform tasks that involve co-presence, or tasks that are concurrent and performed in two separate places, by utilizing the Detachable Body. In this letter, we design an information presentation interface to concurrently manage both the natural and detached bodies that are located in two separate locations. The interface consists of a vision presentation system that superimposes two environment images with binocular disparity, and a proprioception presentation system that provides somatosensory feedback of the detached arm's position. The usability of the proposed interface was evaluated by measuring work efficiency and subjective evaluation in a task involving co-presence. The results suggest the existence of the effects of the binocular disparity in the vision presentation system and the tactile information provided via feedback.

An increasing research dedication has been devoted recently to soft robotics. Soft robots are best known for their compliance and safety that nominate them substantially for human-centered applications. Robot-assisted surgical operations are expanding worldwide where soft robots find their potential way for this application. Soft robots are fabricated from highly nonlinear soft materials like silicone rubbers that exhibit complex combined hyperelastic, viscoelastic, and hysteresis behaviors. Dynamic modeling of soft robots that incorporate different soft materials with fiber-reinforcement involves many considerations and depends on the underlying design concept. Establishing a certain dynamic model can be valid for a certain design configuration that may not be applicable to another one. This work proposes a transient finite element analysis-based methodology for design and dynamic simulation of fiber-reinforced soft robots for minimally invasive surgery. This methodology is based on cohesive material testing and modeling paradigms and aims to found a generalized theoretical framework for the development and experimentation of soft robots. A multi-camera vision tracking system is proposed for monitoring the 3D soft robot moving trajectory. Experimental validation of the proposed methodology proves its reliability and accuracy for estimating the soft robot dynamic response upon different actuation scenarios. The suggested methodology can be utilized in the future for developing new soft robots, devising, and testing new dynamic models or control algorithms for soft robots.

BACKGROUND: Unilateral spatial neglect (USN) is defined as impaired attention to sensory stimuli on one side. The symptoms can exist for near and far spaces combined or independently. Thus, it is important to evaluate both possibilities in a clinical environment. OBJECTIVE: To develop a tractable immersive virtual reality (iVR) system that can evaluate both near and far space neglect along with a proof of concept study to determine whether near and far spatial neglect could be described in an actual patient with USN. METHODS: An object-detecting task was developed in a three-dimensional virtual reality space. The examiner recorded the positional data of objects that were recognized by the patient with USN using coordinate data. RESULTS: The system could be used to detect near and far space neglects in a patient with USN. No side effects such as vertigo were seen during measurement. This patient showed that the angle for recognition was significantly larger for near space than far space, and exhibited a tendency for the angle of recognition to increase with lower height. CONCLUSIONS: Our proof of concept study indicated the possibility of applying an evaluation system that separates far and near space neglect using iVR.

Since the fetal heart is small and less visible, physicians find it based on the fetal position and orientation assumed with acquired US images. Meanwhile, an artifact due to bones and fetal movement in uterus not only makes the procedure cumbersome but also limits the reliability of diagnosis. Then, this paper proposes the robotic US imaging system allows for the estimation of fetal position and orientation based on the fetal bone distribution which is a key anatomical feature to detect the heart and to avoid the artifact. We obtain intrauterine bone distribution in three dimensions from echo images and estimate the fetal position and abdominal sagittal axis by calculating and analyzing the bone distribution in the entire uterus. The estimation errors in the 3D space were as follows: head position 30.9 +/- 13.9 mm, pelvis position 16.0 +/- 2.7 mm, and rotation angle 6.0 +/- 7.8 degrees. These results suggest that the proposed method is effective as a technique for estimating the approximate fetal position and has a potential to determine the heart position.

Wearable robot arm systems have been proposed that enable various tasks that humans can not do with their only two natural arms. However, many of these do not have a somatosensory feedback system so that users have to confirm the robot's state by looking every time. This active confirmation can often be a 'switching cost' of task and reduce the multitasking efficiency performed by natural arms and additional robotic arm. In this paper, we focused on the proprioception among the somatosensation, and propose a 'Position haptic belt' which is a new biofeedback system for a wearable robot arm. The system represents the three-dimensional position of a robot hand by the vibrator's placement and vibration frequency. The prototype we developed is able to identify the robot hand position with an accuracy of about 10 cm, and it is used to conduct a case study to evaluate the usability in multiple task situation. The result suggested that the effectiveness of the somatosensory feedback information of robot hand position, even for the wearable robot arm which can be easily confirmed its state on user's own eyes.

Development of sinter-free stretchable conductive inks is critically important to expand the range of materials and applications for flexible electronics. However, conventional stretchable conductive inks require high temperature sintering, which may damage the heat-frail substrates. In this study, we developed sinter-free stretchable conductive inks composed of polystyrene-block-polybutadiene-block-polystyrene (SBS) and silver flakes in tetrahydrofuran (THF). The high volatility and polarity of THF induced the densification and alignment of silver flakes in the SBS matrix, where silver flakes with large surface area and high aspect ratio were formed into the multistacked structure, resulting in the increase of conductive pathways in the stretched wiring.

Inserting a fine needle presents a trade-off problem between safety and accuracy. As one of the serious complications due to tissue damages during needle insertion, severe bleeding often occurs owing to blood vessel puncture. However, there are few researches to evaluate the safety quantitatively regarding bleeding during the fine needle insertion. Therefore, the purpose of this study was the quantitative evaluation of the amount of bleeding due the artery and vein puncture depending on the needle size. We developed a blood circulation system for measuring the amount of bleeding due to blood vessel puncture. Using the system, the amount of bleeding due to different needle sizes was evaluated. The results suggested that the amount of bleeding per unit time increased depending on the needle radius. According to ordinal safety standards, the 22-gauge needle is appropriate for insertion into the lower abdomen.

In this research, we consider a small-degree-of-freedom (SDOF) end effector aimed at absorbing position error and object shape difference. The end effector that can grasp various shapes with a SDOF simplifies the control method and thus improves versatility for existing robot systems. However, the conventional SDOF end effector cannot perform precise operation as compared with high degrees of freedom, so it becomes weak against shape difference and position error of the object to be held. Therefore, in this research, we focused on 'drawing function' and 'adapting function' which are effective for error absorption and developed an end effector capable of absorbing errors by integrating them into a SDOF. We evaluated the error absorption performance of the developed integrated end effector and examined the mechanism.

This paper presents an experimental evaluation of a usability of a wearable robot arm in different combinations of arm mechanics and attachment positions. A wearable robot arm has been recently proposed as a new system concept for the assistance of activities of daily living. Wearable robot arms are expected to enhance our physical abilities and perform multiple tasks simultaneously. However, the usability study of a wearable robot arm has not been discussed sufficiently in the concept design phase. In particular, an experimental comparison of arm mechanics and attachment positions has not been verified in the previous work. We therefore conducted a usability evaluation with a hypothetical attached robot arm which performs a representative task of activities of daily living. The time required for the experimental task and score of NASA Task Load index was evaluated. Two design concepts of a wearable robot arm is suggested according to the usability analyses: shoulder attached articulated robot arm and chest attached spherical robot arm.

The present study introduces a haptic-based biofeedback device that supplements the foot pressure information of a paretic foot using a wearable vibrotactile biofeedback device attached to the back. This system provides information pertaining to the hemiplegic patient's foot pressure pattern, both to the patient and the physical therapist. To verify the effect of the device, a 3-week pilot clinical trial was conducted on six patients (mean age: 56.8 ±11.4 years). Intervention was performed three times a week. After the intervention training, we observed significant improvement in stride length of the unparalyzed leg (p=0.0277). Moreover, the plantar flexion angle of the paralyzed side showed marginal improvement (p=0.0747). These results suggest that this device has the potential to improve the efficiency of push off function. However, the device did not improve ankle dorsiflexion of the paralyzed side, cadence and the walking speed. We speculate that the device, to some extent, imposed a cognitive burden, which may have interfered with the change in specific joint movements and limited its impact on comprehensive walking ability.

We present a wearable haptic assistance robotic system for augmented motor learning called Naviarm. This system comprises two robotic arms that are mounted on a user's body and are used to transfer one person's motion to another offline. Naviarm pre-records the arm motion trajectories of an expert via the mounted robotic arms and then plays back these recorded trajectories to share the expert's body motion with a beginner. The Naviarm system is an ungrounded system and provides mobility for the user to conduct a variety of motions. In this paper, we focus on the temporal aspect of motor skill and use a mime performance as a case study learning task. We verified the system effectiveness for motor learning using the conducted experiments. The results suggest that the proposed system has benefits for learning sequential skills.

Haptic-based vibrotactile biofeedback (BF) is a promising technique to improve rehabilitation of balance in stroke patients. However, the extent to which BF training changes temporal structure of the center of pressure (CoP) trajectories remains unknown. This study aimed to investigate the effect of vibrotactile BF training on the temporal structure of CoP during quiet stance in chronic stroke patients using detrended fluctuation analysis (DFA). Nine chronic stroke patients (age; 81.56 ± 44 months post-stroke) received a balance training regimen using a vibrotactile BF system twice a week over 4 weeks. A Wii Balance board was used to record five 30 s trials of quiet stance pre- and post-training at 50 Hz. DFA revealed presence of two linear scaling regions in CoP indicating presence of fast- and slow-scale fluctuations. Averaged across all trials, fast-scale fluctuations showed persistent dynamics (α = 1.05 ± 0.08 for ML and α = 0.99 ± 0.17 for AP) and slow-scale fluctuations were anti-persistent (α = 0.35 ± 0.05 for ML and α = 0.32 ± 0.05 for AP). The slow-scale dynamics of ML CoP in stroke patients decreased from pre-training to post-BF training (α = 0.40 ± 0.13 vs. 0.31 ± 0.09). These results suggest that the vibrotactile BF training affects postural control strategy used by chronic stroke patients in the ML direction. Results of the DFA are further discussed in the context of balance training using vibrotactile BF and interpreted from the perspective of intermittent control of upright stance.

We use ultrathin polymer film called nanosheet to develop wearable battery-less devices which don’t need adhesive to be attached to the skin. Considering NFC (Near Field Communication) is not suitable for the skin-adhesive devices because the capacitance between the skin and the antenna coil reduces the voltage, we adopt electric NFC to transmit data and power to communicate through the human body. We measured the relationship between the IC tag yield rate and the three factors: the area of the electrodes, the distance between the two electrodes, and the thickness of the nanosheet. All of the 6 devices worked and the electric NFC devices are 79% thinner than the conventional NFC devices. Thus, electric NFC enables nanosheet devices to work without batteries.

We present a wearable haptic assistance robotic system for motor learning. This system comprises two robotic arms that are mounted on a user’s body and are used to transfer one person’s motion to another offline. The system pre-records the arm motion trajectories of an expert via the mounted robotic arms and then plays back these recorded trajectories to share the expert’s body motion with a beginner. The system is an ungrounded system and provides mobility for the user to conduct a variety of motions. In this paper, we focus on the temporal aspect of motor skill and use a mime performance as a case study learning task. We verified the system effectiveness for motor learning using the conducted experiments. The results suggest that the proposed system has benefits for learning sequential skills.

It is known that walking dysfunction occurs the stroke patients with hemiplegia and it declines quality of life. Even though cadence of stroke patients is one of the most significant factor of walking ability, it is difficult to improve the cadence of gait without abnormal effortful movement. Thus, we developed the implicit cueing device to improve the cadence in stroke patients. In this paper, we used the weber-ratio to prevent the notice of the change of cadence, and calculated the ratio through experimental study with stroke patients. Further, we conducted the clinical trial in six stroke patients. As a result, our study suggested that proposed device could increase the cadence of stroke patients without notice of the changes.

汗中に含まれる電解質などの化学物質を連続的に計測することで症状の早期発見を目的とした健康モニタリングデバイスへの関心が高まっている.我々はこれまで皮膚貼付型汗中イオン計測デバイスの開発を目的とし,ISFETを用いた小型軽量な低消費電力回路設計技術を構築してきた.しかし,汗に直接センサを押し当てて測定する場合,不純物の混入や気化によって濃度が高くなるという問題がある.そこで本研究では,マイクロ流路を用いて汗の吸上げから排出までを受動的に行い,その過程でイオンを計測可能な皮膚貼付型電子デバイスの開発を目的とする．上記目的を実現すべく,流路には親水性の高い材料を使用した.また,マイクロ流体は層流であり,電解質などの物質は拡散の影響を受けやすい.よって,吸上げ上部の流路壁面の一部をISFETに置き換え,測定結果に拡散の影響が生じないようにした.上記設計の有用性を検証すべく,人工汗液を流し,溶液の先端位置と経過時間の計測を行った結果,溶液は親水性面による界面張力を受け受動的に流動した.また,溶液の濃度を変化させたところ,濃度変化後,約12秒の遅れは生じるが変化を測定できた.よって,汗イオン濃度計測が有用である可能性が示唆された.

The final purpose of this research is to develop an echocardiography diagnostic robot. In previous research of echocardiography diagnostic robots, it could not secure sufficiently the safety of patients because of binding inspection posture by robots. This paper is aimed at presenting new postures for echocardiography diagnostic robots which are not bounded by robots and can keep the quality of the echo images. In order to find those, the examination was conducted with a doctor’s cooperation. As a result, new postures are suggested. Next in order to evaluate patient’s physical burden, the authors developed an inspection support structure by which patients can retain new postures. At last, the authors evaluated patient’s physical burden by the structure. As a result, new postures for echocardiography diagnostic robots in consideration of the quality of the echo images and patient’s physical bound are suggested.

In this research, to reduce Feedback cognitive load, we proposed a method to limit the state information of extended body to only hand position information which is physical point of action with environment, and development and recognition accuracy of Feedback device. As a proposed method, we created a Haptic Feedback Belt that expresses the position of the tip of the robot arm by vibration presentation to the lumbar region. As a verification test, the hand position recognition accuracy of the robot arm was verified with the vibration FB applied. The distance error from the target point was 10.1 [cm] on average for single task and 17.9 [cm] on average when vibration FB was not given, which was a significant difference. The result suggests that the hand position of the robot arm can be grasped by using this device.

In recent years, attention has been gaining attention for interchanges between children and the elderly, but in the present situation it is a problem to stay at single-shot event exchanges. Therefore, we developed a system that collaborates with elderly people and children through nurturing avatars in order to carry out continuous daily exchanges, not only for event exchanges but also for verifying the effect. As a result of using this system, the amount of mutual conversation time increased compared to the exchange that has been done conventionally. Therefore, it was suggested that this system has the effect of promoting exchange.

The purpose of this study was to develop an additional and remotely controllable robotic limb called “Detachable Body” which enable perform two concurrent tasks. In this paper, we studied the video presentation method to enable perform two concurrent tasks in a remote work area using “Detachable Body”. We made it possible by overlapping two images. Therefore, we comparison of preferable transmittance when images were layered. The transmittance was verified in three ways from the viewpoint of attention distribution for work. As a result, it was suggested that the transmission ratio suitable for distribution / movement of attention is 3: 7 or less in one use case.

The objective of our research is to develop the pose estimation algorithm for Karate motions using RGB Camera. Kata is the representation of Karate’s self-defense techniques strung together into a performance routine. Kata is judged based on several technical and physical criteria; including speed and strength. For this reason, quality evaluation for Karate motions by technology is difficult. In this research, we created a data set targeting karate movement. We also developed the pose estimation algorithm for Karate motions by deep learning using this data set.

Human movement based on sensory control is significant to motor task performance. Thus, impairments to sensory input significantly limit feedback-type motor control. The present study introduces a vibrotactile biofeedback (BF) system which augments information regarding the user's foot pressure to enhance gait performance. The effects of the proposed system on the gait patterns of healthy older adults and on the cognitive load during gait were evaluated; these factors are essential to clarify feasibility of the device in real-life settings. The primary task of our study was to evaluate gait along with a cognitively demanding activity in 10 healthy older adults. Regarding kinematic and kinetic data in the BF condition, the subjects had significantly increased ankle dorsiflexion during the heel contact phase in the sagittal plane and marginally increased foot pressure at the toe-offand stride length. However, such kinematic and kinetic changes were not attributed to the increased walking speed. In addition, cognitive performance (i.e., the number of correct answers) was significantly decreased in participants during gait measurements in the BF condition. These data suggest that the system had the potential for modifying the kinematic and kinetic patterns during walking but not the more comprehensive walking performance in older adults. Moreover, the device appears to place a cognitive load on older adults. This short report provides crucial primary data that would help in designing successful sensory augmentation devices and further research on a BF system.

We measured the conformability and adhesion energy of a polymeric ultrathin film "nanosheet" with hundreds of nanometer thickness to a skin model with epidermal depressions. To compare the confirmability of the nanosheets with different thicknesses and/or under different attaching conditions, we proposed a measurement method using skin models with the same surface profile and defined the surface strain ϵS as the quantified value of the conformability. Then, we measured the adhesion energy of the nanosheet at each conformability through a vertical tensile test. Experimental results indicate that the adhesion energy does not depend on the liquid used in wetting the nanosheet before attaching to the skin model and increases monotonously as the surface strain ϵS increases.

Background: Most individuals have sensory disturbances post stroke, and these deficits contribute to post-stroke balance impairment. The haptic-based biofeedback (BF) system appears to be one of the promising tools for balance rehabilitation in patients with stroke, and the BF system can increase the objectivity of feedback and encouragement than that provided by a therapist. Research question: Studies in skill science indicated that feedback or encouragement from a coach or trainer enhances motor learning effect. Nevertheless, the optimal BF system (or its concept) which would refine the interpersonal feedback between patients and therapist has not been proposed. Thus, the purpose of this study was to propose a haptic-based perception-empathy BF system which provides information regarding the patient's center-of-foot pressure (CoP) pattern to the patient and the physical therapist to enhance the motor learning effect and validate the feasibility of this balance-training regimen in patients with chronic stroke. Methods: This study used a pre-post design without control group. Nine chronic stroke patients (mean age: 64.4 ± 9.2 years) received a balance-training regimen using this BF system twice a week for 4 weeks. Testing comprised quantitative measures (i.e., CoP) and clinical balance scale (Berg Balance Scale, BBS
Functional Reach Test, FRT
and Timed-Up and Go test, TUG). Results and significance: Post training, patients demonstrated marginally reduced postural spatial variability (i.e., 95% confidence elliptical area), and clinical balance performance significantly improved at post-training. Although the changes in FRT and TUG exceeded the minimal detectable change (MDC), changes in BBS did not reach clinical significance (i.e., smaller than MDC). These results may provide initial knowledge (i.e., beneficial effects, utility and its limitation) of the proposed BF system in designing effective motor learning strategies for stroke rehabilitation. More studies are required addressing limitations due to research design and training method for future clinical use.

Recently, burdens of both doctors and pregnant women has been increased due to the decrease of obstetricians. In order to solve those problems, we aimed to develop the prenatal care robot for supporting ultrasound diagnosis. Although we developed the ultrasound prove control unit in the previous study, there are some problems about the support way of the unit in terms of the safety and operability. In this paper, we reported that the dead-weight compensation arm for positioning the prove control unit passively. By combing both counter weight and spring, we realize the dead-weight compensation with operability in clinical situation.

Rehabilitation from the acute phase to recover voluntary after stroke onset has attracted attention in recent years. We have developed a rehabilitation device that moves the paralyzed foot in the supine position and triggered by the non-paralyzed foot. In this study, we devised a rehabilitation method to expand the voluntary by changing the assist according to the voluntary of the paralyzed foot, and developed a control system that realizes the method using the existing device. In the evaluation test, a strong correlation was found between IEMG of the paralyzed foot and the assist amount, which .suggested that the proposed method was realized.

For percutaneous needle insertion in the lower abdomen, preoperative insertion path planning with CT imaging is important. Previous studies have shown that needle deflection can be minimized by selecting an insertion path for which the sum of the insertion angles on the tissue boundaries is minimized. To apply the concept of path planning to the clinical setting, a system must be developed to automatically calculate the insertion angle and determine the optimal insertion path on CT images. We herein present a method for multilayered tissue boundary detection in the lower abdomen and insertion angle calculation along the insertion path based on the boundary detection. Because this detection method does not depend on the tissue shape, the boundary points showing a peak brightness change on each insertion path are detected and connected. The experimental results showed an average insertion angle error in the skin, muscle, and bowel of 0.68, 0.99, and 5.3 degrees, respectively.

Fine needle deflection is a problem encountered during insertion into a soft tissue. Although an axial rotational insertion is an effective approach for minimizing this problem, needle deflection still depends on the insertion angle with respect to the tissue boundary. Since the human body consists of multi-layered tissues of various shapes and mechanical properties, preoperative planning of an optimal path is a key factor for achieving a successful insertion. In this paper, we propose an optimization-based preoperative path planning model that minimizes needle deflection during multi-layered tissue insertion. This model can determine the optimal path based on the sum of insertion angles with respect to each tissue boundary that the needle passes through. To increase the accuracy of the model, we incorporated the effect of distances from tissue boundaries and the probability that the deflection is acceptable by incorporating weighting factors into the model. To validate the model, we performed experiments involving four scenarios of two- and three-layered tissues. The results showed that the proposed model is capable of determining the optimal insertion path in all scenarios.

In clinical practice, therapists often encounter cases of unilateral spatial neglect (USN) observed in far and near space. In this case report, immersive virtual reality (VR) technology was adopted as a therapy tool in a patient with stroke with severe near and far space neglect. Neuropsychological tests in near and far space as well as the Catherine Bergego Scale (CBS), as an index of neglect in daily living, were measured preintervention and postintervention. Improvement of neuropsychological tests, particularly in far space, was clearly demonstrated postintervention. However, CBS score did not change postintervention. This may be because the patient unsuccessfully translated these visual search task skills used in far space to activities of daily living. Our findings suggest the potential use of immersive VR technology in patients with USN and highlight the VR programme's limited ability to fully recover a patient's disability in natural settings.

Fine needle deflection is a problem encountered during insertion into a soft tissue. Although an axial rotational insertion is an effective approach for minimizing this problem, needle deflection still depends on the insertion angle with respect to the tissue boundary. Since the human body consists of multi-layered tissues of various shapes and mechanical properties, preoperative planning of an optimal path is a key factor for achieving a successful insertion. In this paper, we propose an optimization-based preoperative path planning model that minimizes needle deflection during multi-layered tissue insertion. This model can determine the optimal path based on the sum of insertion angles with respect to each tissue boundary that the needle passes through. To increase the accuracy of the model, we incorporated the effect of distances from tissue boundaries and the probability that the deflection is acceptable by incorporating weighting factors into the model. To validate the model, we performed experiments involving four scenarios of two- and three-layered tissues. The results showed that the proposed model is capable of determining the optimal insertion path in all scenarios.

In teleoperation of heavy machines, work efficiency will be 50% lower than manned operation because operators cannot obtain effective information about work sites due to the limitation of current monitoring systems. Operators would have opportunities to obtain such information before work (about a week required to introduce teleoperation systems) and during work. As a fundamental study to support operator's spatial cognition, we developed views to provide spatial information of work sites before work. Humans have cognitive maps which are created based on knowledge acquired from survey and route perspectives. To make operators acquire the above two knowledge, we provide a bird's-eye view that can be changed by operators to acquire a knowledge from survey perspective, and a view from operator's viewpoint that can be changed by operator's intention to acquire a knowledge from route perspective. To evaluate two pre-offering views, we preformed experiments using a virtual reality simulator. The results indicated that a view to acquire a knowledge from survey perspective could help operators plan totally and one to acquire a knowledge from route perspective could help operators plan locally, and could increase work efficiency.

This paper explores the effectiveness of applying a deep learning based method to segment the amniotic fluid and fetal tissues in fetal ultrasound (US) images. The deeply learned model firstly encodes the input image into down scaled feature maps by convolution and pooling structures, then up-scale the feature maps to confidence maps by corresponded un-pooling and convolution layers. Additional convolution layers with 1×1 sized kernels are adopted to enhance the feature representations, which could be used to further improve the discriminative learning of our model. We effectively update the weights of the network by fine-tuning on part of the layers from a pre-trained model. By conducting experiments using clinical data, the feasibility of our proposed approach is compared and discussed. The result proves that this work achieves satisfied results for segmentation of specific anatomical structures from US images.

This paper proposes a practical scheme for measuring the mass of an object grasped by the end-effector of a large-scale hydraulic manipulator. Such a measurement system requires high accuracy and robustness considering the nonlinearity and uncertainty in hydraulic pressure-based force measurement during rigorous outdoor work. It is thus difficult to precisely model system behaviors and completely remove error force components (white-box modeling) under such conditions, so our scheme adopts a less-error data selection approach to relatively improving the accuracy and reliability of the measurand (gray-box modeling). It first removes dominant error forces, i.e., gravity and dynamic friction forces, then defines the on-load state by evaluating measurement conditions to omit data in indeterminate conditions, then extracts data during the object-grasp state identified by a grasp motion model and removes high-frequency components by a simple low-pass filter, and finally integrates data from multiple sensors using the posture-based priority and averages all selected data. Evaluation experiments were conducted using an instrumented hydraulic arm. Results indicate that our scheme can precisely measures the mass of the grasped object under various detection conditions with fewer errors.

In this paper, we present a simple method for manufacturing electronic devices using ultrathin polymer films, and develop a high-frequency RF identification. To expand the market for flexible devices, it is important to enhance their adhesiveness and conformability to surfaces, to simplify their fabrication, and to reduce their cost. We developed a method to design an antenna for use on an operable RF identification whose wiring was subjected to commercially available inkjet or simple screen printing, and successfully fabricated the RF identification. By using ultrathin films made of polystyrene-block-polybutadiene-block-polystyrene (SBS) as substrates-less than 750nm-the films could be attached to various surfaces, including soft surfaces, by van der Waals force and without using glue. We succeeded in the simple fabrication of an ultrathin RF identification including a commercial or simple printing process. (C) 2017 The Japan Society of Applied Physics

In this paper, we present a simple method for manufacturing electronic devices using ultrathin polymer films, and develop a high-frequency RF identification. To expand the market for flexible devices, it is important to enhance their adhesiveness and conformability to surfaces, to simplify their fabrication, and to reduce their cost. We developed a method to design an antenna for use on an operable RF identification whose wiring was subjected to commercially available inkjet or simple screen printing, and successfully fabricated the RF identification. By using ultrathin films made of polystyrene-block-polybutadiene-block-polystyrene (SBS) as substrates-less than 750nm-the films could be attached to various surfaces, including soft surfaces, by van der Waals force and without using glue. We succeeded in the simple fabrication of an ultrathin RF identification including a commercial or simple printing process. (C) 2017 The Japan Society of Applied Physics

We fabricated free-standing, flexible and physically adhesive ultrathin elastomeric films (nanosheets) for application as electronic substrates and packaging films. In this work, electronic elements such as a chip resistor and a chip LED were sandwiched between elastomeric nanosheets of less than 1 mu m thickness to obtain electrical conduction in silver lines that were inkjet-printed on the nanosheet. This sandwich-fixation process contributed to the development of an electronic device showing conformable adhesion and operation on the skin surface.

<p>Recently, the importance of "Visual ability in sports" called "Sports Vision(SV)" is insisted. On the other hand, there are very few devices that train SV. In the previous study, the ability of Volleyball spike is related to SV(KVA[Kinetic Visual Acuity] and HEC[Hand-Eye Coordination]).In the present study, we developed two systems that train SV by immersive 3D-VR;KVA training system and HEC training system. The former trains KVA by watching 3D-VR images of coming up numger while changing. The latter trains HEC by watching 3D-VR images of Volleyball spike and moving arms and gives the visual BF. Pre-post test found that users of the KVA training system increased their KVA.</p>

<p>The purpose of this study was to develop an additional robotic limb called "Third Arm" with which it is possible to perform two concurrent tasks. In this paper, we propose a control method based on the "Face Vector," which selects a target object using face direction as an interface for Third Arm. There are two requirements (to acquire the Face Vector and to fix the system to the head without interfering with the field of view) of the interface. For the first requirement, it was possible to acquire the Face Vector using an IMU sensor and a distance-measuring laser sensor (100 Hz). For the second requirement, by using eyeglasses, we solved this problem without interfering with the field of view. We verified the accuracy of the interface and found an average target error of 1.83 cm. The results suggest that the distance-measuring laser diffused on the curved surface.</p>

<p>For accurate insertion by CT-guided robot, we need registration between the coordinate of robot and CT by calculating the section images. In this paper, we intended to develop geometric the marker for registration. The requirements are geometric shapes that the error of 3 DOF (yaw and pitch angles and a craniocaudal distance) between CT image and the maker can be calculated and the material is suitable for CT imaging. Then, marker has four oblique prisms to calculate the error of 3DOG. Oblique prism has advantage on the point of reducing error of angle calculation because of the slope of inverse trigonometric function. From the result of evaluation, accuracy of registration system by geometric marker is satisfactory for insertion to the tumor in lower abdominal region.</p>

Accurate insertion of fine needles is difficult due to needle deflection. Needle deflection in the lower abdomen is particularly complex, as the needle has to pass through various tissues. As the area of the bowel is dominant in lower abdominal insertion, it is important to analyze the deflection during bowel insertion and to control the needle to minimize deflection. Few studies have focused on bowel insertion. We performed a fundamental deflection analysis of needle insertion in the bowel. Moreover, we have proposed an insertion method for minimizing the needle deflection based on our analysis. First, we performed needle insertion at various insertion positions and insertion angles into the hollow-shaped bowel, and determined the trend of the needle deflection during bowel insertion. The results revealed that the needle deflection was increased due to an increase in insertion angle, and therefore insertion angle should be minimized as much as possible. However, during actual bowel needle insertion, there are many situations in which the ideal path cannot be selected due to the arrangement of the bowel loops. We proposed an insertion method that can eliminate the total needle deflections during bowel insertion by controlling the needle tip direction at the breaching of each bowel wall. The results suggest that the needle deflection can be minimized by selecting the insertion path in which the sum of each insertion angle is zero. We verified the results of this insertion method in multiple bowels in in vivo experiments, and showed that it has the potential to be used in clinical practice.

Fine needles can easily be deflected, making accurate needle insertion into a tumor difficult. In particular, it is difficult to insert the needle into a tumor in the lower abdomen because the needle has to pass through various tissues. Therefore, for lower abdominal needle insertion, we intend to develop a planning method for the optimal insertion path to minimize the deflection based on computed tomography images. In this letter, we analyze the deflection while performing needle insertion with axial rotation under conditions of various insertion angles into individual tissues composing the lower abdomen (pork loin and porcine small bowel) and develop a basic planning procedure to determine the optimal insertion path based on the analysis. From the results, we confirmed that the insertion angle should be minimized as much as possible. We then develop a planning method based on insertion angles into individual tissues the needle needs to pass through. We assumed that it is possible to determine the optimal insertion path by providing a weighting factor to the effect of the insertion angle depending on the depth of insertion, considering that the effect of the insertion angle on deflection in deep places of the body is smaller than the effect around the body surface. To verify the concept of the proposed planning procedure, we perform experiments with a simple model composed of two tissues. From the results, we show that the optimal insertion path can be planned by setting the optimal ratio of individual weighting factors.

Background: Impaired balance in patients with hemiparesis caused by stroke is frequently related to deficits in the central integration of afferent inputs, and traditional rehabilitation reinforces excessive visual reliance by focusing on visual compensation.Objective: The present study investigated whether a balance task involving a haptic biofeedback (BF) system, which provided supplementary vibrotactile sensory cues associated with center-of-foot-pressure displacement, improved postural control in patients with stroke.Methods: Seventeen stroke patients were assigned to two groups: the Vibrotactile BF and Control groups. During the balance task (i.e., standing on a foam mat), participants in the Vibrotactile BF group tried to stabilize their postural sway while wearing the BF system around the pelvic girdle. In the Control group, participants performed an identical postural task without the BF system.Results: Pre- and post-test measurements of postural control using a force plate revealed that the stability of bipedal posture in the Vibrotactile BF group was markedly improved compared with that in the Control group.Conclusions: A balance task involving a vibrotactile BF system improved postural stability in patients with stroke immediately. This confirms the potential of a haptic-based BF system for balance training, both in routine clinical practice and in everyday life.

<p>Acquiring one's own form is an important technique for excelling in any competitive sport. Most basketball players spend a significant amount of time in acquiring the ideal form in order to improve their basketball skills. Although basketball is one of the most popular sports in the world, there are only few devices that aid in improving a player's skills. In the research involving the development of a skill-support device for basketball, it is important to learn the ideal form to acquire a physical posture of set-form. Therefore, we developed a device for reforming the set-form using auditory biofeedback. The proposed device measures the shoulder angle of a player in real time (50 Hz) and generates a sound on the basis of the measured angle to inform the ideal posture. If the set-form posture is not ideal, the device uses this sound to inform the player that they must modify their posture. The player then changes their shoulder angle and if the posture becomes ideal, the device mutes the sound. Several seconds after the sound stops, the device indicates the player to shoot. According to our study for testing the efficacy of this device, the BF-training group obtained 20% higher success rate than the control group. Moreover, the BF-training group had a more stable form than the control one.</p>

Cancer vaccine therapy is a novel treatment method which uses an extra-fine (0.53 mm in diameter (25 G)) needle to deliver a tumor-specific vaccine directly into a tumor. This method is expected to deliver an effective treatment with few side effects. However, the procedure is very difficult to perform because of needle deflection. We intend to develop a needle insertion robot to combat this deflection and deliver the vaccine successfully. The key features of the robot were developed to minimize needle tip deflection while traversing complex tissues which is composed of various tissues. In this paper, as targeted to lower abdomen, we propose a control method for minimizing needle tip deflection during insertion through vibration and axial rotation. The effectiveness of the proposed method was evaluated in artificial and biomaterial tissues found in the lower abdomen (muscle, bowel, and skin). Results demonstrated that the effectiveness of vibration and rotation was changed depending on the kind of the tissues. The rotation was effective to the thick tissues (muscle and skin) and the vibration was effective to membranous tissues (bowel). Based on the results, our method used vibration and rotation when the needle is inserted into the skin and muscle and only vibration when traversing through soft tissue such as the bowel. In conclusion, the proposed method can minimize needle tip deflection robustly in a lower abdomen phantom.

Background: Unilateral spatial neglect (USN) is defined as impaired ability to attend and see on one side, and when present, it interferes seriously with daily life. These symptoms can exist for near and far spaces combined or independently, and it is important to provide effective intervention for near and far space neglect.
Objective: The purpose of this pilot study was to propose an immersive virtual reality (VR) rehabilitation program using a head-mounted display that is able to train both near and far space neglect, and to validate the immediate effect of the VR program in both near and far space neglect.
Methods: Ten USN patients underwent the VR program with a pre-post design and no control. In the virtual environment, we developed visual searching and reaching tasks using an immersive VR system. Behavioral inattention test (BIT) scores obtained pre- and immediate post-VR program were compared.
Results: BIT scores obtained pre-and post-VR program revealed that far space neglect but not near space neglect improved promptly after the VR program. This effect for far space neglect was observed in the cancelation task, but not in the line bisection task.
Conclusions: Positive effects of the immersive VR program for far space neglect are suggested by the results of the present pilot study. However, further studies with rigorous designs are needed to validate its clinical effectiveness.

We investigated whether a biofeedback system that provided supplementary vibrotactile sensory cues associated with the center of foot pressure displacement contributes to postural control in a patient with transtibial amputation. Postural stability using a force plate revealed improved stability of the bipedal posture only in the eyes-closed condition, but not in the eyes-open condition, and this effect had a brief carry-over effect. We found that this patient achieved postural control mainly using visual information, and since the vibrotactile biofeedback improved postural stability in the eyes-closed condition, there seems to exist sensory substitution for postural control. This confirms the potential of a haptic-based BF system for balance training, both in routine clinical practice and in everyday life.

Needles used in percutaneous insertion must be as thin as possible to minimize invasiveness. However, using extra-thin needles with a diameter less than 25G (0.53 mm diameter) can cause needle deflection. Needle deflection can be minimized by insertion with axial rotation along the needle shaft; this rotation is also useful for steering the insertion direction of the needle tip. However, although high rotation speeds may decrease needle deflection, this may increase tissue damage. Therefore, the purpose of this study was to histologically evaluate tissue damage caused by the rotational needle-insertion method, and to verify the needle-tip deflection caused by tissue damage. In this paper, we evaluated tissue damage and needle deflection caused by needle insertion with no rotation, unidirectional rotation, and bidirectional rotation. The results suggest that percutaneous needle insertion under unidirectional rotation is potentially risky in humans, as this causes wound-up tissue and expansion of the area of the hole created by the needle path. In contrast, needle insertion under bidirectional rotation appeared to minimize deflection, and prevented winding of tissue and expansion of the hole created by the needle path.

Recent studies have shown that haptic feedback on the body, either at or away from the desired gait parameter to be changed, can improve gait performance. Here we introduced a haptic-based biofeedback device to supplement the foot pressure information of a paretic foot with a wearable vibrotactile biofeedback device attached to the back. This system provides information regarding a patient's foot pressure pattern to the patient and physical therapist. Therefore, the biofeedback system can share information regarding abnormal gait patterns between patients and therapists. This pilot study showed that the device immediately improved the stride length during walking, but not walking speed. Furthermore, subjective reports indicated that synchronizing foot pressure pattern information between the patient and therapist induced higher patient motivation for gait rehabilitation.

In unmanned construction, work efficiency is lower than that in manned construction due to lack of visual information. Thus, we previously developed an autonomous camera control system to provide various visual information suited to work states through multiple displays. However, that system increased the cognitive load on operators, and required them to have much experience to choose appropriate views for various situations. Next, we should investigate the degree of effectiveness for each view in a certain state. Thus, in this study, we analyzed gaze patterns to clarify which are the displays that operators often watch in work states, i.e., moving, grasping, transport, and releasing. We then derived which gaze patterns have higher work performance, including time efficiency and safeness. We clustered gaze patterns using Ward's method, which is a criterion applied in hierarchical clustering. To evaluate the objective of this study, we conducted experiments involving debris transport tasks, using a virtual reality simulator. The results indicated that gaze patterns differed in operators and we found that better time efficiency related to specific gaze patterns for each work state.

The recovery of motor function after stroke is widely considered to result from brain plasticity. However, what kind of training exercise can better provoke brain plastic processes is still unclear. Studying regional brain activation during a specific training exercise may provide value information that can help design more effective therapeutic approaches. In this paper, we monitored brain activation when subjects performed four different finger training exercises: left middle finger passive movement (LMFP), left middle finger active movement (LMFA), middle finger self-motion control movement (MF), and both middle fingers active movement (BMFA). Eight healthy volunteers were involved in this study. The results indicated that the LFMA results in stronger brain activation than the LMFP in the left insular, left inferior frontal cortex, right middle cingulate cortex, left S1, bilateral cerebellum, SMA, and right inferior frontal areas. However, we did not find a significant difference when comparing the the MF and the BMFA conditions.

This paper presents the design, development and magnetic resonance imagining (MRI) compatibility evaluation of a small size, compact and adjustable different finger phalange lengths rehabilitation device. This device employs ultrasonic motor as its actuator and adopts a novel six-link mechanism to drive the finger. The final system enables to provide two joints (the MCP and the PIP) in each finger to do flexion and extension motion with one degree of freedom (DOF). The MRI compatibility of the robot was also evaluated. The results demonstrate that there is neither an effect from the MRI environment on the robot performance, nor significant degradation on MRI images by the introduction of the robot in the MRI scanner. Finally, an fMRI study with subject was carried out, the result shows a stable brain activation was observed when the middle finger of the subject was driven to implement passive rehabilitation motion inside the MRI scanner.

A practical operator support system for disaster response work using construction machinery is applied to object-break operations using a dual-arm machine. An object-break operation, which separates an object into two different parts by applying massive pulling force, requires skillful force and trajectory controls. Operators typically have trouble visually perceiving the movement of the manipulator because the target object is strongly restrained. As a result, after the object has been separated into two pieces, the operator may continue performing lever operations because of unavoidable perception reaction time and the manipulator may collide with the surrounding environment. A control input cancellation system based on object-break identification is proposed to reduce the time difference between the object break and operation stoppage. A support system for disaster response situations must be safe and efficient and accommodate operators with various skill levels; thus, common physical phenomena related to the object breakage should be exploited. The system cancels control inputs to stop the movement of the manipulator when an object-break flag is detected, which is defined as a situation where the force applied to each joint of a manipulator decreases rapidly when a lever operation and load on the inside of the grapple are detected. Demolition experiments were conducted using a hydraulic dual-arm system. The results indicate that the displacement of the end-point after the object breaks is greatly decreased and the completion time of the task is reduced as well.

This paper proposes a quantification method for a comprehensive work flow in construction work for describing work states in more detail on the basis of analyzing state transitions of primitive static states (PSS), which consist of 16 symbolic work states defined by using on-off state of the lever operations and joint loads for the manipulator and end-effector. On the basis of the state transition rules derived from a transition-condition analysis, practical state transitions (PST), which are common and frequent transitions in arbitrary construction work, are defined. PST can be classified into essential state transition (EST) or nonessential state transitions (NST). EST extracts common phases of work progress and estimates positional relations between a manipulator and an object. NST reveals wasted movements that degrade the efficiency and quality of work. To evaluate comprehensive work flows modeled by combining EST and NST, work-analysis experiments using our instrumented setup were conducted. Results indicate that all the PSS definitely changes on the basis of PST under various work conditions, and work analysis using EST and NST easily reveals work characteristics and untrained tasks related to wasted movements.

Unmanned construction machines are used after disasters. Compared with manned construction, time efficiency is lower because of incomplete visual information, communication delay, and lack of tactile experience. Visual information is the most fundamental items for planning and judgment, however, in current vision systems, even the posture and zoom of cameras are not adjusted. To improve operator's visibility, these parameters must be adjusted in accordance with the work situation. The purpose of this study is thus to analyze effective camera images from some comparison experiments, as a fundamental study of advanced visual support. We first developed a virtual reality simulator to enable experimental conditions to be modified easier. To effectively derive required images, experiments with two different camera positions and systems (fixed cameras and manually controllable cameras) were then conducted. The results indicate that enlarged views to show the manipulator is needed in object grasping and tracking images to show the movement direction of the manipulator is needed in largely end-point movement. The result also confirms that the operational accuracy increases and blind spot rate decreases by using the manual system, com-pared with fixed system.

A method to tune a basic input/output gain (BIOG) according to usage conditions for human-machine systems is proposed for improving work performance. Adapting a BIOG is effective in terms of improving operability and work efficiency, but frequent changes using a gain scheduling strategy degrade the operability by confusing the machine dynamics. The proposed tuning system adjusts a BIOG at long intervals on the basis of comprehensive features in operator and work content obtained from the histogram of control lever input. The target value is set to the normal distribution, meaning that all ranges of the control lever are evenly used in a spring-type lever, as leveling the histogram independent of an operator and work content provides the consistent operational feeling, which leads to comfortable operability. To ensure practicality and effectiveness, a BIOG curve is set to a polygonal line involving a break point and a saturation point that are tuned by equivalent transform of area differences between the obtained histogram and normal distribution curves. Two types of experimental task were performed using a hydraulic arm system. Results showed that the proposed BIOG tuning system improves time efficiency by reducing the area difference while increasing the subjective usability compared with a conventional fixed BIOG system.

Recognizing grasped objects with tactile sensors is beneficial in many situations, as other sensor information like vision is not always reliable. In this paper, we aim for multimodal object recognition by power grasping of objects with an unknown orientation and position relation to the hand. Few robots have the necessary tactile sensors to reliably recognize objects: in this study the multifingered hand of TWENDY-ONE is used, which has distributed skin sensors covering most of the hand, 6 axis F/T sensors in each fingertip, and provides information about the joint angles. Moreover, the hand is compliant. When using tactile sensors, it is not clear what kinds of features are useful for object recognition. Recently, deep learning has shown promising results. Nevertheless, deep learning has rarely been used in robotics and to our best knowledge never for tactile sensing, probably because it is difficult to gather many samples with tactile sensors. Our results show a clear improvement when using a denoising autoencoder with dropout compared to traditional neural networks. Nevertheless, a higher number of layers did not prove to be beneficial.

A method to autonomously control multiple environmental cameras, which are currently fixed, for providing more adaptive visual information suited to the work situation for advanced unmanned construction is proposed. Situations in which the yaw, pitch, and zoom of cameras should be controlled were analyzed and imaging objects including the machine, manipulator, and end-point and imaging modes including tracking, zoom, posture, and trajectory modes were defined. To control each camera simply and effectively, four practical camera roles combined with the imaging objects and modes were defined as the overview-machine, enlarge-end-point, posture-manipulator, and trajectory-manipulator. A role assignment system was then developed to assign the four camera roles to four out of six cameras suitable for the work situation, e.g., reaching, grasping, transport, and releasing, on the basis of the assignment priority rules, in the real time. Debris removal tasks were performed by using a VR simulator to compare fixed camera, manual control, and autonomous systems. Results showed that the autonomous system was the best of the three at decreasing the number of grasping misses and error contacts and increasing the subjective usability while improving the time efficiency.

A practical framework for measuring the mass of an object grasped by the end-effector of a large-scale hydraulic manipulator, such as construction manipulators, is proposed. Such a measurement system requires high accuracy and robustness considering the nonlinearity and uncertainty in hydraulic pressure-based force measurement. It is thus difficult to precisely model the system behaviors and completely remove error force components, so our framework adopts a less-error data selection approach to improving the reliability of the measurand. It first detects the on-load state to extract reliable data for mass measurement, including evaluating measurement conditions to omit sensors in indeterminate conditions and redefining three-valued outputs such as on, off, or not determinate, to improve robustness, then extracts data during the object-grasp state identified by the grasp motion model and removes high-frequency component by a simple low-pass filter, to improve accuracy, and finally integrates date from plural sensors using the posture-based priority and averages all selected data, to improve reliability. Evaluation experiments were conducted using an instrumented hydraulic arm. Results indicate that our framework can precisely measures the mass of the grasped object in various detection conditions with less errors.

This paper introduces the design, fabrication and evaluation of the second generation prototype of a magnetic resonance compatible finger rehabilitation robot. It can not only be used as a finger rehabilitation training tool after a stroke, but also to study the brain's recovery process during the rehabilitation therapy (ReT). The mechanical design of the current generation has overcome the disadvantage in the previous version[13], which can't provide precise finger trajectories during flexion and extension motion varying with different finger joints torques. In addition, in order to study the brain activation under different training strategies, three control modes have been developed, compared to only one control mode in the last prototype. The current prototype, like the last version, uses an ultrasonic motor as its actuator to enable the patient to do extension and flexion rehabilitation exercises in two degrees of freedom (DOF) for each finger. Finally, experiments have been carried out to evaluate the performances of this device.

This paper presents our second generation prototype of a magnetic resonance compatible finger rehabilitation robot. It can not only be used as a finger rehabilitation training tool after a stroke, but also to study the brain's recovery process during the rehabilitation therapy (ReT). The finger driving mechanism in current generation is an one degrees of freedom (DOF) driving mechanism, which could overcome the disadvantage that can't provide precise finger trajectories during flexion and extension motion existing in previous version [11]. In addition, this design can also be adjustable to different persons' finger phalanges, as well as the gap between one finger to another can be easily changed. Furthermore, the kinematic analysis of the finger driving mechanism is detailed in this paper; Following, the describes of the control system and a self-motion control mode are presented. Finally, experiments have been carried out to evaluate the performances of this device.

This paper presents the design, fabricate and evaluation of a Magnetic Resonance compatible finger rehabilitation device, which could not only be used as a finger rehabilitation training tool after stroke, but also to study the brain's recovery process during the rehabilitation therapy (ReT).
The mechanics of this device are designed to be adjustable to different persons' finger phalanges, and also the gap between one finger to another can be easily changed. By using an ultrasonic motor as its actuator, the device has been designed to be portable, with a high torque output. In addition, the mechanical has been developed into two working models (passive and active) in order to overcome the intrinsic shortage of non-back drivability in ultrasonic motor. The result system enables the client to do extension and flexion rehabilitation exercises in two degrees of freedom (DOF) for each finger as well as one DOF motion on the thumb. Finally, experiment has been carried out to evaluate the performance of the device.

A new technique was developed to solve inverse kinematics based on quadratic minimization. Firstly the inverse kinematic problem was formulated as a quadratic minimization problem through the constitution of a quadratic objective function derived from quaternion based kinematic description, then a new technique is developed to solve the quadratic minimization problem. The iteration procedures of the new technique are organized in two main phases: compute the search direction based on dynamic system synthesis; seek for acceptable step along the search direction. Numerical examples showed that inverse kinematic solutions can be delivered in a robust and time-efficient way, to meet the requirements coming across in the application field of every daily living support.

A new interfacing device that enables intuitive operation of a wheelchair mounted robotic arm is proposed. Three kinds of physical signals: jaw movement, breathing strength and head movement are captured using this device, and then be used to drive motion primitives of robotic arm in an intuitive way. This device is designed to operate in a mouth-only manner, thus enables usage for the upper limb disabled. Experiments are also conducted making use of this device and wheelchair mounted robotic arm to complete tasks in activities of daily living.

This paper describes an operational support system to simplify removing objects from a building structure in demolition work using dual-arm construction machinery. An operator cannot recognize the manipulator movement visually when a target object is strongly restrained in an unmovable environment, so the operator continues large lever-operations for a while after the object has been removed. This could lead to a collision against the surrounding environment. An operational support in construction machinery filed requires the compatibility among efficiency, quality, and safety and the commonality among various operator skill levels. The proposed support system thus identifies the moment when an object has been removed and cancels any operational inputs to ensure safety work when generating intensive force applied to a manipulator, focusing only on the common physical phenomena. An object-removal flag is defined as a situation where force applied to the end-point of a manipulator decrease rapidly in which lever operation and hand load are detected. Demolition experiments are conducted using a hydraulic dual arm system. Result indicates that the displacement of end-effector after removal and the number of error contacts are decreased while decreasing time consumption.

This paper gives an overview of OpenVR, a software tool that is able to construct a virtual robot and its working environment from CAD source files. The virtual robot can be played with the same as a real robot by providing corresponding controller and sensor interfaces, thus contribute to the research of robotics in concept visualization, robot design, and algorithm and software development. General purposed algorithms are also given to simplify the effect for the execution of complex manipulation tasks. © 2011 IEEE.

This study aims to construct a handling and grasp control method by multi-fingered robot hand with soft skin for the precision operation of cylindrical tools. We believe that the key to the improvement of the accuracy of the tool operation is to use an additional grasping point to reduce the tool's posture fluctuation derived from the external force exerted at the tool nib. We focus two factors that cause the tool's posture fluctuation. One is the rotation movement of the tool around the axis between two contacts by finger-tips. The other one is the deflection of the soft skin. We propose the effective allocation of the addition grasping point from the view point of the reduction of the tool's posture fluctuation. Our control architecture is a customized combination of resolved motion rate control and hybrid control which maintains stable grasping and handles the tool along with the desired trajectory of the tool nib. It is validated through the physical tests using the actual multi-fingered robot hand that the accuracy of the tool nib trajectory is improved by proposed control method. © 2011 IEEE.

This paper proposes a practical framework for measuring the external force applied to a construction manipulator (front load vector) by using a hydraulic sensor. Such a force measurement system requires high accuracy and robustness considering the uncertainty in the construction machinery field, but it inevitably includes measurement errors owing to difficult-to-reduce modeling errors. Our framework thus adopts a relative accuracy improvement strategy without correcting the models for the practicality. It comprises (i) quantifying the internal error range (IER) by using the sum of the maximal measurement errors of static and dynamic friction forces, which change in postural and kinematic conditions, (ii) calculating the error force vector by using IER to select cylinders (sensors) that have less error, and (iii) outputting the front load vector using the cylinders whose error force vector is minimum. Experiments were conducted using an instrumented hydraulic arm. The results indicate that our framework can enhance the relative accuracy of external force measurement independently of various postural and kinematic conditions.

This paper shows the focused assessment with sonography for trauma (FAST) performance of a wearable tele-echography robot system we have developed that we call "FASTele". FAST is a first-step way of assessing the injury severity of patients suffering from internal bleeding who may be some time away from hospital treatment. So far, we have only verified our system's effectiveness under constantly wired network conditions. To determine its FAST performance within an emergency vehicle, we extended it to a WiMAX mobile network and performed experiments on it. Experiment results showed that paramedics could attach the system to FAST areas on a patient's body on the basis of the attaching position and procedure. We also assessed echo images to confirm that the system is able to extract the echo images required for FAST under maximum vehicle acceleration.

The purpose of this paper is to propose ultrasound visual servoing algorithms for controlling a robotic system equipped with an ultrasound probe for large pulsation and a displacement towards the out-of-plane of a US image.
In this study, we aim to develop a robotic system for detecting bleeding source based on the blood flow measured by using a non-invasive modality like an ultrasound (US) imaging device. Some problems related to the measurement error still need to be addressed. As the first step in solving these problems, we focused on the large pulse amplitude and displacement of the artery towards the out-of-plane of a US image, and developed US visual servoing algorithms to control the probe. We conducted preliminary blood flow measurement experiments using an phantom containing artery model and a manipulator equipped with a US probe (BASIS-1). The results present the first experimental validation of the proposed algorithms.

This paper proposes a practical framework for detecting (identifying the on-off state of) the external force applied to a construction manipulator (front load) by using a hydraulic sensor. Such a detection system requires high accuracy and robustness considering the uncertainty in pressure-based force measurement. Our framework is thus organized into (i) identifying the dominant error force component (self-weight and driving force) using theoretical and experimental estimation and binarizing the analog external cylinder force, (ii) evaluating detection conditions to address indeterminate conditions such as stroke-end, singular posture, and impulsive or oscillatory force and redefining three-valued outputs such as on, off, or not determinate (ND), and (iii) outputting the front load decision by combining all the cylinder decisions to improve robustness through priority analysis. Experiments were conducted using an instrumented hydraulic arm. Results indicate that our framework adequately detects on, off, and ND outputs of the front load in various detection conditions without misidentification. © 2011 IEEE.

The state identification framework we propose supports complex construction machinery operations using a dual arm. Such support requires compatibility with different types of support and commonality among various operator skill levels. Our framework is organized into (i) real-time task phase identification defined using joint load applied based on environment constraints and (ii) time-series attentional condition identification defined as an internal work-state condition classified by the operational support necessity level and dependent on the vectorial or time-series data selected by the identified task phase. Experiments are conducted using the instrumented hydraulic dual arm system for transport and removal tasks, including complex dual-arm operations. Results show that the number of erroneous contacts, internal force applied, and mental workload decreased without any increase in time, confirming that operational support based on our framework greatly improves individual operator work performance.

This paper reports a newly developed hydraulic dual robotic arm system to create and evaluate intelligent systems, which support complicated machine operations, for advanced construction machinery. This kind of machine system (test-bed) requires functions to quantify its dynamic characteristics and operational difficulty (influential factors). In particular, construction manipulator nonlinearly changes its dynamics depending on various internal and external factors. To quantify such influential factors, our proposed test-bed is equipped with standard hydromechanical system which includes two manipulators and grapples, and practical sensing system which detects control input, oil pressure, oil temperature, and cylinder stroke data. Using the developed test-bed, fundamental experiments were conducted to clarify hydromechanical system characteristics. Experimental results indicate that the test-bed quantifies its hysteresis, pressure loss, and time delay, and show that variable dynamics complicates intuitive and precise machine operations and external force measurement. This analysis confirms the developed machine system is useful to quantify influential factors for creating intelligent system.

The purpose of this report is to propose portable and attachable tele-echography robot system: FASTele. Focused assessment with sonography for trauma (FAST) is important for patients who have shock by internal bleeding. However, the patient has little time, and transportation to a hospital may take too long. A system which enables FAST more quickly is required. Therefore, we aim to develop a tele-echography (FAST) robot system that can be used by a paramedic easily for shock patient in ambulance or at injury scene. To develop the system, portability and usability (for paramedic) are significant issues. We developed a tele-echography robot system which has 4-DOF. The robot is attached to each roughly FAST areas of patient body (body-based set up) and remotely fine-tuned position by a specialist in a hospital. The robot can control the posture of probe by curvature rails. The mechanism that maintains passively the contact force between the probe and patient&apos;s body surface by using springs enables the robot small and lightweight. Feasibility experiments of FAST are reported.

Human-symbiotic humanoid robots that can perform tasks dexterously using their hands are needed in our homes, welfare facilities, and other places as the average age of the population increases. To improve the task performance of human-symbiotic humanoid robots, a motion-planning method with active body-environment contact was developed. Taking into account the positive and negative effect of mechanical passive elements implemented in joints, this motion-planning method can enables the hand-arm system to establish the active BE contact at the appropriate body-site and to select the joints that perform the movement for executing the given task. Control algorithms for the tool operation, namely, writing with a pen, were also constructed. The motion-planning method was validated through actual experiments on a prototype human-symbiotic humanoid robot.

The purpose of this report is to propose a diagnosis and treatment scenario by assistance of bystander and echography robot for trauma patient. Quick treatment is important for patients who have shock by internal bleeding. Therefore, focused assessment with sonography for trauma (FAST), which is a simple and quick diagnostic method, was developed as a first lifesaving step in a hospital. However, a shock patient has little time, and transportation to a hospital may take too long. Therefore, we aim at development of a system which enables FAST at injury scene by assistance of bystander. To develop the system, life-saving flow and a FAST device are significant issues. First, we constructed a diagnosis and treatment scenario. Then, we developed a tele-echography robot system which has 4-DOF that a bystander could attach. This robot is attached to each roughly FAST areas of patient body by a bystander and remotely fine-tuned position by a doctor in a hospital. In this way, a bystander may not do an exact positioning. In addition, the robot has a mechanism to generate contact force between echo probe and patient body surface by two springs. This mechanism not only fit in patient body motion but also reducing the number of controlled axis. To confirm the medical applications of the scenario and the robot, we performed experiments with some examinees and doctors. We confirmed effectiveness of the mechanism and that a bystander could attach the robot to each roughly FAST areas of patient body. We also confirmed that a doctor could do FAST with the robot by remote-controlled on the roughly FAST areas in approximately three minutes. These results show that the robot would enable FAST by assistance of bystander, and the scenario would make FAST faster than the time required transporting the patient to the hospital.

A methodology for setting the reference value of a grasping force when a multi-finger robotic hand grasps and lifts up an object without knowing its characteristic weight, coefficient of static friction, and stiffness was devised. The grasping force must be set to avoid dropping or deforming the object. To fulfill this requirement, the methodology measures object characteristics by detecting the moment of deformation or slipping according to the deflection of a mechanical passive element. The reference value of grasping force is set according to an upper limit to avoid crushing and a lower limit for lifting up the object calculated from the object's above-mentioned characteristics. The degree of the accuracy of object characteristic measurements was evaluated through experiments using an actual human-mimetic hand-arm system. Finally we validated that the system can pick up objects with the grasping force set by our methodology. ©2010 IEEE.

Human-symbiotic humanoid robots that can perform tasks dexterously using their hands are needed in our homes, welfare facilities, and other places. To improve their task performance, we propose a motion control scheme aimed at appropriately coordinated hand and arm motions. By observing human manual tasks, we identified active body-environment contact as a kind of human manual skill and devised a motion control scheme based on it. We also analyzed the effectiveness of active body-environment contact in glass-placing and drawer-opening tasks. We validated our motion control scheme through actual tests on a prototype human-symbiotic humanoid robot.

We newly report a tele-echo guided portable robot, FASTele-1 that assists early echo-diagnosis for wounded patients through long-distance. Especially, the robot will be used for primary diagnosis called FAST [Focused Assessment with Sonography for Trauma] looking for in-body spaces filled with blood caused by shock In addition, it can be attached onto the patients body even by novices without expert knowledge who encounters at the scene. Four degrees of freedom involving pitching, rolling, translational movement and adjustment for sticking to the body surface are given to it, A mechanical spring allowing stable contacts with the patient body surface is adopted to reduce an actuator and a corset enabling easily fitting to various body forms is used as a base part. Evaluation experiments indicating FASTele-1 enables to send Sonography of in-body cavity enough for FAST diagnosis by medical specialists in the separated area confirm the effectiveness of the proposed design method.

We propose a new locomotion rehabilitation RT device, PARTY (Perception-Assisting Robotics TechnologY) that enables the paralyzed to get a perception-bypass communication path via a non-paralyzed-part body for recognizing foot contact pressures on the paralyzed-side. Clinical tests for four patients indicate the locomotion rehabilitation system allow hemiplegia to improve the adjusting capability of foot pressure transitions on the usage of them.

Installation of passivity on the skin and inside joints of the robotic hand becomes a key-technology to remarkably enhance the stability of handling and manipulation. Based on this idea, in this paper a sophisticated mechanism design of TWENDY-ONE hands with mechanical springs in DIP and MP joints and whole-part covered soft skins is presented.

We developed a new simulator of operation skill training for Double-Front construction Machinery. As for a past construction machinery simulator, the one developed for a lot of educational for dangerous acknowledgment, and to train the operation skill is few. It was simple digging work by the backhoe, and work of the crane. In this research, Double-Front construction machinery which we make a target increases the number of fronts should be manipulated and demands an advanced operation skill. Moreover, the discretion dismantlement and the disaster relief and restoration are developed as assumption work as for Double-Front construction machinery. It is understood that the meaning of the developed simulator is high from these two points. As a result of the proof experiment, we obtained data with a different in the feature transition of expert and beginner's end-effecter orbits. Because the difference was confirmed, it becomes useful as a training machine for the skill improvement by being analyze this in the future and feeding back to the operator appropriately.

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.

In this paper, we describe the design method of an anthropomorphic 4-DOF tactile interaction manipulator with mechanically passive joints giving robots to accomplish high performance force-following and tactile-based contact state recognition despite physical interference and contact with humans occurring at links and at joints. The shape and appearance of this manipulator was based on statistical data on the Japanese male physique to allow for human-like contact interaction recognition. Joint are passively compliant, consisting of a mechanical leaf spring and rotary damper giving the manipulator high passivity. Cylindrical or spherical surfaces of the body including the elbow and wrist are overlaid with distributed tactile sensors acquiring accurate contact information. Evaluation experiments indicate that the manipulator provides high performance of force-following and tactile stimulation measurement, during physical interference and contact with humans and confirmed its effectiveness in improving human/robot symbiosis.

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.

In this paper, we propose a design method of human-symbiotic humanoid robots with whole-body compliance composed of mechanical and controlled compliance, for securing a wide range of dynamic responsiveness to various types of physical interference with humans. First, a design idea of mechanical compliance for realizing quick reduction of impulsive force is described, incorporating softly deformable materials attached on the body surface and passively compliant joints equipped with a mechanical spring inside. Next, we propose a cover sensor that detects accurate external force vectors on the entire body surface, in order to generate whole-body compliant motions based on the tactile and force information detected. Finally, evaluation experiments of physical interference between humans and an actual anthropomorphic robot are presented to verify the effectiveness of the respective compliance. The results confirm that two measures for securing whole-body compliance faculty realize both quick and slow responsiveness to physical interference with humans and that the proposed method is useful for enhancement of human-robot coordination.

In this paper, we herein describe force detectable surface covers for humanoid robots to realize naturally physical interaction with humans. The covers can detect various tactile and force information, such as accurate external force vector and contact positions, from a widely range of the robot body surface. First a basic surface cover structure composed of a force-torque sensor and several touch sensors is proposed. Next, we present a design method to implement such a cover structure onto dual arms of an actual humanoid robot. Finally, from basic experiments for verifying the characteristics of the proposed force-detectable surface cover systems, it was confirmed that high measurement accuracy of a contact position and force vector is accomplished. In addition, from an application experiment, where some humans actually occur physical interference with an actual humanoid robot overlaid with the covers, it was confirmed that the capability of the covers' sensing even several contacts on several parts of robots' body is effective for realizing high level human-robot symbiosis.

In this paper. Ire herein describe the control methods used for a humanoid's compliant behavior following human force and motions while fulfilling given tasks under various constraint conditions during physical Interference (PIF) with a human. PIF is a form of physical interaction viewed from the robots point of view.
in cases of PIF occurrence, PIF Adapting Behaviors for attenuating physical influences caused by PIF on both a human body and a robots' task are required First a base control method for compliantly following PIF by coordinating multiple joints of the arms and trunk is presented By utilizing this method PIF force produced on several areas of the robot's entire body is efficiently reduced Next, the control methods for fulfilling git en tasks, as well as following PIF at the same time, are proposed rn these methods, the idea is incorporated that if the utilization of redundancy is needed for task fulfillment or constraint conditions and attributes of the given task are changed, the role of each joint needs to change as well. Adapting to the diversity of task attributes and also the necessity of utilizing redundancy, the proposed control methods enable the robots to realize both force following and task fulfillment at the same time. Finally from the evaluation of the experiments, it vas confirmed that the proposed methods realize a humanoid's capability of compliantly adapting to human motions while fulfilling tasks by efficiently utilizing redundancy.

An objective of this study is to find out design requirements for developing human symbiotic robots, which share working space with human, and have the ability of carrying out physical, informational, and psychological interaction. This paper mainly describes design strategies of the human symbiotic robots, through the development of a test model of the robots, WENDY (Waseda ENgineering Designed sYmbiont).
In order to develop WENDY, mobility and dexterity of a humanoid robot Hadaly-2, which was developed in 1997, are improved on. The performances of WENDY are evaluated by experiments of object transport and egg breaking, which requires high revel integration of whole body system.