As aging population grows, robots used in welfare and healthcare domain such as social robots, assistive robots and service robots (hereafter Welfare Robots, WR) has been attracted more attentions as one of the solutions to the welfare resource shortages. However, at present, WR have not necessarily implemented or embedded widely in society. Reasons for hindering WR provision to our society include the absence of clear assessment criteria and social implementation process models. While some care institutions and private homes promoted and integrated WR successfully, large part of our society have struggled to identify ways of appropriating the WR provision. Based on the investigation on seven successful organizations on evaluation and implementation practices, the research extracted key aspects for WR provision in society. The extracted three key categories with seven aspects highlights importance of standard assessment framework which includes stakeholder involvements and concepts of care recipients' autonomy. These critical aspects of WR provision contribute to better WR design, development and implementation in society under the new normal.

Robotic devices for nursing care are expected to help caregivers work with the elderly. Some robotic devices assist in the physical transfer of the elderly, and these robots come in contact with large surfaces of the human body. The regions of the buttock and the back may be uncomfortable due to these robotic devices. Therefore, sensing devices simulating a human buttock were developed to quantify and evaluate the load of a human body objectively. This buttock dummy consists of simulated bone and soft tissues, which include muscle, fat and skin. These regions have multi-Axis force sensors to enable the quantification of the load due to the robotic devices used for nursing care. On measuring the soft exterior, it was found that the stiffness of the buttock dummy was similar to the human buttock. The comfort of a robotic bed was measured using the buttock dummy, and it was found that the shear force increased due to the deformation of the robotic bed. Thus, it was proven that the buttock dummy was capable of measuring the load of the human body when being used with robotic devices for nursing care.

Aiming to eliminate a labor shortage caused by the aging of society, many kinds of service robots are under development. Nursing care for the elderly is considered as a typical application of service robots, especially in Japan. Elderly care robots or robotic care device must be designed with safety, but not a few manufacturers are inexperienced in designing and manufacturing them on the basis of safety. In this paper, we introduce a risk assessment assistance tool for robotic care device targeted for inexperienced manufacturers of risk assessment.

Motion analysis of human body is indispensable for design and evaluation of assistive technologies. Especially, on-site analyses, which are conducted not in experimental environments but in life circumstances, are important to develop truly beneficial assistive technologies. We developed a portable motion tracking system using high-accuracy AR markers. It enables easy measurement of 6-DOF (six degrees of freedom) motion of multiple tracking points by a single camera. The pose estimation errors are about 5 [mm] in location (depth) and about 2 [deg] in orientation. We applied the prototype of the motion tracker to the on-site motion analysis tasks, and demonstrated its availability in the evaluation of assistive technologies.

Human-cooperative robots (HCRs) are expected to benefit various fields. Safety functions are essential to the control system of HCRs because their hazardous movements after a system failure may cause serious injuries to operators. Therefore, their reliability must be sufficiently high relative to the estimated risk, and it is important to design a suitable safety function for the control system to match the safety level required for an HCR. We propose a methodology of safety-function design for the control system of an HCR and attempt to effectively combine design approaches for hardware and software of safety-related systems (SRSs) on the basis of the concept of functional safety. This study describes the details of the methodology for an HCR that we adopted as a platform system. First, SRS hardware with a dual-channel voting architecture was designed, and then, functional safety analysis was performed to verify whether the hardware satisfied the required safety integrity level (SIL). Next, SRS software with diverse programming, which is recommended for the required SIL, was designed by utilizing a disturbance observer. Finally, experiments were conducted on the SRS for representative failures and the safety function was verified for the control system, as set by the proposed methodology.

This paper presents a basic study on feasibility of usage of humanoid robots as an evaluator of assistive devices, by taking advantage of its anthropomorphic shape. In this new application humanoid are expected to help evaluation through quantitative measures, which is difficult with human subjects, and also to reduce the burden coming from ethical concerns with costly tests by human subjects. Taking a passive supportive wear "Smart Suit Lite" designed to relieve the load at lower back as an example, we have conducted pilot experiments by using the humanoid robot HRP-4C. The motion to be performed by the humanoid is obtained through retargeting technique from measured human lifting motion. The supportive effect is first estimated by simulation taking into account the mechanism of the supportive device. The experimentation of humanoid hardware brought us encouraging results on the basic feasibility of this application, as we observed a clear decrease of the torque for lifting when wearing the device as expected by the simulation.

Robots need to be dependable to work closely with humans. Further they must be accountable for the system design and development process. This makes some of the safety related standards such as IEC61508 adopt module based architecture and model driven engineering process. On the other hand, module-based architectures using middlewares are popular in the integration phase, when developing robot systems. To elaborate the behaviors of realtime control modules, IEC61499 function blocks derived from PLC languages is useful. Therefore, in this paper, we combine them and present a development process consisting of system design in SysML, elaboration in function blocks and integration using RTMSafety, which is an implementation of RT-middleware for the use of safety-related systems. We also show an example system for a dual-arm robot intended to work with human workers.

Recent years have seen an increase in demand for robots that work closely with humans, or operate at disaster sites. These robots need to have high dependability. At the same time, the idea of system development based on standards is becoming important especially in the field of embedded systems including robots. IEC61508, which is a standard of functional safety requires the V-model of the engineering process and keeping the documents and programs of each phase consistent.
However, this process costs a lot and freedom still remains about the choice of tools to support the development, the way of describing specifications/programs in each phase and so on. This makes consideration of the concrete development process and the tools used there before starting an actual development important. Accordingly, the purpose of this paper is to present a concrete architecture and a development process that is IEC61508 ready. We especially focus on the software aspect and mention related standards as well.

We have been developing a passive motion exercise system for ankle dorsiflexion/plantarflexion that can be applied to patients with complicated ankle joint deformity. The developed system is expected to reduce edema in lower limbs, and currently we are aiming to find objective indicators for volume of edema by the use of our system. In this paper, the effects of passive motion provided with an ankle dorsiflexion/plantarflexion exercise system on peripheral circulation are examined. The result indicated that skin blood flow and surface skin temperature of the elderly subjects changed associated with passive motion, which suggests that decreased peripheral circulation can be improved with passive motion. © 2011 IEEE.

As technology advances in robotics, studies of assistive robots and service robots are actively conducted, aiming at practical use of them. Occasions for demonstration experiments increases accordingly, however, awareness of protection of subjects is not enough. This may bring risks to the subjects. Therefore, ethical reviews by Institutional Review Board become more and more important. In this paper, framework of ethical review process and subject protection in developing assistive robots for care-giving is described with an example of the study of the excretion care robot "Toilet-Assist," where the subjects in the demonstration experiment were different from the people involved from the ethical viewpoint.

This paper proposes a new method for excretion care by use of robot technology. Excretion care is one of the most burdensome tasks in care, along with bathing care. Among the problems related to excretion care, transfer of the care recipient between a wheelchair and a toilet is the most acute problem.
Therefore, we proposed a new transfer method for getting rid of twisting the coupled bodies of both a caregiver and a care recipient by replacing a wheelchair and a toilet automatically while the care recipient is keeping his/her standing position. Experimental results showed that the proposed method was expected to reduce the physical burden of the caregiver during excretion care.

We have been developing a passive motion exercise device for ankle dorsiflexion/plantarflexion that can be applied to patients with complicated ankle joint deformity. In conventional ankle motion exercise devices, a footplate remains parallel to the axis of ankle dorsiflexion/plantarflexion. This may cause pain by forcing the ankle position to fit in the device and may also cause uneven contact of the sole to the footplate during the exercise. Therefore, we proposed to make a device which enables passive dorsiflexion/plantarflexion movements of ankle with adjustable inversion/eversion.
In this study, the effect of passive joint of inversion/eversion is examined using pressure distribution on the footplate.

In Japan, robotic systems for rehabilitation or assistance of the elderly and the disabled people are actively studied recently. In developing rehabilitation/assistive robots, safety is one of the most important issues, since the robots work very closely to the users or worn by the users. Parallel wire mechanisms have Prospects of giving Solutions to safety issues on rehabilitation robots. In this paper, the author takes a look back on her studies on motion assist devices using parallel wire mechanisms and discusses advantages and disadvantages of the motion assist devices using parallel wire mechanisms.

We proposed and have been studying a multiple-dof leg rehabilitation system which employs a wire-driven mechanism. Using a parallel wire mechanism, multiple-dof motion can be achieved with relatively low powered actuators compared with the mechanisms that use conventional rigid links. Also, since wire-driven mechanisms are light and flexible, it makes the system human-friendly. Our eventual goal is to develop a rehabilitation system that carries out 6-dof motions of hip, knee and ankle joint. In order to achieve this goal, we are taking a gradual approach. In this paper, we describe a 2-dof experimental system which we designed and built. Target motions of the 2-dof system are flexion/extension of both hip and knee joints. We also mention a 4-dof experimental system which was built by extending degrees of freedom of the system. Target motions of the system are hip joint flexion/extension, hip joint abduction/adduction. hip joint external/internal rotation, and knee joint flexion/extension. Experiments showed that the multiple-dof joint exercise can be carried out using the proposed system.

We proposed and have been studying a multiple-DOF leg rehabilitation system which employs a wire-driven mechanism. Using a parallel wire mechanism, multiple-DOF motion can be achieved with relatively low powered actuators compared with the mechanisms that use conventional rigid links. Also, since wire-driven mechanisms are light and flexible, it makes the system human-friendly. Our eventual goal is to develop a rehabilitation system that carries out 6-DOF motions of hip, knee and ankle joint. In order to achieve this goal, we are taking a gradual approach. In earlier studies, we built and tested a single-DOF experimental system and a 2-DOF experimental system. Currently, we have built and are testing a 4-DOF experimental system. Target motions of the system are hip joint flexion/extension, hip joint abduction/adduction, hip joint external/internal rotation, and knee joint flexion/extension. In this paper, we describe an overview of the 4-DOF experimental system. We also mention experiments using the experimental system.

We propose here a new type of leg rehabilitation system. The aim of the system is to realize multiple-degree-of-freedom (DOF) training of a leg by manipulating the patients leg by wires. A single-DOF experimental system was built and tested, and the experimental results showed the feasibility of a wire-driven leg rehabilitation system. Next, a 2-DOF experimental system was designed, with a target motion of flexion/extension of both the hip and knee joints. Experiments of single-DOF motion on a test dummy and a male subject showed that the system generates enough accurate motion to support range of motion exercise. In addition, the results showed that the wire-driven mechanism would be a human-friendly system.

The purpose of this paper is to evaluate the physical and mental stress based on the physiological index, and a new evaluation method of heart rate variability is proposed. This method combines the wavelet transform with a recurrent neural network. The features of the proposed method are as follows: 1. The wavelet transform is utilized for the feature extraction so that the local change of heart rate variability in the time-frequency domain can be extracted. 2. In order to learn and evaluate the different patterns of heart rate variability caused by individual variations, body conditions, circadian rhythms and so on, a new recurrent neural network which incorporates a hidden Markov Model is used. In the experiments, a mental workload was given to five subjects, and the subjective rating scores of their mental stress were evaluated using heart rate variability. It was confirmed from the experiments that the proposed method could achieve high learning/evaluating performances.

This paper describes a walking control scheme for a quadruped robot. In conventional walking control scheme, the leg motion is generated from the robot moving trajectory beforehand, and it is difficult to control in real time. The proposed control scheme employs a real time command from a human operator. The operator gives a current planar moving velocity command to the robot. Since the command in the future cannot be predicted, the scheme does not generate a periodic gait. Body propulsive action is basically continued according to the command unless a problem arises. When a foot reaches the border of the work space of the leg, the body propulsive action is interrupted, and a supporting foot pattern is changed according to the leg transition rule. That is, a foot arrival at the border is considered as an event to trigger an recovery action for the body propulsion. The actions are decided to converge to the intermittent crawl gait when straight walking command is continued. The proposed control scheme is evaluated using actual walking robot.

In developing service robots, safety should be considered carefully since robots share the space with people who do not have technical background on operation of robots. Powered orthosis is one of the most severe examples.
We have been studying an upper limb motion assist system. The aim of the system is to help a disabled person move his/her arm by his/her own will by hanging the arm with strings and changing the length of each string. We have built an experimental system to examine the motion obtained with this system.

This paper describes the measuring method of the soil and soil model for automated excavation. The measuring method of the soil uses reactive force data which is detected when the manipulator touches the surface of the soil and position data of end effector. From these data, the shape and the hardness of the soil are estimated. The soil model predicts the reactive force of cutting. The cutting process is devided into two stages ; the initial state and the steady state. Different models are adapted to these stages. Experiments are made to show the effectiveness of the model.