Recently, falling down accidents of elderly people tend to increase along with aging society. The major factor of falling down is a gap of the center of balance due to decline in physical performance for aging. To prevent falling down accidents, we began to produce walking training system that in daily use and stress- free as possible. In this study, we produce High-Performance Shoes that can shows the status of walking balance. As the device to present the status of walking balance, we use an android tablet and an android-powered head mounted display. Further we create an android application for presentation of status of walking balance in real time.

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Gait training is important for rehabilitation of challenged users but it requires a large space and support persons. Until now, we have developed the automatic speed-controlled treadmill. But we could not safely conduct experiment because we don't have any safety device. In addition, many of the elderly are in need of body weight support. Therefore, we developed the sensor frame capable of body weight support and conduct gait analysis of healthy people with the automatic speed-controlled treadmill and the sensor frame.

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A proper seating is important as an aid for cerebral palsy patients, and has good influences on patients' physical conditions and mentalities. Deformity of spine causes gaps between their backs and backrests of wheel chairs. Generally, urethane cushions are used to fill up the gaps. However, this method cannot handle their dynamic motion that will happen in daily life. In the previous study, we developed the first prototype of the intelligent seating system by using a conventional adjustable-belt type seating and some air bags on the belts. We could control the posture and pressure of users, but there is a severe limitation for real situations. In this paper, we propose to use an adjustable sheet mechanism for the wheelchair seating. The adjustable sheet mechanism is very simple and a combination of a main sheet and adjustment belts. We installed this mechanism in the conventional adjustable-belt type seating. For convenience of the adjustment, we also developed a back-shape measurement system and proposed an adjustment method on the basis of the measurement results. Finally, a validation test was conducted and evaluated. The experimental result indicated that the adjustable sheet fit to the complex back shape and controlled a good posture and even pressure for a dummy deformed backbone.

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This paper reports our developing sit-to-stand support system using ground reaction force to operate device. Our device is controlled by information of the user grand reaction force (GRF). In this system, the user don't need to operate the switch or button and is given suitable and dynamic assist according to user lower limb power. In this presentation we show first prototype device and describe about device control rule, experiment results and the found problems of control. Next, experiment device for new version to solve these problems is shown. This device use for analysis of support trajectories. The support trajectories were decided by sit-to-stand experiment and other discussion.

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This paper presents a new control method for absorbing impact forces exerted on the tip of a multi-joint robotic arm. In this method, integral controller for generating virtual desired trajectory is hold at the time of impact. We show that the impact force can be absorbed extremely by using the simple control algorithm. In addition, we show that the tip of the robot is forced to move against the applied force in case of lack of the hold operation of integral controller, and resulting in unexpected recoil due to antagonistic nonlinear springs.

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This paper presents an identification process of viscoelasticity of a revolute joint of a simple one-link robot. This revolute joint has no viscoelastic property in itself due to a pully or a ball bearing incorporated in the joint axis. However, there exists virtual viscoelastic characteristic in the joint by placing antagonistic mechanism made with a pair of pneumatic artificial muscles. In this paper, first we generate contraction forces by applying compressed air to the pair of artificial muscles in order to maintain initial orientation of the robot and to increase joint stiffness. In that situation, an external force is applied to head of the joint so as to ingenerate 7°-rotational angle. Subsequently, slight vibration of the joint is caused by the release of the external force. By applying non-linear least-squares method to the joint angle data obtained from the vibration, virtual viscoelasticity of the joint can be easily identified. Finally, we reveal the existence of linear and non-linear properties of viscoelasticity according to the amount of the contraction of artificial muscles.

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Wire-actuated platform is a parallel mechanical system consisting of a platform and a number of length-adjustable wires. In order to deal with an inverse kinematics of this mechanical system, we have to take account of static conditions due to the conspicuous characteristic of a wire that it only can hold a tensile force. In this study, we deal with a formulation and a solution procedure that take account of the static conditions as well as a multi-world situation that can occur as the result of a kinematic motion of the platform. Simulation results of its motion based on the proposed inverse kinematic approach are also demonstrated.

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Pole vault is an interesting task because of its high performance using a large elastic element. Although previously we showed that active bending motion is effective to improve pole vault height, it was sensitive to disturbance. In order to stabilize pole vaulting performance, physical feedback is important because of its quick response. Therefore, we focused on musculoskeletal system, especially its bi-articular spring-damper system, and investigated its contribution to stabilization of pole vaulting. We compared pole vaulting performance of a non spring-damper model, a mono-articular spring-damper model and a bi-articular spring-damper model in simulation on the disturbed condition. As a result, we found that the mono-articular spring-damper model and the bi-articular spring-damper model tended to be reduce negative effect of large disturbance at early timing of pole bending motion. In addition, bi-articular spring-damper model had intermediate response characteristics to disturbance between other two models. These results implicate that musculoskeletal system contributes to stabilize pole vault.

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We have studied hands-free interface using head motion that enable to access both the real world and PC in order to support the gesture of the disabled and bedridden patients. In this paper, we extend the accessible range to 3D by introducing 3-dimensional kinematics and its coordinate system, and modify the pointing speed determination function in order to improve the access speed. In addition, we propose a new performance index to evaluate operability corresponding to the 3-dimensional space access. Finally, we experimentally confirm the effectiveness of the proposed method by some evaluation tests as for the pointing ability and the robot operation.

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This paper proposes a wheeled walking assistive apparatus that assists a person with hemiparesis. This device has high stability comparing with leg types because its wheels always contact on the ground. In addition the user does not need to support the weight of it. The user wears the device bending his/her hemiplegic knee. Differential gears provided between front wheels enable the user to rotate in the horizontal direction. The gas spring attached on rear wheels enables the user to tilt the device forward easily. We propose the controlling method for this apparatus based on the tilt angle that is measured by a gyro sensor and acceleration sensor when travelling. Results obtained from experiments demonstrate that non-disabled persons can travel stably indoors.

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Japan entered a super-aged society, and an excretion care of nursing care is a serious social problem. The excretion care causes physical and mental stress to both caregivers and recipients. In this study, we have been developing a new nursing care equipment for reducing the stress of the excretion care. The equipment consist of "Support system" and "Toilet system". The support system assists the recipient to get up from a bed and walk without help, and the toilet system assists of toileting. The toilet system can capture feces, prevent odor dispersion by adhering tightly to the buttocks, and automatically wash an anus. This paper describes the general appearance of the toilet system, the details of a toilet unit which is some of the toilet system, and washing function of the toilet unit of estimation.

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Sleep monitoring systems that can be used in daily life for the assessment of personal health and early detection of diseases are needed. We are developing a system for unconstrained measurement of the respiration and heartbeat of a person on a soft rubber-based tactile sensor sheet. To extract faint heartbeat signals from pressure detected by the tactile sensor, improvement of the S/N ratio is needed. This process takes some time, and can be conducted at only a limited number of locations on the sensor. The suitable locations for the heartbeat detection depend on not only the location but also the lying posture of the person on the sensor. We propose a method for detecting the lying location and posture using a pattern recognition technique based on machine learning. In this paper, we describe the method and report the experimental results.

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This paper proposes a three D.O.F completely restrained parallel wire robot with four motors which enables fast three D.O.F positioning. The control of orientation for the end-effector part by the conventional three D.O.F completely restrained parallel wire robot is impossible. Because, the motion D.O.F by four motors is used only for three D.O.F positioning without considering the orientation of the end-effector part. The end-effector part of the mechanism should move keeping horizontal orientation when considering actual tasks such as pick and place. The characteristic of keeping with horizontal orientation has been realized by "rigid type" parallel link robot such as Delta robot. This paper proposes a new mechanism to realize the characteristic keeping with horizontal orientation for three D.O.F completely restrained parallel wire robot. By using parallel paired wires for one motor, the end-effector part always moves with keeping horizontal orientation for any positioning point in the work space of the robot.

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A large scale parallel wire-suspended robot realizes a three dimensional positioning mechanism with simple and light weight using multiple wires. A suspended object of the mechanism can be manipulated freely in large workspace. The large scale wire robot has a characteristic of generating wire's sag. Therefore, a dynamical model considering the wire's sag is important when controlling the suspended object. The 3-D positioning wire suspended mechanism can be constructed by three wires. When adding one more wire for the mechanism, the mechanism has redundant D.O.F. which can be used to increase rigidity of the mechanism. The redundant type of the wire-suspended robot is analyzed only the case of the wire's sag modeling. The study proposes the modeling considering wire's sag. Then the wire-suspended robot with four wires is analyzed in the view point of using the redundancy of wire length. The study also proposes how to control the redundant wire's lengths.

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In tendon-driven mechanism, the relation between the motion of each actuator and each joint is complex because of its dependency on its tendon routing and moment arms. We propose the mechanism to solve this complexity composed of step pulleys and moving pulleys, and we call it as tendon inverse mechanism. Furthermore, we can control the joint stiffness independently by using non-lenear elastic components because of this mechanism. In this paper, we introduce the methodology to construct this mechanism and validate it through some experiments.

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In this research, we propose a 2DOF joint of quadruped robot that can dislocate to protect the robot from overload. Proposed 2DOF joint can dislocate with excess load from arbitrary orientation. The design specification is determined by motion analysis of a dog. By using this 2DOF dislocatable joint, we designed a leg of quadruped robot. The Structure of the prototype and fundamental operation of the movement is reported.

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This paper proposes an electric wheelchair that realized traveling on uneven environments and standing. The proposed wheelchair allows a caregiver to reduce their burdens and a user to improve QOL. Conventional electric wheelchairs have mainly three problems: medical problems sitting for a long time, a psychological problem due to the low position of eyes, and low traveling performances on uneven environments. The proposed wheelchair consists of a link mechanism powered by a gas spring for changing its posture and a traveling mechanism with a part of caterpillar and a flipper arm for uneven environments. This paper presents the concept design and the experimented results of standing and stair climbing using a scale model wheelchair, which confirms the design effectiveness.

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In this study, in order to improve the operability of a myoelectric prosthetic hand, a sensory feedback device, which is attached on an upper arm of operator by a belt, was developed. First, contact force is detected by two pressure-sensitive sensors installed on a finger cushion of the myoelectric prosthetic hand. Then, when the finger of the myoelectric prosthetic hand holds a subject, the belt of the device is wound by a motor and tightens operator's upper arm. Thus, the operator gets the sensory feedback. By changing the speed which winds the belt, the operator can feel three kinds of hardness for objects, which are hard, intermediate and soft. The distinction experiment of hardness and the holding experiment of potato chips were carried out, and the validity of the proposed sensory feedback device was verified.

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In this paper we describe a motion control of the mobile robot to support Home Oxygen Therapy patients' going out. We propose a guidance type mobile robot which moves ahead of the user. Force sensors are adopted to sense the input force from users, and the sensed signals are used for control the robot's motion. 2 D.O.F. control system is adopted for the robot's controller to adjust the operational response between the user and robot. Then the effectiveness of the control system is verified by some experiments with a prototype robot and HOT patients.

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In this paper, we propose an assistance system for an old aged person to support his/her standing-up motion from a chair or a bed with inducing them to be a certain posture. We think the certain posture is the posture of tilting the body toward one side, because generally we are comfortable with our posture of using armrests or standing on one leg. First, we examine how much tilting body support load to the knee. Finally, we develop the mechanical system to moving one side of armrest and examine our system.

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