Many elderly people suffer from decreased motor functions. The elderly might refuse to move beyond their ability due to fear-avoidance in physical therapies. To improve the situation, a training system of the standing-up motion is proposed. The system can measure state of the elderly and provide sensory feedback according to measured state. The system enables users to know their current and target state. This paper shows a design of the system and required parameters to utilize it effectively.

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"I would like to ride on a bicycle." is one of the requests from the patients in the post stroke rehabilitation. However, sufficient space and supporting therapists are required for the rehabilitation training. To solve these problems, bicycle simulator for rehabilitation has been developed. The system consists of a bicycle, a control computer, a visual system and a sound system. It can provide simulated scenery to the user and she/he can ride on a bicycle in the virtual world for motor and cognitive functional training. Training on the bicycle simulator is not only to achieve functional recovery but also to improve patient's quality of life and independent life by ensuring the transportation.

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Aim at safety and maneuverability, this paper proposes a semi-autonomous control of cycling wheelchair by steering power assist. In this study, a dynamic window approach is utilized to be the theoretical basis of navigation, steering power assist by servo motor is utilized to realize the actual maneuver. The proposed control scheme is implemented oil a mobile robot, its effectiveness is assessed by experiment.

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Although The ALS patients usually use the augmentative and alternative communication tools to communicate with other people, the assessment the tools which includes the selection of input switch is very difficult. In this study, we developed a novel device to measure the physical ability of patient to operate the input switch with push lever.

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This paper presents a method for a robot to handle tofu which is an example of non-rigid object to serve in a meal support system. The robot is equipped with a laser range finder (LRF) and a spoon holding manipulator. The LRF measures the 3D coordinates of surface points belonging to tofu on a plate. Then the system determines the position of tofu surface to scoop, and the manipulator moves according to the calculated trajectory. The system has an advantage that preparation of tofu cutting in bite-size is not needed. A preliminary experiment showed the effectiveness of the proposed method.

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An active orthosis, called powered glove, is under development to provide pinching function to cervical cord injury patients. The ortotic part of this powered glove system is a leather glove that has drive strings which work like human tendons to flex/extend fingers. The tension of drive strings is controlled by a controller based on user's command. The command signal is obtained by a belt shaped interface fixed on user's head. This interface detects activity of temporal muscle which works to close a jaw. Therefore the user can operate the powered glove through gentle chewing. A prototyped glove system is applied to two cervical cord injury patients and tested how well the powered glove can improve upper limb ability of cervical cord injury patients by providing pinching function. It is observed that the prototyped glove system extends upper limb ability of both patients through the evaluation test.

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Recently, robots rescuing or probing instead of human in dangerous places such as scene of a disaster are developed. In such an environment, it cannot respond to all irregular terrain by the move mechanism of a wheel type or a caterpillar type. Therefore, we paid attention to a legged robot. And, in this study, we use pneumatic artificial rubber muscle as an actuator of the legged robot. It contracts by air pressure and this actuator has flexibility, lightweight, and high-output density. We developed a leg of a hexapod robot, which is the parallel linkage mechanism using the straight-fiber-type artificial muscle. By this structure, structural posture maintenance was enabled, and higher bearing power was realized. Moreover, the theoretical formula of the leg including the characteristics of the artificial muscle is developed. And we guess that the theoretical formula reproduces experimental result. Furthermore, we propose about the design of a hexapod robot.

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Time optimal control method for quadruped walking robots are developed and installed into a practical robot system. As the fastest trot walk has already been obtained by our previous study, a method for obtaining the fastest walking pattern applicable to the transition between the rest state and the fastest trot walk state is proposed and its effectiveness is verified in this paper. The developed method here is also available for obtaining the fastest walking pattern between two arbitrary states. From the simulation and experiment, the effectiveness of the developed control algorithm is verified.

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A new Twin-Frame mobile robot, "ParaWalker-V", has been developed in this research, which acquires both mobility and manipulability with reduced-DOF. This robot would have several gait patterns for its locomotion. Some examples for static gait are proposed and verified them by walking experiments using developed mechanical model.

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In this study, we have developed a biped walking robot, which is used only a few actuators at torso, and use upper body dynamics. We have proposed walking model using two DOFs, and have shown walking motion by simulation. In this paper, a prototype robot is shown, and the control theory is indicated. The prototype robot conducts the stepping motion by side swing of upper body, and walk by swing back and forward in synchronization with the side stepping. Finally, we have verified by results of walking-experiment using developed prototype robot that it is possible to walk with the same method as a simulation.

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In this paper, we propose a cm-order legged robot that can climb and descend various vertical surfaces. For initial surveillance and inspection, distributed operation by many small and cheap robots is more available than that by a large and multifunctional robot. However, for a cm-order robot, rough terrain with small irregularity is equivalent to a big slope or vertical surface. Here, we developed a hexapod robot with length of 8.3 cm and weight of 11.5 g, which has claw feet for wall climbing and descending. The robot realized concrete wall climbing with a velocity of 0.7 mm/sec and the descending with a velocity of 1.22 mm/sec.

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The purpose of this research is to evaluate quantitative efficiency of power assist device by calculating muscle fatigue quantitatively. In this paper, we propose the efficiency quantitative evaluation method of power assist device by using the continuations wavelet transform of surface electromyogram (SEMG). The proposed method can measure muscle fatigue characteristic by calculated instantaneous median frequency of SEMG. We evaluate Muscle Suit^<[○!R]>R which is a power assist device for waist motion. SEMGs of erector spinae, rectus femoris and biceps femoris muscles of 10 healthy men subjects are measured while subjects take up and down a weight until they cannot continue such motions w/o the power assist device. Only erector spinae muscle fatigue is significant reduced (56%) in case of the power assist device used. The experimental results suggest that the proposed method can evaluate the efficiency of power assist device quantitatively.

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Swallow is one of the crucial functions for human living, but the number of the patients with dysphasia is increasing. The mechanism has not been elucidated so far, because swallow is a very fast reflex action that happens inside the body. These days, instruments for observing swallow have been developed, for example, Cine MRI, X-ray video, and endoscopy, and they supply the fundamental information to analyze it. And it is necessary to verify the information that Cine MRI and X-ray video supply from mechanical point of view because we are not able to understand the powers or the movements of muscles from only images of Cine MRI and X-ray video. Therefore, we are developing the prototype of swallowing robot. In this paper, the analysis results by Cine MRI and X-ray video, and the organs form cavitas oris of the swallowing robot to that is made to verify them is presented.

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The progress of space development has enabled astronauts to stay for a long time in space. One problem with long-stay in space is an elimination issue. Collecting feces in microgravity environment, Odor and Noise of exhausting odor fan in space ship is elimination issue in space. In addition, elimination in space is similar to the problem of elimination of the bedridden elderly person and motion-impaired person. For example, difficulty in defecating by muscle weakness is the problem. This study is to develop new toilet system can be excreted comfortable in the field of nursing care and space environment, and in order to verify its capability, to develop Defecation robot, that is recreate the human organ involved in elimination and the act of human defecating. This report describes the verification experiment of the developed new style toilet and measurement of the human buttock.

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This paper presents "an Active walker for adults", which can assist standing up and walking motions with stand-alone device. It consists of lead screw mechanism for standing up and long leg brace for walking which has two degrees of freedom for each leg. In order to relieve the burden of nursing care and simplify the rehabilitation in acute phase, it is worn and adjusted easily with the patients sitting on this device. In this paper, we report the mechanism of an active walker and utility of motion assist functions of this machine.

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A rideable autonomous mobile robot TAKAO 2 is currently under development in our laboratory. The robot is aimed at functioning in various human-robot-environment interactions and is developed on the basis of the system architecture of a non-rideable autonomous mobile robot TAKAO 1 developed earlier. The function of environment recognition and the function of self-localization are shared between TAKAO 1 and TAKAO 2. The safety for human is of major importance to develop the rideable robot. Hence the robot has a structure based on safety measures and will be embedded with an interface for human intervention. As part of experiments on the robots, some tests of the above-mentioned functions have been performed. This paper presents the development concept, the control system, the experiments of environment recognition and self-localization using TAKAO 1, and the design and the preliminary experiment of newly-created TAKAO 2.

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It is important to choose the right pillow height in order to have smooth turn over motions and a good sleep quality. In our previous works, we studied on the effects of pillow height on turn over motion, based on motion capture data. In this paper, aiming to simplify measurement, turn over motions are measured and analyzed using 9-axis motion sensors, under several conditions of the pillow height.

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In this paper, we introduce Load-Sensitive Continuously Variable Transmission used for knee joints of the two-legged robot. Among the joints of the two-legged robot, the variation of the torque necessary for the actuator is especially large in knee joint. In walking motion, two phases, swing phase and stance phase exist. In these two phases, the torque necessary for the knee joint actuators changes greatly. But reduction ratio of the actuators used for joints of the robot is generally constant. To solve the problem, we introduce a Load-Sensitive Continuously Variable Transmission in the knee joints, to adapt to the variation and then to achieve efficient walking motion.

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This study proposes a gait motion algorithm of six-legged robot using associative memory in order to walk in irregular field. This algorithm has a characteristic that enables the robot to recall next legs angle from present legs angle and touching the ground state sequentially. First, the algorithm is verified by ODE simulator. Secondly, the proposed algorithm is implemented to real machine. Finally, gait motion obtained by the algorithm is confirmed by experiments.

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In this paper a new approach to estimation of stability of mobile robots, such as multi-legged robots, is suggested. New methodology is based on an assumption that value of stability depends on the direction of input disturbance velocity, which, in turn, represents kinetic energy destabilizing the system.

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For the effective use of motor power, an appropriate gear ratio has to be selected according to the robot task and motion. Because a jumping robot, in particular, requires both high torque and high velocity properties through the motion, a varying gear ratio is necessary. Moreover, it has to be optimally designed and realized. In this paper, we design a jumping robot with a non-circular gear that changes the gear ratio through the motion for the higher jumping. Based on statics, the gear ratio is optimized and change of the gear ratio is obtained by a simulation-based design considering the robot dynamics. A jumping robot is prototyped and a non-circular gear is synthesized. From the experimental results, the energy loss of the experimental system is discussed.

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Power-to-weight ratio of actuators is extremely important for robots, particularly mobile robots. The combination of electric motor and speed reducer, which is the most common driving mechanism for robots, can utilize the motor in the area where its power output is high when the reduction ratio is appropriately designed relative to the load. However, in the case of applications in which the load significantly changes, the motor has to be operated in the area where its power output significantly drops. Therefore I have focused on the Radial Crank-type Continuously Variable Transmission (RC-CVT), which overcomes the limit of crank-type CVT. This paper proposes the load sensitive RC-CVT, which can sense the load and adjust the reduction ratio automatically. The Inverse and direct kinematics, statics, the design of load sensing device, and the test of the prototype are described in this paper. The application to a quadruped robot is also introduced.

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In recent years, people are going to be aging in Japan. Especially, in the case of care people, aging is very serious problem. For example, transfer care motion from a bed to a wheelchair does not have only burden on the caregivers, but also mental or corporeal burden on the Person Requiring Long-Term Care. So we develop a transfer machine which reduce the burden on the Person Requiring Long-Term Care. In this study, we clarify validity of the trial transfer machine. First, we explain the trial transfer machine using pneumatic actuators. Second, we analyze the transfer movement with both the transfer machine and human by an making use of electromyogram. Finally, we clarify effectiveness of the transfer movement by the transfer machine.

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A life support system using robotic physical agents for partial disabled people has been addressed. In this study, the life support system consists with three modules; the physical agent, the control interface and the life support reality server. This paper shows the control interface using the motion recognition system based on one hand gesture. Experimental results of a prototype application shows the validity of the proposed control interface.

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In recent years, researches and developments of Power Assist Devices are hot topics in the field of robotics. But, downsizing and insurance of safety of the system are difficult problem in order to realize the practical use. In this study, we focused on a meal task, and investigated suitable condition of an exoskeleton mechanism for the task by using analyses of maneuverability and manipulability of the proposed exoskeleton system. In this way, we showed the design strategy of the exoskeleton type Power Assist Devices to find out the suitable condition for the patients quantitatively.The performance of the proposed system and the validity of design strategy are verified through hardware experiments.

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Home oxygen therapy (HOT) is a medical treatment for patients suffering from severe lung diseases. Although walking outdoors is recommended for patients to maintain physical strength, patients always have to carry a portable oxygen supplier which is not sufficiently light weight for this purpose. Our ultimate goal is to develop a mobile robot to carry an oxygen tank and follow a patient in an urban outdoor environment. We have proposed a mobile robot with a tether interface to detect the relative position of the foregoing patient. In this paper, we improve mobile platform mechanisms with considering the usability. The leader following control algorithm is also improved and its effectiveness is demonstrated in an outdoor and indoor experiment.

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We are developing the autonomous mobile robot that assumes the application of the guide dog and the service dog. We designed a Lead-Robot "NWR002" that have three characteristics. 1) Maneuverable interface grip shape. 2) Small dead area of obstacle recognition sensors. 3) Reducing the several risks. In this paper, we describe about the concept and hardware design of NWR002.

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Users of an electrically powered wheelchair have several operation abilities and they change with time. We have proposed an electrically powered wheelchair with the operation assist system for a physically handicapped person, who cannot use a conventional electrically powered wheelchair. In this study, we propose a scheme for evaluation of operation abilities of users.

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The purpose of this research was to develop a control method for Robot Suit HAL, in order to provide walking support for hemiplegic patients. Support for the affected side of a patient's body was provided using motion data from the unaffected side. The HAL was used to sense angle and angular velocity data for the hip and knee joints on the unaffected side, and to generate motion in these joints on the affected side using feedback control based on the motion of the unaffected joints. Initial experiments were conducted with an able-bodied subject, to validate the proposed control method. The results revealed that the affected side could be made to perform effectively by generating motion based on that of the unaffected side.

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We have been developing the wearable muscle suit for direct and physical motion supports. The use of the McKibben artificial muscle has opened the way to the introduction of "muscle suits" - compact, lightweight, reliable, wearable "assist-bots" enabling manual worker to lift and carry weights. Since back pain is the most serious problem for manual worker, improvement of the back support muscle suit, operational system for practical use and interface suitable for the site under the feasibility study is shown in this paper. Also we investigate the ease of twisting of the body in the state where the muscle suit was worn and the effects of the muscle suit for lifting tasks.

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In order to assist human motion, we have been developing a compact and lightweight "Muscle Suit" which uses reliable McKibben type artificial muscles. The Muscle Suit physically supports the physical load of the wearer, and has high versatility and conveyance. The evaluation of effectiveness will become a key point on the development of the Muscle Suit. In this study, we used EMG that is used widely, in addition, used near-infrared spectroscopy (MRS) to indirectly measure the serum oxygenated hemoglobin and deoxygenated hemoglobin concentration of wearer's regional muscle, and attempted to evaluate the degree of fatigue.

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In this paper, we propose the upper limb power assistant device of using rubber-less artificial muscle. This power assist device is actuated by the rubber-less artificial muscle. The output characteristic of the rubber-less artificial muscle is similar to a biological muscle. We confirmed the output characteristic of the power assist device through simulation. And we discussed the power assist device with a high affinity for human.

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Previously, the authors have proposed "Wearable Third Arm": robotic manipulator which is to be put on by a human user and functions as an additional arm. Currently, they are studying on its control device using head inclination of the user as the input signal. The present paper newly introduces two types of input-output characteristics for the device. One is of a nonlinear time invariant gain property. The other is to change its instantaneous gain corresponding to the rate of the input signal. Then, results of simulation experiments are described. Consequently, the effectiveness and the features of the present two schemes are shown being compared to a conventional scheme of a constant gain.

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This paper describes the development of a fluid powered Motion Socks aimed to prevent deep vein thrombosis (DVT). In general, actuators have a characteristic that the more degree of freedom they have, the lager they are. Also, slippage between a body and wearable devices is an issue as well. In order to solve these problems, it is suggested the device called curved tube actuator for creating flexure motion of ankles using an actuator capable of generating force vertically to a body. The creating flexion motions of an ankle using this actuator were showed through experiment showing the effectiveness of the actuator regarding support of ankle motion.

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Recently in Japan, low back pain has become a serious problem. As a cause of low back pain is considered as a heavy weight or unnatural posture. So various studies that reduce the burden of the waist have been carried out. In this study, we develop the waist power assist wear using pneumatic rubber muscle. It is wearable device which consists of Mckibben type pneumatic rubber muscle and metal frame. And it assists extension behavior. We are measured EMG to ascertain the effectiveness of the device. As a result, the decrease in EMG could be confirmed, and the effectiveness of the device has been shown.

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The purpose of this study is to develop a lower limb power assist wear. This wear can generate an extension torque of a knee. This wear can be used to assist keeping a standing posture and going up and down stairs. In this paper, the structure of assist wear is described, and then the effect of this assist wear is confirmed from EMG.

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This paper proposes an active air mattress that improves utility of an cxoskeleton. The utility of the wearable assistive device is comprehensively judged by several items such as easiness to wear, body holding, pressure distribution and blood flow in holding area, humidity of forearm skin, and so on. This paper focuses on easiness to attach the exoskeleton on a user finger and stability of finger holding. Through some experiments, we confirm that the active air mattress improves easiness to wear by comparing with a conventional fasten device, a magic tape, and that stability of finger holding is as same level as the conventional one.

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This paper reports improvement in affinity of a support system with a new active air mattress from viewpoint of a high tolerance for user's body size. The active air mat allows users, whose forearm girth is from 198mm to 262mm, to wear the support system. The range covers 89% of Japanese population. The rigidity of the air mat's holding is evaluated by comparing accelerations and angular velocity of a wearer and of the exoskeleton when he swings his forearm with the exoskeleton. Besides, it is confirmed that blood flow around the forearm is secured by inflating and deflating air chambers of the air mat sequentially in the same direction of venous flow.

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Human locomotion control is atypical issue of multi-body system control that may be specific for periodic and stable motion patterns of locomotion. In this study, we investigated the human locomotion by mode analyses using singular value decomposition. From motion-captured data of human locomotion, we extracted common basic movements and residual modes, and analyzed kinematical structures. The results show that there are basic movements whose proportion of variance is significant and those are common to all the test subjects. And the residual modes involve personal peculiarity or symptoms of motor dysfunction in locomotion. We can note that utilizing the results, it may be expected to identify the personal and run diagnostic check systems for applications.

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This paper deals with a small wireless bio-electrode for man-machine interfaces. The authors have proposed the "Universal-interface" as a kind of man-machine interface with high flexibility. The authors developed small wireless bio-electrode "VAMPIRE-BAT" for this interface. It can vary its own analog constants such as gain or cut-off frequency of filter during measurement.

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While there have been many works on BMI and medical diagnosis by using brain signal, it is really hard to extract pure brain signals in noisy environment. Focusing on auditory related brain signal, we challenges to detect auditory evoked potential in real time by utilizing the newly developed EEG measurement system. The key idea is to utilize a master signal whose frequency is determined based on preliminary calibration tests. We evaluated the existence of auditory evoked potential by taking the correlation coefficient between the master signal and the auditory evoked potential of measured signal, and confirmed the effectiveness of the approach.

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The objective of this study is the realization of recognition of human body movement using IMU (Inertial Measurement Unit). This paper shows segmentation and the recognition results of the movement of the right arm during Japanese drum performance to confirm the segmentation and recognition possibilities. In past studies the real-time recognition of human body movement using joint angles acquired by motion capture as been realized. The program of segmentation for joint angles is appropriately modified for angular velocity. And to adjust the parameter settings in order to match the segmentation results in manual segmentation results. The similar movement patterns are classified into each model. Recognition is performed using these models.

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Microscopic structures of human motions including standing, swaying, and stepping are visualized in phase portraits based on the COM-ZMP model. In order to observe behaviors in wider area of the state space experimental protocols are devised with a reference to the portraits in theory. Some results with qualitative discussions are presented.

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Today, Virtual Reality (VR) technology has been applied in various fields, and the influences for human induced by VR contents have been studied. VR contents mainly use the visual stimulation, and the influence induced by the vision stimulus has been evaluated by center of gravity or a questionnaire survey. Meanwhile, in our laboratory focused on the postural sway induced by visual stimulation and has experimented using the numerical modeling technique of input stimulus and postural sway. As a result, it was confirmed that the model parameters have a certain tendency. In this research, long term experiments have been conducted to check the validity of the proposed analysis method. In addition, the possibility of the application for time series modeling method to the postural sway analysis is also considered.

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In this paper, based on our proposed admittance control for holding up a load with EMG signal, a negative admittance control is developed for holding down the load for power assist. First, it is confirmed by the experiments that the main muscle used for elbow lifting is biceps brachii, and shoulder lifting is deltoid clavicular part. Then, the experiments for elbow and shoulder joint motion support are implemented, and the results show the effectiveness for holding up with admittance control and for holding down for proposed negative admittance control.

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In this paper, we originally developedan generalized admittance control approach for human motion support using minimal EMG signals. Generalized-admittance is an extension of the traditional admittance control, in this report, it was confirmed by the experiment that the main muscle used for lifting is biceps brachii. Experimental results verified the effectiveness of the proposed approaches.

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In this paper, a 20-DOF miniature humanoid MH-2 is developed to achieve rich remote communication. MH-2 has dual 7-DOF, a 3-DOF head and a 3-DOF body. An operator can communicate with remote people through the robot. In other words, the robot acts as an avatar of the operator. It provides sophisticated gestures because of multi degrees of freedom. Fundamental experiments show its feasibilities.

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Humans perform movements with adjusting their body impedance to environmental impedance. A Lack of such adjustment ability decreases human performance for optimal movement control to adapt changing environments and contact events. The purpose of this study is to develop an evaluation method for human impedance adjustment ability on lower limbs. In this paper, as the second report, we proposed an estimation method of impedance parameter, especially on stiffness, during pedaling exercise. An experiment system for measuring the impedance was developed. We evaluated the changes in endpoint trajectories during the pedaling exercise under a discontinuous velocity-dependent force field in order to predict an actual trajectory correctly.

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Evaluation of physical driver fatigue while driving is important issue to realize safe and comfortable driving. Therefore, studies about fatigue on sitting of the driver. However, they are often focused on material of sheat. Therefore we focused on seat of car with the lumber support in this study. At first we evaluated physical fatigue of driver by using a driving simulator. We use the evaluation technique based on finger photoplethysmogram of biological information. It has been found that the lumber support reduce the driver fatigue. As a result, the effectiveness of the lumbar support has been confirmed.

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This paper presents the multi mode model of the human driving behavior based on the hybrid system. We conducted the experiment to collect driving profiles in order to create the driver behavior model. The driving profiles were collected by using the electric vehicle namely COMS. we have to construct models which considered regenerative brake effectiveness because the COMS include the regenerative brake system as standard equipment. The driver behavior model identifying problem was solved by using the data clustering technique and the linear approximation method. The autonomous braking system experiments were performed with the driver behavior model. As the results, it has been found that the actual driving behavior and the autonomous driving behavior agree well with each other.

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