In general, a work of disabled people in a wheel chair is a deskwork using computer at an office or a production line work in a wheelchair in a factory. Because they are forced to be in a wheelchair, their jobs that they can get are limited. If they can stand and move their arms freely, they will have more choices of their works. This research is to develop a new robot for people with dysfunctions of lower extremities to support their working in the upright position and contribute to expand range of their works. To support their working, keeping the upright posture and giving a space in front of users that they can move their arms freely is important. In this paper, the need of this robot and its necessary specifications are discussed.

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Along with the steadily rising elderly population in Japan, the number of aged persons with difficulties in walking is increasing. These patients undergo rehabilitation in hospitals which impose a constant and heavy burden upon the health care personnel who must assist them. For patients to rehabilitate by themselves, a walking support machine is needed that can unload their body weight and prevent them from falling down. This paper deals with safety devices (to unload patient's body weight and prevent falling down) used in a walking support machine. These devices consist of only mechanical components without actuators. The usefulness of these devices is experimentally examined.

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A dorsal flexion controlled lower limb orthosis for paraplegia is developed and evaluated. Dorsal flexion of ankle joint in swing phase is useful to get clearance between foot sole and floor, for easily carrying a lower limb from aft to fore. To realize this, MR brake is installed in the ankle joint of orthosis which is fan shaped and made of aluminum alloy to move 70 degrees from dorsal to plantar flexion. The MR brake filled with magneto-rheological fluid has an outer loop of MR fluid and flow viscosity is quickly changed by moving permanent magnet block. MR brake is active during the swing phase detected by the foot sole switches. The effect of the MR brake to hold the dorsal flexion in swing phase is proved experimentally by a polio patient of drop-foot on level walking.

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Many hemiplegias use Ankle-foot orthosis to prevent falling when they walk. In order to support natural walking of hemiplegias, we develop a new ankle foot orthosis by using self-powered semi-active damper. A DC motor and step-up chopper circuit is used to regenerate energy. Theoretical analysis for electrical circuit and energy generation and gait experiment using this ankle foot orthosis are carried out. From the experimental results, it can be seen that this system can generate 80 percent of the consumed electric power.

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This Paper describes on small rehabiritation equipment. If hands and feet are paralyzed by the apoplexy, and this paralysis is untreated, the joint is transformed, and contracted. After the attack, immediately rehabilitation is important to recover hands and feet who can actually use. It's just conceivable that physical therapist have a shortage along with a low birthrate and an aging population, because there are a lot of apoplexies in the elderly person. For this reason, the autonomous rehabilitation equipment is necessary. Then, in this report we adopt the bellows mechanism to respond to the movement of the finger flexibly, In addition, the method to drive the bellows mechanism by hydraulic cylinder was designed. We actually produced this autonomous rehabilitation equipment, and effectiveness of this mechanism was experimentally confirmed.

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This Paper describes research on pet robot of biped locomotion with short legs. Today, pet robots are increasing to be used in welfare field. Pet robots used in welfare field are requested to give elderly people to familiarity and enjoyment, comfort. One of objects that people feel familiarity and enjoyment, comfort is deformed animal of biped locomotion with short legs, In this study we searched for of elderly people liking which of the three pictures of deformed animal with the different length of legs, and liking either one of the two workings. This paper reports availability of pet robot of biped locomotion with short legs and consideration of working of this pet robot for prevention of dementia in elderly people.

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The Shape memory alloy actuator has large starting torque, so it does not need a reduction gears and cam mechanism etc. Moreover, it has greatly high power weight ratio compared with other actuators. Therefore, if the shape memory alloy is adopted for the actuator of rehabilitation equipment, the total system of this equipment is smaller and lighter than conventional system. However, the servo system of shape memory alloy needs a heat control with phase transformation, so the control of shape memory alloy is more complex than other actuator. In this research, we consider various problems of application of the shape memory alloy actuator for rehabilitation equipment of hands and fingers, and we actually examine it experimentally.

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The final purpose of this research is to develop a walk training machine for people who have problems with their lower limbs, for example bedridden people who suffer from a weakened motor function. Generally a walk training machine is setting type, which has a problem such as the tiredness of the patients because of the static condition in a long time training. For the reason we performed development of a moving type walk training machine that can move with motor-driven wheels. The patients can perform walk training outdoors with it and can be released from monotonous training. The other peculiarity of our walk training machine is because it is using a linkage mechanism to move the legs of the patient. We adopted 4-bar linkages that can be installed apart the patient' legs and relieve actuators' weight. To evaluate our walk training machine, we used three ways; Surface-Electromyogram (s-EMG), Physiological Cost Index (PCI) and motion capture system (vicon).

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We have developed a manipulator for supporting human lower limb rehabilitation that enables isokinetic muscular contraction to both knee and hip joints simultaneously. This time, we estimate muscular tensions in thigh and pelvis area of a healthy person during exercise by the manipulator to realize a biofeedback treatment without using electromyogram (EMG). The muscular tension estimate is made by employing muscular fatigue minimization methods. As a result of experiments and analysis, fairly good coincideence in the wave form is confirmed between the muscle action potential and the estimated muscular tensions.

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Gait transition is a transient movement between upright posture and steady state gait. The purpose of this study is to introduce a gait transition model including a musculo skeletal model, neuronal model, proprioceptive model and higher center. Gait transition motion was divided into three phases of standing, transition, and walking. Neuronal parameters in each phase was decided by genetic algorithms. At first, the standing and walking parameters were searched, then, the transition parameters were also searched by specific objective function. The simulation result showed that the introduced proprioceptive model was important to keep upright posture, also, the impulse output from higher center was indispensable for a transition of motion.

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Calculation and programming algorithms of real-time estimation of three-dimensional walk trajectory are discussed. A body-mounted sensor which is composed of one 3D accelerometer, one 3D gyroscope and one 3D geomagnetic sensor is attached on tiptoe of right foot. The 3D trajectory is derived from double integration of acceleration and integration error of the acceleration is effectively cancelled by considering continuity of the velocity of the foot at the end of the swing phase. Data acquisition followed by trajectory calculation and real time expression of the walk trajectory is executed on real-time Linux operating system. Presentation of the walk trajectory during the swing phase uses gnuplot data plotting utility and is completed during the following stance phase. The experimental results of the level walk showed that the walk trajectory was displayed in real time and took 20 msec from the detection of the stance phase to the end of the trajectory calculation.

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We have developed new type of walking orthosis for paraplegics named "HALO". The HALO orthosis has a linking mechanism that connect both ankle joints with a medial single hip joint. This orthosis allows users to keep both feet always parallel to the floor while walking, and assists the swinging of the leg when the contralateral ankle is flexed dorsally by loading. To evaluates this orthosis, we performed gait analysis useing 3-dimensional motion analysis system and force platforms and compared with previous type of orthosis for paraplegics. The results of analysis showed that HALO orthosis gives stability in walking and utilise the dorsiflexion moment of ankle to assist the swing of the contralateral leg. However, there is the usage of the better dorsiflexion moment, and further improvement has been left.

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This paper describes a newly developed hip disarticulation prosthesis of which a rotational center of a hip joint was made closer to an anatomical position. The new hip joint was proposed and designed, and a prototype of the hip joint was fabricated. The hip joint was integrated with a socket of a hip disarticulation prosthesis, and a new hip disarticulation prosthesis (nHDP) was made. Choosing an appropriate knee joint and foot for the nHDP through the trial and error, a hip amputee could walk using the nHDP. In order to evaluate the nHDP, analyses of walking motion were performed for one subject. The result showed gait using nHDP had less unsymmetrical motion of lower limb compared with gait using a existing hip disarticulation prosthesis which was used by the subject in his daily life. It was shown that the nHDP was effective for changing gait of hip disarticulation amputee better.

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This paper presents a new ankle-foot orthosis (AFO) for hemiplegic patients. The proposed AFO has a pneumatic passive element, with the rotational axis at an ankle joint, arid it can adjust the ankle-joint constraint force according to the subject's gait phase. We confirm that the adjustment of pneumatic pressure in the proposed pneumatic passive element is efficient to realize the performances of some conventional AFOs.

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A visual digital recorder system (DVR) is widely used to visualize and analyze the dynamic image of moving body. The instrumentation system of the DVR is applied to study and analyze two-dimensional moving images of the walking human body. However, studies of dynamic behaviors on human body are very little. In this paper, dynamic behaviors of human body segments like location and velocity of walking human bodies are visualized and measured using DVR. Fluctuation characteristics of frequency f, power spectrum density PSD and coherence C of five young and old persons were quantitatively analyzed and evaluated for four segments of each person. Lastly, it was concluded that fluctuation performances of the moving human body were largely influenced by person age.

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Three people participated in the experiment, an elderly female (she could not stand up easily), healthy elderly and young males. Their standing-up motion from a chair was observed by using infrared cameras and force plates. The young and elderly males stood up rapidly and dynamically without over-bending whereas the elderly female stood up slowly and statically with over-bending due to decline of muscle strength. In addition, the standing-up motion for the elderly female was unstable in comparison with that for other two subjects. As factors causing the instability of standing-up motion, the position of the body and knee stability were focused. Bending the body forward during standing-up destabilized the motion. The knee sway during standing-up for the elderly female was greater than that for other two subjects. The stability of standing-up motion for the elderly female was well improved by wearing knee supporters since the knees became stabilized.

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This paper describes a design of a wearable sensor system to measure the ground reaction forces during human walking. First, the basic concept is discussed. Second, on the basis of the concept, the sensor system is proposed. Third, the sensor system is developed. Finally, the usefulness of the sensor system is examined from its experimental results.

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It is widely thought that visual sense, somatesthesia and vestibular are attributed mainly to control the human movement. It's very difficult to measure the attributes of them on posture control. It's reason why there are few evaluation methods of posture control capability based on characteristic of those sensoriums. A mathematical model for human posture control system having visual sense, somatesthesia and vestibular model was proposed in this study, and this paper describes a method of estimating human attitude stability quantitatively by identifying the parameters of somatesthesia model in this human model. The proposed simulation model well represented the characteristics of tracking task collected from the experiment. Sensitivity of the model parameters could explain the difference before and after exercise. The validity of this evaluation method is examined.

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Generally, Muscular strength of knee extension, Walking speed, and Step length are recognized as important index for evaluation of walking ability. As measuring the above index, however, we need to have not only much technical knowledge to deal with equipment but also much time to process of the obtained data. It is not in the situation that we can evaluate the walking ability easily. In this paper, we report that a simple method by using of an accelerometer is useful to estimate the walking ability.

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This paper describes a novel method to measure spontaneous body sway in static upright stance by using a CCD video camera system. Three markers were put on subjects' back and legs, and three cameras were employed to record the motion of makers, respectively. Body sway in coronal direction is optimal for stability evaluation. During a period of 30 seconds of recording time, averaged angular velocity (TSSr) of the body sway is calculated, and was used as an index for the stability evaluation. To minimize ageing and physique influences on body sway, an empirical model was established to calculate the standard value (TSSeo) of body sway in different age, weight and height (all in eye-open). An investigation on a 51 elderly females group proved that the ratio of TSSeo/TSSr is quite correlated with falls happening frequency. Further more, a PID control model was as used for balance keeping study. The results suggest valuable of this model for stability evaluation.

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The gait of elderly amputees is less stable than healthy elders due to his/her amputation. We developed the new prosthetic foot to increase the stability of the prosthetic gait pattern, especially to reduce the lateral instability. In this paper the evaluation with three parameters about the lateral instability of the gait is described. One is the lateral displacement of Center of Gravity, it's traditional theorem, and the other are Lyapnov Exponents of COG lateral displacement pattern, it's means of reproductive of the displacement pattern, and External Fall Moment at prosthetic side stance. In most cases these parameters revealed the reasonable advantage of the the new prosthetic foot, however the elder amputees prosthetic gait tended to be irregular. It might be necessary to evaluate by multiple parameters including subjective evaluation and measuring with the prosthetist's eye.

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A new insole for a shoes, including water in the sole called the water insole, was developed, which joined a power of walk and a period of a walk to the shock absorption of a heel and a tiptoe part in walking. A flow of water in this insole is controlled by the positions and sizes of some dams and some orifices in the insole. The foot pressures are measured for some insole and the effect of shock absorption for the new insole is verified. In addition, a massage effect to the arch of a foot part was subsidiarily provided.

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An immediate start of artificial ventilation by inserting a tracheal tube through mouth or nose can improve a survival rate at the emergency situations suffering from apnea. In this study, we report a novel multipurpose expanding medical tube which can be used as a tracheal tube which maintains the shape for the airway. We pursued the possible clinical application of the expanding tube to widen narrowed airway by inflating it after inserting in a thinned condition utilizing its flexible transforming capability. In practice, in the current study, we made a prototype model of the expanding tube made of nylon, and studied the structural transformation by numerical simulation. Additionally, we created a model of the airway structure from mouth to trachea, and evaluated the feasibility of the test expanding tube as a tracheal tube by applying to that upper airway model.

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This paper describes the effectiveness of supporting chair which is known as one type of welfare device. Their effectiveness was clarified by doing the following evaluations. Firstly, there was a subjective investigation for using senior persons. This was done for the purpose of checking their feeling in the time that they used the supporting chairs. And another was to measure the load on their lower limbs (ankles, knees, hips) when they stood up from them. This was calculated by modeling the body as the rigid one. From the results of this study, it was clear that supporting chairs decrease the load on lower limbs during standing-up motion very well. And the study also found that supporting chair has problems during their support action.

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The purpose of this study is to establish a new effective process of developing assistive products. In this process, the psychological effects caused by using an assistive product are carefully examined before forming the concept of a new assistive product. It is assumed that the emotional conflicts which the older persons could show even after they chose the appropriate assistive devices suggest their needs. To clarify and analyze their psychological situation, the qualitative research approach was employed. Using this approach, the psychological model of older persons which can explain their emotional conflicts was established. This development process is based on the model. In product design using the process, the complicated psychological situations are taken into account at the stage of conceptual design. Finally the example that a mobility aid is developed using the process is introduced.

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A planetary roller type speed reducer was developed for an electric wheel chair, in which the output speed is given by the rotational speed of the career. When estimating the required torque, the traction under an elastohydrodynamic condition was determined with a roller-on-disk type tester. As a result, the coefficient of traction in the linear region of the traction was adopted. The power performance of the planetary roller type speed reducer was determined with a test bench equipped with a real traction drive, where the variation in acceleration with torque was measured.

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A one hand drive wheelchair with power assist mechanism is developed in our research group. In this paper, the assist function for running slope is improved. The brake function and the power assist function of turn left and right after reverse prevention on slope, which are new assist functions, bring about the reduction of physical load and the progress of safety to the manipulator in running slope. The effectiveness of new assist functions is verified through experiments using a prototype.

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A small active seat suspension has been designed and manufactured for a one-seat electric vehicle. Our aim was to develop a vibration-isolation system for the driver's seat suspension using active control. However, the evaluation of ride comfort during the electric vehicle running has depended on subjective judgement by drivers. Thus, it is necessary to evaluate the correlation of subjective judgement with objective judgement according to physical values, i.e., vibrations. In this study, ride comfort ratings evaluated subjectively by the "Paired Comparison Method" were compared with the measured acceleration of the seat surface. In addition, The factor that influenced the subjective evaluation value was examined.

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A robotic wheelchair with inverse pendulum control has been proposed for a wheelchair-bound person to climb over a step without a helper's assistance. The robotic wheelchair raises its front wheels in front of a step, and maintains the inverse pendulum control. The human emotion of the rider during the inverse pendulum control has been discussed in this paper.

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Trial production of a prototype of stair-climbing powered wheelchair and an improved design under its proving test are presented in this paper. During the past few years, 2 prototypes have been developed for handicapped or elderly to move up and down along the stairs by customizing a commercially available powered wheelchair. After making reviews on these prototypes, new prototype 3^<rd> has been planed and produced with a particular emphasis on torque transmission mechanism from powered wheelchair to reduction gear and an automatic docking mechanism of wheelchair and hoist carrier plate.

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For helping attendants of handicapped people and senior citizens, a power assist system is added to an Omni-directional Wheelchair (OMW). With this addition it is possible to deal with heavy loads, but there is a problem of operability when the attendant wants to move OMW laterally or rotate around OMW's gravity center. For solving this problem fuzzy rules are applied to estimate the navigation direction for the force given by the attendant. A neuro-fuzzy system is used for the tuning of the membership functions of the fuzzy system according to each attendant's characteristics. Further, a second order lag controller which transforms the force given by the attendant into the velocity of OMW, is presented for achieving rider's comfort.

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Our research on development of welfare equipments was started around 1998. This report is concerned with welfare equipments, four kinds of powered moving devices for physically and mentally challenged children who can not move independently. Trials have shown that children with disabilities can maneuver the powered moving device easily and safely. As the results, the children can be move active and gain a sence of independence and play.

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We propose the rising detection reporting device which can be installed in the middle-small facilities and ordinary houses. This device combines a mat sensor which detects rising and a power line communication (PLC) device as a reporting system. This device does not need any additional construction for installation as long as the facility equips electric power supply 100V for ordinary business. At first, the mat sensor in the system detects rising of a elderly person or lying down to the bed. The PLC system sends on/off signal and reports to nurses and caring people in the management room. Since the main objective of the PLC system is exact detection and transmission of the mat-sensor on/off signal, high-speed network is not necessary. It is required that the system should be robust to noises of household electrical appliances. We used the multi-career method as a transmission method in which we located 2 lines of tone frequency (115KHz and 132 KHz) for the power line transmission in the device. The effectiveness of the proposed device has been confirmed by the field experiments in welfare facilities for the elderly people.

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