There are so many sounds to be recognized in order to lead daily life without any difficulties. For the hearing impaireds it is necessary to be able to get information by other means. In this study, alarm sounds, such as sirens of emergency vehicles were studied for a classification of alarm sounds by applying FFT, STFT, ANN, and combinations of these. However, these classification methods were not enough to classify some alarm sounds and to expand applications to other sounds of daily life. So, the computational auditory scene analysis (CASA) was applied and studied for the classification of alarm sounds.

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A Passive Exercise Training Equipment has been developed, by which persons with the gonalgia can reasonably perform exercise training in the leg and can obtain metabolic promotion. The equipment has the saddle and the foot plate, which is controlled by using 4 servo motors. The saddle is declined to the each geniculum direction, and the foot plate is elevated up-and-down in order to keep the angle of the user's knee joint. By conducting a laboratory experiment using Near Infrared Spectroscopy, it was indicated that the muscle metabolism (muscle oxygenation) amount of the femoral region was promoted about two times of that of resting period. The average of the face pain scale of the gonalgia person was more than 17 points (assessments are 20 points top grades). It was suggested that the movement velocity and the rate of the body weight could induce the pain of the knee joint.

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In this research, we propose the teaching materials with personal computer and several input devices to improve communication ability of handicapped children. Furthermore, we discuss on the application of a wireless toy for the same purpose.

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In this paper, the authors report on development of a 3-DOF function training machine system for upper limbs and some software for clinical application.

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We are applying a mechatronics device to assess and assist the rehabilitation of the palsy arm. The rehabilitation device is developed for assisting the physical and occupational treatment of the upper arm for the patient with cervical spinal cord injury. The system consists of a personal computer and a joystick-type controller. A triaxial load cell is installed in the controller to measure the force exerted. With this system, we propose isometric training of the arm with a biofeedback of visual effects as in video games. The trainee is to adjust the force of the arm to follow the moving target along the trajectory displayed on the screen. In this report, we discuss the effect of the grip on the training performance. Our grip holds subject's palsy hand at the palm and meditates the response of the arm to the controller. Samples were taken from able-bodied subjects, which were arranged as temporally handicapped by fixing the joints in the digits. The error of fallowing the target on the screen is compared between the joystick shapes.

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There are some researches to develop an EMG hand for the arm amputees. In the clinical or practical field, there have been no experiences compiled on prescription, training, evaluation and fabrication of the use of the EMG hand. As a result, there are no steady evaluation whether the EMG hand is useful or not for the amputees. The authors started to try the commercially available EMG hand for mainly unilateral forearm amputees to have an experience and evaluation. The paper reports about the result of 25 trials.

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Architects usually use the standard architectural guideline manual, provided by government when they build facilities in consideration of the disabled and aged. In the architectural guideline manual, it is stated that gradient of any ramp or slope has to be 1 : 12 by ratio or less and wheelchair users can't negotiate any elevated surfaces with exceeding the height of 2cm and so on. There are very few housing guideline manual for the disabled available because it is difficult to cater to all disabled individuals' wheelchair specification and mobility. We strive to create personalized architectural guideline manuals for disabled individual.

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Performance of step-climbing is an important function for wheelchairs. Authors have proposed the dynamical model of step-climbing mechanism, and derived the equation with the force that enables the front wheels to be lifted on a step. In addition, authors manufactured a multi-function wheelchair equipped with power unit, step-climbing mechanism and chair-elevating mechanism. Comparisons between the measured forces for step-climbing and calculated results are in reasonable agreement with the trend.

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When trying to improve the lifestyle of people with disability a conflict occurs because of the different degrees of physical impairment. We evaluated new types of barrier free curb cuts (useable for both wheelchair users and visually impaired persons) at a crosswalk. First we focused on the shape of curb cuts. We compared the new curb cuts with the conventional curb cuts by evaluating impulse, energy and electromyogram (EMG) activity. Next we focused on material of curb cuts. We compared the new curb cut with the conventional curb cut by evaluating impact when wheelchair runs over the curb cuts. Consequently we found advantages with the new types of curb cuts.

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The physically handicapped with the traditional wheelchair is difficult to overcome the bump, and the care personal, too. Furthermore, by the fixed seat of wheelchair, it is hard to take things of height position and it becomes a burden. In this paper, the attitude control mechanism which can adjust the height by using 4 flexible axes, is developed for the wheelchairs. Further, 4 flexible axes were controlled according to the angle of seat by using an angle sensor, and the seat level always was kept. The control mechanism can prevent turnover accident in the wheelchair and can correspond to the load surface.

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It has been required recently to correspond to the problems such as diversity of the physical disability and aging of disabled persons. Hence, the improvement of performance for welfare equipments such as wheelchairs is required by such social background. There will be three problems for the operation of conventional wheelchairs : to pass on the place with level difference, to stretch the body to take the thing of higher place because the wheelchair seat is fixed at low position, to move the user of a wheelchair to another place such as the bed. To solve these problems, the authors have developed a new type of wheelchairs with an adjustable seat; four motor-driven vertical shafts to adjust the height are attached to the traditional wheelchair. It is called angel-mam. This paper introduces outline of the wheelchair and the control mechanism of height adjustment using PIC (Peripheral Interface Controller) which is a kind of micro controller. In addition to them, the biomechanical analysis for a helper, who lifts up a wheelchair user to the bed, because such works will give the most severe physical burden.

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One factor which makes it difficult to operate a wheelchair when crossing slope is the behavior of the wheelchair and the user. It is important to clarify the influence that behavior of the wheelchair exerts on the user. An analytical model of the wheelchair which considers the casters was made. The calculation results and meandering over the slope by an analytical model were compared and good agreement was obtained. Frictional properties used when analyzing it used the method of the design in this laboratory. We conclude that instructions of the database for wheelchair manufacture are easy to use following the results of our research.

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In this study, we evaluated the influences of ascending hill on operating the wheelchair quantitatively. It was found that the slower the wheelchair ascends hills, the more momentum per 1m traveling needed. It seems that the weaker the wheelchair user the more momentum he/she must spend to negotiate the hills. It also became clear that whether a wheelchair user is able to negotiate a hill would depend on how long the recovery phase time could be made in maneuvering the wheelchair.

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It is difficult to drive a wheelchair through snow, because of swamping caster tire. In this study, we developed a prototype of a motorized crawler with a drive assist unit that can be installed in a standard manual wheelchair. The user can operate the crawler's steering and pitching with a handlebar, therefore the unit has a high performance on snow-covered roads.

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With advance of an aging society, the person who is physically handicapped has his respective needs about mobility assist with his living conditions. However, as the common needs of them, a new wheelchair that can turn in a small space and has a different image from the conventional one is required. In this paper, to respond these needs, a new compact and low priced omni-directional electric wheelchair is proposed. Moreover, operating an electric wheelchair indoors in confined spaces requires considerable skill. This paper also presents an obstacle avoiding support system for an electric wheelchair, using reinforcement learning. The system adds virtual repulsion from the obstacles to manual input from the user. The virtual repulsion is tuned corresponding to each unique environment or user condition. Then, the size of the virtual repulsions are determined by the reinforcement learning controller. The newly proposed scheme is numerically evaluated on a simulation example.

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In the present research, we measured the acceleration when subject drove a wheelchair on the two patterns of Textured Block (guidance panel for visually impaired people, warning panel for visually impaired people) and on drums where a bar was attached to two of the drums to make an uneven surface which the Wheelchair wheels ran over. And we made our evaluation of riding comfort based on a wheelchair vibration and human body vibration and exposure boundaries. According to the result, it became clear that the vibration when driving on the guidance panel is uncomfortable. Exposure boundaries were about 25minutes. And when compared with guidance panel with drum, the result on evaluation based on a wheelchair vibration says that guidance panel is more uncomfortable, on the other hand the result on evaluation based on human body vibration says that warning panel is more uncomfortable.

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To start with the investigation on the mechanical response of the human skin, this paper takes into a consideration of the view point of study where mechanical properties and chemical aspects of the skin should be examined. In particular, chemical aspect, for example, whether the factor is correlated with a chemical reaction or a diffusion of the chemical species in the skin, should be important when we clarified a reason of mechanical properties with time-dependency.

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Handling of conventional input (or interface) devices to the IT systems, such as keyboards and mice, are not so easy for the aged and handicapped people, and as a result, it build high psychological barriers between the IT systems and them. The present study aims to establish a guideline for designing software keyboards on touch screens, which seems much easier to handle than other input devices. As a starter, we examined the dependency on the age and sex of the users (Aging Effect and Sexual Difference) on the dynamical properties of pointing movements on a touch screen. The major results are as follows : 1. Fitts' law (MT=αlog_2D/S+β) did not hold too much when the subjects repeated pointing movements between two targets that are close to each other on a touch screen. Rather, the movement time (MT) increased linearly to the ratio of the index of difficulty (ID) between targets to target size (S)(i. e., MT=αD/S+β). 2. The coefficient α took almost the same value in the older and younger groups of subjects. On the other hand, the intercept β was significantly different between two groups. 3. The coefficient α took larger values for female subjects than for male subjects. It was also observed that the movement time (MT) was almost the same value (or shorter) for female subjects when the index of difficulty (D/S) was small, while it was shorter for male subjects when the index of difficulty was large.

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Adequately understanding individual's physical characteristic and reflecting it in the wheelchair adaptation are important to achieve efficient wheelchair propulsion and to decrease physical loads. In this paper, we applied the analysis of the mechanism of robot manipulators in our evaluation of the manipulation ability of the upper limb. The effect of individual's muscular power characteristics on the easiness of hand force manipulation is expressed in the six-dimensional ellipsoid. The relationship between handrim operation and manipulation ability of the upper limb was clarified by considering spatial change of the six-dimensional ellipsoid in the wheelchair propulsion. The results of this paper add technological proof and quantitative index based on individual's manipulation ability of the upper limb to the conventional experiential wheelchair adaptation.

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At present, manual wheelchair users are at high risk for repetitive strain injuries (RSI). And as high as 50% of manual wheelchair users have upper extremity pain. One of the factors is recovery motion in the driving wheelchair. Then, in the present research, we focused our attention on propulsive stroke, and we clarified the difference in upper extremity electromyogram (EMG) activity between the push phase and recovery phase. And we compared the 4 general patterns of propulsive stroke of manual wheelchair users with analysis of the upper extremity motion and EMG activity. Consequently, muscular activity of the Biceps, Pectoralis major and Deltoid anterior was mainly performed at the push phase, and muscular activity of the Deltoid middle and Deltoid posterior was mainly performed at the recovery phase in the driving wheelchair. Moreover, as a result of comparing upper extremity EMG activity with the 4 patterns of propulsive stroke which differ in recovery motion, we found advantages with Arcing (ARC) propulsive stroke which uses less upper extremity motion at the recovery phase.

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For reducing traffic accidents by aged drivers, researches on active and passive safety technologies and driver characteristics have been carried out. However, several research achievements are little effective for aged drivers since the characteristics of aged drivers are distinguished from normal drivers and difficult to analyze. In order to clarify the distinguished factor of aged drivers, this report is based on the assumption that aged driver characteristics are related to both their life style and physical characteristics. The driver characteristics, the life style, the physical characteristics are investigated from several questionnaire surveys followed by experiments using driving simulator, and actual driving test. The evaluation method of aged drivers' driving performance is proposed based on life style and physical characteristics, and this method provides useful suggestions for understanding the aged drivers' driving characteristics.

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Tactile ground surface indicators installed on sidewalks help blinds walk safely. Blinds distinguish the indicators by stepping its convexities and follow them. However, these indicators sometimes cause people who do not use them while walking to stumble. This study examined the effects of these indicators, by comparing kinematical variables, and kinetical variables of the path with and without indicators. The results suggest that walking on the indicators cause inappropriate movement of lower extremities such as increasing of minimum toe heights during the mid-swing phase. This inappropriate movement of lower extremities has caused by either increasing of peak hip flex moments, or increasing of peak hip heights. This study also suggested that temporal differences of leg length while walking on the indicators are one of the reasons which causes the above-mentioned inappropriate movements of lower extremities. Therefore, we designed new implanted indicators to offset the differences of leg length while walking on the path with indicators installed, and found that newly designed implanted indicators were effective enough to reduce the inappropriate movements while walking on the path with indicators installed.

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It is said that the motions of top athletes and experts of Bushido have in common in the sense of using hip joints. In this paper, a trunk-twistless walking, named 'namiashi' is measured and investigated. It is estimated that external rotational moment of hip joints is effectively used for compensation of the twisting moment of the body. We identifed that the multiple-peak pattern of the acceleration is one of the characteristics of this walking motion. It can be considered that dispersing acceleration by using the external rotational moment leads to reducing muscle fatigue.

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We propose the mechanism of a new biped humanoid robot capable of being used as a hardware simulator of human motion. The humanoid robot consists of a 3-DOF in each ankle, 1 DOF in each knee, 3 DOF in each hip and 2 DOF in the waist. Also, a knee stretch walking pattern generation is described in this paper. The singularity of the swing leg that can exist in a single support phase will be avoided by the motion of the waist. Through walking experiments, the effectiveness of the biped robot mechanism and stretch walking pattern is confirmed.

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The purpose of this research is to establish a three-dimensional biped walking simulator, which models the feature of neural and muscle properties of human, to apply for stair-walking. The walking stability and the stair height were improved simultaneously by including the height of stair in one of the search parameters foe genetic algorithms. This simulator could be adapted for walking on the higher level stair than our previous study. In order to adapt the model for further higher level stair, it will be required to include distance to the stair and height of the stair that are obtained from vision information.

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In this paper, the role of the human being is investigated. The change of the toe pressure is measured at walk by the existence of a toe using a toe pressure measurement system. In order to investigate the change of the whole walking, the affection of a walk posture using a 3D motion capture system by the existence of a toe is also measured. Furthermore, the change of the amount of energy consumption at walk by the existence of a toe is measured by a spirometry system. At last, we investigate the roles of the toe, such as, the effectivity of the 1st and 2nd finger, and the stabilization of the posture, by the synthesis of these results.

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We have proposed estimation method of vertical reaction force and ankle joint moment by using a plantar pressure sensors in the previous paper. In order to use this system more efficiently, this system should be applicable for many persons who have different foot-length. In this paper, we carried out experimental study to examine accuracy of this system when we apply it to many persons. Through the discussion, it can be seen that this system have enough accuracy.

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We would like to make a device which could help the hemiplegia to transfer to bed, wheelchair and so on, by themselves. We investigated how the human body moved when people transferred from one chair to another chair. The movement of healthy subjects and hemiplegic subjects were measured by a three-dimensional movement analysis system and center of gravity measurement system. As a result, the measured date of light hemiplegia were similar that of healthy subjects. However, the measured data of medium hemiplegia were different from that of healthy subjects, and it was supposed that this difference was due to subject's residual muscle power.

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Standing-up from a chair is one of fundamental motions in everyday life. However, some elderly people are difficult to stand up. Therefore, we would like to develop a portable device which could assist standing-up. In this paper, first, we produced a device which could analyze standing-up motion from a chair. Next, some data such as ground reaction force, the sway paths of the center of gravity, were measured using this device while standing-up motion. And also, we performed a pull test in which standing-up force was measured in order to confirm whether or not calculated standing-up force was equal to measured one. Lastly, the data of the elderly were compared with that of younger subjects.

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In order to make clear the differences in trunk controlling ability between the young and the elderly, we developed an evaluation system using a force plate and CRT monitor. In the present experiment, 14 young-male, 17 elderly-female and 15 elderly-male subjects participated. The subject stands on the force plate in front of CRT monitor, and controls postural stability following a target dot which traveled on the CRT monitor. Both the postural sway of the subject and the target dot were displayed simultaneously. The length of postural sway and time course were respectivery recorded during the expriment. The current results indicated that 1) the trunk controlling ability of the young was higher than that of the elderly, 2) all of the subjects showed higher trunk controlling ability in forward than in backward, 3) the trunk controlling ability in horizontal is the lowest in the elderly subjects.

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We have developed an equipment for transfer of a patient between bed and stretcher. It became possible to transfer by controlling two plates and a belt without friction or a physical stress. Position adjustment of a patient became possible by dividing equipment into four modules and controlling eight motors. The drive part was equipped with a safety system. The equipment automatically stops at dangerous situation, such as pinching a hand and a finger. Evaluation by clinical staffs at the university hospital was conducted to exact the requirement for improvement.

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The authors have developed a mouth opening and closing training robot system with a 6-DOF parallel mechanism. As one of its applications, the authors have developed an intermaxillary traction therapy system which can tract a patient jaw joint as a non-physiological movement in order to help regenerate its normal lower jaw joint tissue. This training is effective for patients suffering from a disease called "open bite" in which the patients cannot close their jaws completely. The authors also applied a developed mastication robot to a quasi-patient and confirmed a movement of the training robot.

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By using our crawl-type mechanism, we have been developed stairlift, powered wheelchair and slope-car which can move up and down along staircase or slope. Elderly or handicapped people can easily and effectively go to desired place by using these devices. Carrier plate using crawl-type mechanism is supported and traveled on two traction guides and is driven by reaction force caused on one roller attached on motor driven disc and drive guide set up between the traction guides. Each traction guides roller were composed of one pair rollers hold on each traction guide. This structure is useful for moving along helical staircase, but moving stability along the horizontal traction guide is poor relative to moving on the slope parts. In order to raise up the moving stability on the horizontal one, 3 roller-type is adoped instead of one pair roller type. Shape modification of circular arc part, needed for connecting the guide whose slope angle is different, of traction guide is presented here.

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We propose a reconfigurable control module for welfare systems using SOPC (System On Programable Chip) technique. This control module was reconfigurable. This feature was very useful for the development of control systems. We also developed some parameterized controller components. ・ΔΣADC and ΔΣDAC : analog signal interface・PWM, PWC and Encorder Counter : digital signal interface・CORDIC module and PID module : improve the sampling rate Users can develop various type controller with this control module core and some parameterized components.

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We propose a health monitoring robot which seeks an unconscious body condition measurement in daily life. The robot interacts with humans and measures human's body conditions through physical contact. This paper describes on a prototype robot in which we embedded some near-infrared sensors for detecting plethysmogram pulses. Those embedded sensors has a dumper system for keeping the contact state stable between the sensor and the tissue. The prototype robot consists of mechanical parts and foliage plants and we assume that the robot prompts humans to take care of it. Experimental results showed that the robot monitors plethysmogram pulses in some situation including physical contact with human.

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In this paper, a new walker for rehabilitation using omni-directional roller wheel is proposed. The proposed walker are have them as follows. (1) It has the function of which the safety under training is guaranteed. (2) The walker is moved and is made to not only front but also omni-direction. Finally, it was possible to confirm these two merits by the experiment.

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We have been developing exoskeletal robots to assist the motion of physically weak persons such as elderly persons or slightly disabled persons in daily life. In this paper, we propose a forearm motion assist method with an exoskeleton robot for physically weak persons. The robot automatically assists the human forearm motion mainly based on the skin surface electromyogram (EMG) signals in the proposed method. Fuzzy-neuro control has been applied to realize the sophisticated real-time control of the exoskeleton robot. Experiment has been performed to evaluate the proposed method.

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Though a lot of robots play in factories as only industrial use, in most cas es, they are specialized for simple work and are not flexible. But an appearance of the robots which can do general-purpose work is expected for the coming aging society. Social robots should work in human society, they can use tools for human, they must behave like human. For the dexterous works, we considered several of methods, we adopt the imitation of human behaviors that are guaranteed realization. We have developed dual five-fingered hand arm robot with distributed touch sensor and "State Action Event Network (SAEN)"as a simple robot task programming system. We examine the usefulness and problems through making works of actual robots with these systems and we have extended and improved functions. In these days, the more advance in society of hearing-impaired person increases, the more importance of communication with them increases. For doing this, we have adopt sign language. It can tell contents without tools as fast as speaking. But ordinary person cannot use it, because they hardly acquire sign language. So the realization of communication hearing-impaired person with ordinary person is expected with robot.

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Wheels and crawlers have been used as the locomotion mechanism of welfare systems such as wheelchairs and walk support machines. However, they are difficult to be employed in human-living environments. The purpose of this research is to develop a multi-purpose locomotion system for human-robot symbiosis. The locomotion system can take on a human and support his / her walk on the slopes and stairs. We have developed a biped locomotion system that consists of a waist and two legs with parallel mechanisms, and realized dynamic walking, sharp turning, outdoor walking and walking with 50kg payload.

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In this study, we have developed a mat which has a function to prevent bedsore. In order to distribute the pressure applied to the body, we have proposed a body pressure distribution strategy by using 12 mats driven independently. And the eaectiveness of the proposed method is conarmed through some experiments. In this paper, arst of all, the structure of the Medical Care Mat is shown. Afterwards, the eaectiveness of the propose method is conarmed through experiment.

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A one hand drive wheelchair, which has a manipulation mechanism with a triple ring and a power assist function, is developed. In this paper, in order to reduce a load of user and realize a comfortable manipulation, a power assist rule, based on manipulation torque and the velocity of wheelchair, is proposed.

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In this paper, we discussed the power assisting system for a walking chair. The power assisting system (PAS) can detect human's intention and control the assisting-motor to generate the assisting torque for driving walking chair by human. In the previous research, power assisting systems have been classified into two types, one is torque-combination type and another is speed-combination type. In this paper, we propose a new control method for speed-combination type, which provides a stable variation of speed when human's driving has variation of speed and it has been confirmed through experiments. Finally, we discuss the merit and demerit of the PASs based on the experimental results.

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The power assist equipment for the lower limbs disabled to move in erect posture that consists of a pair of "elastic crutches, ""mobile platforms" and a "power prosthesis" has developed. In order to realize "the traveling in erect posture", "the standing up from seating position" and "the going up and down stairs" by the coordination operation of three equipments, the length of the crutches, the joint angles, and the torques, are examined through simulations. In addition, after confirming basic motions of three equipments through experiments, the automation for the coordination operation is studied.

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We develop a wire-driven wrist assist supporter with non-linear spring devices. The supporter can move a wrist freely instead of fixing while assisting torque loading a wrist. We expect that it is available in daily life, rehabilitation and so on. Such a supporter needs agility, flexibility and an arrangement design of power sources. A wire-driven mechanism is superior in agility and a power arrangement. Moreover, non-linear spring device installed to a wire gives the mechanism flexibility. A torsion spring is built in to the device, and space is not occupied on account of installing it in the same direction as a wire. This paper describes a basis analysis of a wire-driven mechnism, structure and characteristics of non-linear spring device with a torsion spring, a force feedback control system, and experiments of the supporter.

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