Joysticks can be used to effectively control a powered wheelchair. The joystick is the most common control interface between the user and the wheelchair. By improving performance of powered wheelchairs and other assistive devices, the joystick, one of the man-machine-interface, becomes to be needed for more delicate operation. In such situation, for elderly persons with functionally insufficient upper extremity and handicapped persons with involuntary motion of arm, there is a possibility of causing serious problems as steering mistake. One of the effective methods is to set the mechanical stiffness characteristics of the joystick according to operator's stiffness characteristics.

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The purpose of this study is to develop a non-contact method to evaluate the heart rate and respiration rate simultaneously for elderly people at home, using single phtosensor. The respiration rate and the heart rate were detected from power spectra using Fast Fourie Transform(FFT)of the laser amplitude, which was reflected fro the chest walls of rabbits under He-Ne laser irradiation with and without a cloth on the chest. The rabbit with a cloth on the chest wall is a model for human with clothes. The heart rate evaluated by this method agreed well with the rate derived by electrocardiogram. The respiration rate also correlated with the manually measured respiration rate. This method appears promising as a non-invasive method for monitoring the heart and respilation rate of aged persons.

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Red blood cells in cardiopulmonary devices are subjected to unphysiological range of physical parameters . It is well known that the damage to red blood cells has relationship with physical parameters . However, a mechanism of hemolysis caused by the relationship is not clarified . The purpose of this study is to investigate the relationship between physical parameters and hemolysis by in vitro experiments . Bovine blood mixed with an anticoagulant was subjected to physical parameters: shear rate(0, 500, 1500s^-1), pressure(0, ±200, ±400, ±600 mmHg)and temperature(21, 28, 35°C). In consequence of these experiments, significant hemolysis was not observed at a shear rate of 0 or 500s^-1. At a shear rate of 1500s^-1, pressure more than200mmHg or less than-200mmHg induced significant hemolysis. In contrast, no hemolysis was observed under the other experimental conditions. In conclusions, it was found that pressure became an influential parameter on hemolysis when the shear rate was high. In addition, it was considered that the effect of pressure on hemolysis depended on the level of shear rate.

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Welfare equipment and services are the basic issues involved in the civic life in all the countries, and we have therefore investigated research projects and services being promoted in Europe and North America for elderly people and handicapped persons for the possible joint use of data on such research and development activities as the basis for technical information which can be utilized on an intemational scale through the intemational network. We have then considered the possible provision of an interface for access to the welfare equipment database through the Internmet and the personal computer as an important step toward establishing a highly reliable database which will be easily available to anyone.

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