The Purpose of this study is to detect eye-gazing points during driving a wheelchair through the image sequence analysis of video frames. The performlances can be measured without restrictions of specific devices such as any accessories and sensors, which were put on a body. Images obtained with two video cameras allow the algorithm with two-dimensional multi resolution analysis through wavelet analysis to extract boundaries of right and left irises. Their three-dimensional positions and directions were estimated through direct linear transformation(DLT)technique. The eye-gazing point was evaluated through the relationship between the vertical vector of iris and line-of-sight. Consequently, Some preliminary results were presented to illustrate the detecting error of eye-gazing point.

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A standard wheelchair was remodeled in order to improve the operability on the level difference, slope and side-slope. The caster was replaoed with a crawler. The crawler was the caterpillar and facilitated climbing over the level difference. The direction of the crawler could be fixed for the rectilinear propagation on the side-slope. The brake pad of rear wheel was replaced with a one-way clutch with a pin for stopping its rotation. That prevented the reverse run on the slope. The remodeled wheelchair was evaluated by means of both semantic differential(SD)method and measurement system. The system was able to measure either the pressure distribution on handrim or the holding state of handrim. The sensitivity tests revealed that the remodeled wheelchair was serviceable. The measurement system indicated that the remodeled wheelchair extended the released time of the handrim when the wheelchair was on the slope. On the side-slope, the remodeled wheelchair advanced at higher velocity than standard one, because there was no need to take evasive action for going straight.

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A pillow-shaped resptratory monitor has been developed as a vital monitor. The monitor evaluates changes in weight of head corresponded to respiration precisely. Resphlatory rate and time of body movement, and pillowoff condition can be monitored. In this paper, respiratory rates were compared between this monitor and a polysomnograpy for ten patients with sleep disorders. This monitor can evaluate central apnea but not obstructive apnea.

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To improve the shoulder disarticulation prosthesis for single arm amputee, aesthetic, user-friendliness, and light-weight device is expected. This paper proposes a joint mechanism design with shape memory alloy(SMA)actuator system as a solution to the challenge. Our prosthetic arm is designed for cooperative work in drafting action, where the prosthetic arm works stationary holding the ruler. We set the arm's specification by tracking the movable range of the arm holding the drafting ruler on the table. From this analysis, we propose a passive type hybrid prosthetic arm. The locking mechanism of the joint system is activated by the recuperative strength of the SMA. A forced-cooling operation for the thermal control of the SMA wire is discussed to improve the repeatability of the joint mechanism control. The experimental result showed that the system cuts40% of the cooling term for the joint positioning and improves the usability of the prosthetic arm. A control system for the SMA joint mechanism is presented to be mounted in the arm.

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