Yoji Yamada

Skil Mate wearable exoskeleton robot

A wearable exoskeleton robot, Skil Mate, is a new concept that can assist skilled workers in power as well as in skill. Skil Mate is composed of servo mechanisms and haptic devices (tactile or slipping-off sensors/displays), so that it can follow the workers movement. Skil Mate is suitable for work in hazardous environments such as in space, under sea, etc. The goal of the project is to develop a prototype model of the wearable robot for a spacesuit, which consists of an upper torso assembly and a pair of arms with gloves.

Development of a Wire Driven Walking Assist Device by Muscle Strength

The elderly sometimes fall due to the decreasing of dorsal flexion. Thus, a wearable assist device which increases dorsal flexion to reduce the risk of tripping is developed. This device applies torque to foot joint from strong muscle through wires attached on the whole body during the swing phase. To improve the efficiency of the assist, wire paths were optimized by joint torque simulation. In this study, two wire path patterns which apply dorsal torque in swing phase were considered. As a result, the wearable assist device we developed successfully increased dorsal flexion and minimum foot clearance during swing phase.

Effect on Corner Curving Motion Caused by the Restriction of Out-of-Sagittal-Plane Motion Applied by a Wearable Device

For developing a mechanism which can enable an assist device to turn a corner naturally, we analyzed the effects on curving motion from the restriction of hip joint. To check the effects of restricted out-of-sagittal-plane motion, subjects wore a wearable device which can restrict the hip joint. Then, Subjects walked along a curved path with or without the restriction. In the restricted condition, the rotation and adduction or abduction angle of hip joint was decreased. This lead subjects to change their movement of COM. This potentially causes fall during outer footstep.

An Analysis of Fall Motion and Estimation of Severity against the Tripping During Gait

Relationship between the limitation of the fall avoidance motion and severity of the fall should be explained because the fall is one of the most severe risks in the industrial site. However, the study which recorded whole of the fall motion is rarely performed because of the difficulty of reproducing fall in the laboratory due to the safety concerns. In this study, the fall motion, which was caused artificially, was recorded as long as possible within the bounds of safety. Then, the successive motion until the ground contact was simulated. As a result, the position and velocity of the ground contact could be connected to the fall avoidance motion, which means the step length after tripping, and the motion during the fall, forward tilt of the body and vertical velocity of CoM.