2945 Development of a Power Assist Mechanism Attached to the Upper Limb Using Differential Gears

Abstract

We developed a power assist mechanism attached to the upper limb, using differential gears. It is being developed for nurses who care an old person being bed ridden, or workers who often lift loads up and down. 2 motors behind shoulder provide motive power to drive shoulder joint and elbow joint, and differential gear makes it possible to divide the power between them effectively. Differential gear system can realize the concentrated drive system, which can reduce the load of shoulder or elbow, comparing to the distinct power motor system attach on each joint. Also, differential gear reduces backlash. We designed the mechanism can assist by 8kg with arms straightened forward horizontally. Experimental result shows the good characteristics following to the angle target.