A study on a waist power assist suit for a caregiver to prevent lower back pain

We currently develop a waist power assist suit for a caregiver that physically supports his/her lifting and twist motions to prevent lower back pain. In our earlier studies, a DC motor-driven mechanism has been proposed where two motors that are attached at both sides of lower back generate the assistive torque for a lifting motion by driving them in the same direction, and for a twist motion by driving them in different directions. In this paper, we address to reduce the suit weight, refine the design, and to improve how to put on the suit. Regarding a signal processing for motion recognition, we also have studied a surface EMG-based signal processing with support vector machine. Although the recognition rate with the sensing system is promising off-line, the algorithm is quite complicated for implementation to a microcomputer. In this paper, we propose a simple signal processing for motion recognition based on surface EMG.