Design and Patient-Oriented Control of A Rehabilitation Assistance Upper Exoskeleton

Abstract

Inspired by the difficulties behind specification requirements as well as realizing the applicable capacity of upper exoskeleton robots, this paper presents the design and development of an original prototype of Rehabilitation Assistance UPper EXoskeleton (RAUPEX). The exoskeleton is designed through the analysis of human's upper limb biomechanics and dynamics. Based on the requirements of human joint power, the solutions of mechanism and actuator for the exoskeleton are drawn. During development of the exoskeleton, a basic control hardware is built to ensure real-time control performance besides a custom-built control panel for users. A patient-oriented control strategy allows RAUPEX to assist patients with various disability level in rehabilitation. The robot's applicable efficiency has been evaluated through rehabilitation training tests on healthy persons as quasi-patients via fundamental criteria in the exoskeleton development. Normalized square sum of angular operator-exoskeleton errors that is $(25.3\pm2.45)\times10^{-3}$ for active control and is $(5.89\pm0.42)\times10^{-3}$ for passive control. Moreover, the resulting operator-exoskeleton interaction force which is maximum of $7.75$ N at upper arm and $4.32$ N at lower arm enables RAUPEX to accurately assist rehabilitation exercises without discomfort. Over $87\%$ of experimental participants claimed to feel comfortable which proves the developed exoskeleton has the potential to increase efficiency and adaptation to users during rehabilitation procedure. DOI: 10.61416/ceai.v25i3.8341