Open-closed Iterative Learning Control Algorithm for Exoskeleton Rehabilitation Purposes

Abstract

The paper designs an appropriate iterative learning control(ILC) algorithm based on the trajectory characteristics of upper exoskeleton robotic system.The procedure of mathematical modelling of an exoskeleton system for rehabilitation is given and synthesis of a control law with two loops. First (inner) loop represents exact linearization of a given system, and the second (outer) loop is synthesis of a iterative learning control law which consists of two loops, open and closed loop. In open loop ILC sgnPDD2 is applied, while in feedback classical PD control law is used. Finally, a simulation example is presented to illustrate the feasibility and effectiveness of the proposed advanced open-closed iterative learning control scheme.