A novel approach towards control of exoskeletal systems as an assistive device for human's upper extremity

Abstract

With increasing importance of exoskeletons as rehabilitation apparatuses, suitable and delicate control strategies has received much attention. In order to control the exoskeleton, there should be a complete understanding of torques produced by the limb itself which makes the musculoskeletal modeling of the limb essential but also complex. In addition, the musculoskeletal model can be used to discover the user's desired movement to control the exoskeleton. In this paper a complete musculoskeletal model for the elbow with two degrees of freedom is developed and simulated. Next the model is used to determine user's desired movement. Finally based on this evaluation, an exoskeleton model is controlled by PD and Lyapunov-based controllers. The results show suitable resemblances between the control efforts of natural arm movement and the exoskeleton interfaced system.