Adaptive Sliding Control for Lower Exoskeleton Robot Driven by The Series Elastic Actuator

Abstract

The Series elastic actuators (SEAs) are known to offer a range of advantages over stiff actuators for human-robot interaction, such as passive mechanical energy storage, low mechanical output impedance, impact resistance and safe human-machine interaction in the research domain of exoskeleton robot, mobile robot and manipulator etc. Despite some the SEA-based lower exoskeleton robot have been implemented and developed very well on the domain of control and interactions with the subject, however the control methods of the uncertainties of robotic exoskeleton based on SEAs have not been proposed and solved very excellently. The purpose of this paper is to design a control method for elastic actuation of the lower exoskeleton robot, which can enhance performance of the human-machine interactive system and assistant human walking steadily. Take full account of the uncertainties in both robotic exoskeleton dynamics and SEA dynamics, therefore we proven the stability of the proposed controller which could enable to ensuring the safe of human-machine interaction by applying the Lyapunvo method. An experiment has been conducted and presented for illustrating the reliability and security of the proposed controller.