Gait Tracking for Lower Extremity Exoskeleton Based on Impedance Control

In the process of human and exoskeleton cooperative movement, precise tracking of joint position will significantly enhance the cooperation between user and exoskeleton. Especially in the support phase, the exoskeleton contacts with the environment, not only to make the exoskeleton adapt to the changes of the environment, but also to track of the position. So, a position-based impedance control strategy is proposed. In this paper, dynamic model of exoskeleton system in the support phase is established, an impedance-based gait tracking controller is designed and also proved the stability of the closed-loop system.