Multidirectional Gravity-Assist and Active-Following Lower-Limb Exoskeleton Robot for Gait Neurorehabilitation

Abstract

Gravity-supported gait interactions and active user-participation have promoted the gait recovery for individuals with spinal cord injury or stroke. However, devices or systems that concurrently integrated with these functions have received comparatively little attention. In this paper, a versatile lower-limb rehabilitation exoskeleton robot system with gravity-assist and active-following is developed for the gait training, which enables the subject with motor disorders to walk naturally. The developed system consists of three main components: 1) an active-following walker based on the visual feedback, 2) a gravity-assist cable-driven parallel platform with multiple tension sensors, 3) an eight degree of freedoms (DoFs) lower-limb exoskeleton. Further, the kinematics and dynamics of the whole system are analyzed and a robust adaptive control strategy is designed. Finally, an experiment of the human gait trajectory-tracking is performed to verify the effectiveness of the proposed system.