Design and Analysis of a Hybrid-Driven Ankle Joint for Lower Extremity Exoskeleton Robots

Abstract

In order to improve the safety and comfort of human-machine interaction and its adaptability to complex unstructured environments, a new type of ankle joint based on series of elastic drive and rigid drive hybrid was designed between the motor and exoskeleton robot. Linear spring groups were introduced to achieve flexible driving and absorb the ground reaction force and other impact vibration. At the same time, a disk brake device was designed to retain the rigid drive function to quickly and accurately respond to the motion of the human ankle joint and reduce human-machine movement deviation. The dynamic model of the ankle joint was established. The stability of the hybrid driver under different parameters were obtained through frequency domain analysis. Through simulation experiments, the accuracy and effectiveness of the model were verified.