Development and Analysis of a Novel Bio-syncretic Parallel Hip Exoskeleton Based on Torque Requirements

This paper presents a novel bio-syncretic parallel hip exoskeleton (BsPH-Exo) to address the rehabilitation exercise needs of individuals with lower limb motor dysfunction. BsPH-Exo has six degrees of freedom and can generate all three kinds of rotations that the hip joint can naturally realize. BsPH-Exo effectively solves the problem of misalignment between human and exoskeleton joints, eliminating the need for patients to perform any alignment operations. Considering the varying maximum torque requirements for hip joint rehabilitation in different directions, the limbs of BsPH-Exo are specially arranged to ensure that the maximum torque provided by BsPH-Exo in each direction follows the same law as that of the required torque. As a result, BsPH-Exo exhibits excellent output torque performance, specifically in the flexion/extension direction. Moreover, BsPH-Exo demonstrates weak coupling characteristics in the flexion/extension direction and decoupling characteristics in the adduction/abduction direction, which reduces the difficulty in its control. Compared to currently available parallel hip exoskeletons, BsPH-Exo has several distinct advantages that make it particularly well-suited for rehabilitation applications.