Study on the Control Method of Knee Joint Human–Exoskeleton Interactive System

Abstract

The advantages of exoskeletons based on the Bowden cable include being lightweight and flexible, thus being convenient in assisting humans. However, the performance of an exoskeleton is limited by the structure and human–exoskeleton interaction, which is analyzed from the established mathematical model of the human–exoskeleton system. In order to improve the auxiliary accuracy, corresponding control methods are proposed. The disturbance observer is designed to compensate for disturbances and parameter perturbations in the inner loop. The human–exoskeleton interaction feedforward model is integrated into the admittance control, which overcomes the limitation of the force loading caused by the friction of the Bowden cable and the change in stiffness of the human–exoskeleton interaction. Furthermore, an angle prediction method using the encoder as the signal source is designed to reduce the disturbance of the force loading caused by human motion. Finally, the effectiveness of the design method proposed in this paper is verified through experiments.

A Proof of Principle Study Conducted by Community-Dwelling Seniors Using a Novel Passive Gait Assist System

“…Sci. 2024, 14, 1363 2 of 10 Due to added inertia and the wearability and comfort issues of hard exoskeletons, soft-type exoskeletons comprising textiles and Bowden cables have also been developed to boost users' mobility [32][33][34][35][36]. However, both types are relatively expensive and require specialist assistance; thus, they have fallen short of being immersed in the rehabilitation scene.…”

Position control of electro-hydraulic servo system using active disturbance rejection control for upper-limb exoskeleton

“…Upper-limb exoskeleton robots are generally applied in a variety of different fields, such as rehabilitation robots [1][2][3], assistive robots [4][5][6], human amplifiers [7,8] and other uses. Robotic exoskeleton is the complex multi-input and multi-output (MIMO) with time varying dynamics and highly coupled nonlinear [9].…”