Control of Self-Balancing Lower Limb Exoskeleton for Various Wearers Under Dynamic Deformation

Unlike conventional lower limb exoskeletons that rely on external devices, the self-balancing exoskeletons enable individuals with diverse mobility impairments to regain the ability to walk. Current self-balancing exoskeletons struggle to balance between interpersonal adaption and compliance. Adjustments to parameters are often required when accommodating different wearers, and dynamic deformations pose significant challenges in the performance of these exoskeletons. This article proposes a control approach of self-balancing lower limb exoskeleton for various wearers under dynamic deformation, which includes two controllers. First, we propose a new informer-based feedforward deformation compensator, which could reduce the average position error and attitude error by 79.04% and 84.95%, respectively. Then, we design a compliance controller based on impedance control that can be applied to different wearers. At last, the self-balancing exoskeleton walking experiments with seven subjects (five male, two female) are conducted. The results reveal that this study achieves stable walking with the self-balancing exoskeleton loaded range from 0 to 73 kg.