CPG-based gait planning and model-independent adaptive time-delay control for lower limb rehabilitation exoskeleton robots
Zhe Sun
Weixin Chen
Bo Chen
Hai Wang
Jinchuan Zheng
Zhihong Man
Abstract：Focusing on the rehabilitation training of hemiplegia patients, this paper proposes a gait-planning strategy based on a central pattern generator and an adaptive time-delay control scheme that utilizes recursive terminal sliding mode for lower limb rehabilitation exoskeleton robots. The central pattern generator network plans a reference gait trajectory for the affected leg, synchronized with the movement of the healthy leg. The proposed adaptive time-delay control scheme possesses a model-independent property due to the mechanism of time-delay estimation, with adaptive control gains that enhance the resilience against system perturbations and a recursive terminal sliding mode control component to achieve a fast convergence rate. According to the Lyapunov stability criterion, it is proved that the gait trajectory-tracking error is uniformly ultimately bounded. Experiments are conducted on a lower limb exoskeleton experimental platform, and the experimental results demonstrate the effectiveness and superiority of the proposed strategies.
Keywords：Lower limb rehabilitation exoskeleton robot(LLRER)Central pattern generator(CPG)Time-delay estimation(TDE)Sliding mode control(SMC)
Publication Date：2025-12-30
Online Publishing Date：2026-01-09(First online date of this platform, not the publication date of the document)
Pages：13( 650-662 )