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.
