Robust Adaptive Sliding Mode Control of Upper-Limb Rehabilitation Exoskeleton System with Uncertainties

Uncertain robotic manipulator systems, known for their high nonlinearities, unmodeled dynamics, and uncertainties, are the subject of this paper. Based on the terminal sliding mode control algorithm and its nonsingular design method, a new robust control scheme is introduced to ensure fast and finite time convergence to the desired state. The upper bounds of unknown system uncertainties are estimated using adaptive control. The stability of the proposed control strategy is confirmed by the Lyapunov theory, and its effectiveness is tested on a two-degrees-of-freedom robotic manipulator. Robustness and rapid convergence, as well as reducing the controller's high-frequency commutation effect, are proved.