Adaptive sliding mode impedance control in lower limbs rehabilitation robotic

This paper proposes a approach to regulate both position and contact force of lower limbs rehabilitation robot for patients with walking disabilities. The methodology is developed based on the sliding mode impedance control with adaptive switching gain. The stability of the control system is proved in theory, which ensures the tracking performance in the presence of model uncertainties and variable active force from rehabilitation patients. Simulations results show that the approach can apply suitable forces on the leg so that lower limbs rehabilitation robot moves on a desired trajectory and achieve an accurate balance between the position and force control.