Event-triggered sliding mode controller design for lower limb exoskeleton

This paper investigates a sliding mode control method based on event-triggered strategy for lower limb exoskeletons. Firstly, the dynamic model of the lower limb exoskeleton is established. Secondly, in order to deal with system uncertainties and external disturbances of the exoskeleton, a sliding mode controller is utilized to keep the system tracking the reference trajectory stably and smoothly. An continuous event-triggered strategy is designed for saving communication resources and energy consumption. The proposed event-triggered sliding mode control can guarantee that the system is asymptotically stable and the lower bound of the inter event execution time has been derived, which ensures that Zeno behaviour is avoided. Finally, simulation results are provided to show the effectiveness of the proposed control scheme.