Finite-Time Disturbance Attenuation Tracking Control of Flexible-Joint Robots Based on CTSMC

Abstract

A robust finite-time disturbance attenuation tracking control strategy of flexible-joint robotic systems affected by unpredictable matched and unmatched time-varying disturbances is presented in this work. By considering all the disturbances as an unknown total time-varying disturbance, a dynamic model with the flatness description of the FJR is firstly deduced. Then, a new dynamic terminal sliding mode surface is designed with the assistance of the estimates from a constructed sliding mode observer (SMO). Meanwhile, the continuous terminal sliding mode control (CTSMC) technique is employed to develop a finite-time disturbance attenuation control methodology. Besides, the finite-time stability of the closed-loop system acting on the proposed control framework is guaranteed. Finally, simulation results on a two-link FJ robot demonstrate the superiority of the specially devised constructed control approach.