A fixed-time nonsingular fast terminal sliding mode control scheme with time-varying sliding mode surface

Abstract

This article proposes a fixed-time nonsingular fast terminal sliding mode control scheme with time-varying sliding mode surface for a class of second-order uncertain system. The control scheme makes the tracking error converge to the origin in fixed time without singularity problem and guarantees fast convergence rate given any initial states. In addition, the proposed control scheme ensures system states to converge to the origin instead of a neighbourhood of the origin which is so called practical fixed-time convergence. As a result, high precision of the trajectory tracking is guaranteed by the control scheme. A comparative simulation with a two-link manipulator is given and the results show that the proposed control scheme can achieve a good performance.