Finite-time tracking control for autonomous underwater vehicle based on an improved non-singular terminal sliding mode manifold

Abstract

This paper investigates the finite-time tracking problem for autonomous underwater vehicles (AUVs) in the presence of external disturbance and modelling uncertainty. A finite-time tracking control scheme is proposed based on an improved non-singular terminal sliding mode manifold. Firstly, in order to achieve finite-time stability and avoid singular problem, a continuous and smooth non-singular terminal sliding mode manifold is designed based on a piecewise function. And then a continuous control law is designed by indirectly estimating the bound of the general uncertainty, to compensate the external disturbance and modelling uncertainty. Based on the Lyapunov stability analysis, it is verified that the tracking error can converge to a certain range near zero in a finite time. Finally, the proposed control scheme is applied to ODIN AUV and compared with another two finite-time tracking controllers. Simulation results show the effectiveness of the proposed control scheme.