Trajectory tracking for an articulated intervention AUV using a super-twisting algorithm in 6 DOF

Abstract

The articulated intervention autonomous underwater vehicle (AIAUV) is a slender, multi-articulated, underwater robot that is equipped with thrusters, i.e. an underwater swimming manipulator (USM). For the AIAUV to be able to move in confined spaces and perform intervention tasks, it is essential to achieve good station-keeping and trajectory tracking performance for the AIAUV by using the thrusters and by using the joints to attain the desired position and orientation of the vehicle. In this paper, we propose a sliding mode control (SMC) law, specifically the super-twisting algorithm with adaptive gains, for the trajectory tracking of the joints angles and position and orientation of the base of the AIAUV, and we consider this tracking problem of the AIAUV in 6 DOF. A higher-order sliding mode observer is proposed for state estimation. Furthermore, we show the ultimate boundedness of the tracking errors, and we demonstrate the applicability of the proposed control law with simulations.