Yaw channel control of an autonomous underwater vehicle using sliding mode control based on an extended state observer

A highly uncertain and time-varying ocean environment demands a robust control strategy to accomplish the autonomous underwater vehicle (AUV) mission. This paper addresses the sliding mode controller based on linear extended state observer (SMC-LESO) control strategy on the linearized yaw channel model of an experimental MAYA AUV. Trajectory tracking control problem is chosen to control the yaw channel of the vehicle in the presence of system non-linearity, modelling uncertainties, unmodelled dynamics and external disturbances treated as a total disturbance/uncertainty. LESO is designed to estimate the total disturbance/uncertainty online along with the system states. SMC is designed on the basis of the estimated value. The proposed control scheme is robust against total disturbance, and it tracks the desired trajectory effectively. The closed-loop stability of the proposed controller is validated in the sense of Lyapunov. The trajectory tracking performance is analyzed against control objectives. Simulation studies have been carried out to examine the efficacy and applicability of the proposed control scheme.