Backstepping sliding mode stabilization controller for underactuated unmanned surface vehicle based on disturbance observer

This paper studies the stabilization control of underactuated Unmanned Surface Vehicles (USV). Firstly, a three-degree-of-freedom (3-DOF) of underactuated USV in complex sea conditions is established. On this basis, a backstepping sliding mode stability controller based on disturbance observer (BSMC-NDC) for USV is designed. The backstepping sliding mode control strategy is used to achieve the stabilization control effect, and the hyperbolic tangent continuous sliding mode is used to reduce the controller jitter. Aiming at the complicated ocean disturbance in the process of USV stabilization, a 3-DOF disturbance observer based on exponential convergence is designed. The effectiveness of the control system is fully verfied by comparing the simulation results of similar controllers. Specifically, simulation results show that the proposed controller can achieve the USV stabilization control and solve the jitter problem in the sliding mode control process.