Finite-Time Trajectory Tracking Control of Under-Actuated Autonomous Surface Vessels Based on Non-Singular Terminal Sliding Mode

In this paper, the trajectory tracking control problem of under-actuated autonomous surface vessels is investigated. Both the parameter uncertainties and environmental disturbances are considered in system dynamics. By combining a trajectory planning method and the non-singular terminal sliding mode control technique, two global finite-time stabilising controllers for position tracking, ie. the surge controller and the lateral motion controller, are proposed. In order to reduce the chattering, the boundary layer method with a novel saturation function is employed to derive two modified continuous controllers. Simulations demonstrate the effectiveness of the proposed control scheme.