Sliding mode setpoint control of an underactuated surface vessel: Simulation and experiment

A sliding mode control law is presented and experimentally implemented for setpoint control of an underactuated autonomous surface vessel. The control law is developed by defining a single sliding surface for orientation stabilization that determines the required yaw moment and three additional surfaces that determine the surge force. The trajectories are shown to converge to each of the surfaces in finite time and the sliding phase is shown to be asymptotically stable. Two setpoint control scenarios are simulated and then demonstrated experimentally. The experimental results show that the surface vessel converges to the desired setpoint with reasonable accuracy.