Robust bounded compensating control for path-following of USV via the switching L1-VS guidance

For the path-following control problem of the Underactuated Surface Vessel (USV) under the unknown marine disturbances, this note proposes a robust bounded compensating control algorithm based on the switching L1-VS (L1 Virtual Ship) guidance. The control strategy is divided into two modules: guidance and control. For the guidance module, the control difficulty caused by the time varying reference signal is alleviated by the L1-VS guidance technique with switching mechanism. For the control module, a robust bounded compensating technique is considered to approximate the model nonlinear terms, effectively reducing nonlinear approximation error while ensuring the low designed complexity of control law. Besides, the Event-Triggered Control (ETC) technique with dynamic/static mixed threshold is used to handle the problem of communication load and actuator wear. Then, the GUUB (Global Uniform and Ultimately Bounded) stable of the control system is proved based on Lyapunov theorem. Finally, an experiment simulating the narrow-channel crossing mission is conducted, where the robustness and superiority of the algorithm is verified.