Full-State Regulation Control of Asymmetric Underactuated Surface Vehicles

In this paper, a challenging problem of full-state regulation control (FSRC) for an asymmetric underactuated surface vehicle (AUSV) suffering from disturbances is solved. The FSRC objective is divided into two sub-tasks, i.e., reaching trajectory (RT) guidance and tracking controller synthesis with underactuation and disturbances. The RT guidance is achieved by devising a circular orbit (CO) accurately passing through the desired full-state waypoint (FWP). Using a series of coordinate transformations, tracking error dynamics are shaped in a translationrotation cascade form with respect to the CO-center frame. Using finite-time approach, lumped disturbances are accurately estimated by exact observers, which facilitate synthesizing surge and yaw controllers. By creating a new coordinate, translation subsystem is converted to a lower-triangular form. Combining with backstepping technique, cascade analysis and Lypunov approach, translation and rotation controllers are derived systematically, and render the entire closed-loop FSRC system globally asymptotically stable. Hence, the AUSV is regulated to the desired FWP. Simulation studies on a benchmark AUSV are conducted to demonstrate remarkable performance.