A Simple Robust Stabilization Control Law of Underactuated Surface Vessels

In this paper, a new time-varying static feedback control law is proposed solving the stabilization control problem of underactuated surface vessels. The control idea comes from the driving experience of human. By employing Lyapunov's direct method and Barbalat's lemma, it is proved strictly that the proposed controller globally asymptotically stabilizes the underactuated surface vessel to desired constant location and orientation, and forces its velocities to zero. The resulting controller is just a very simple linear function of forward/lateral position and orientation errors, without any modeling parameter. Compared with the previous work, the controller is more practical in real-word applications because of the unneeded velocity sensors and the robust property with respect to model parameters. Effectiveness of the proposed controller is demonstrated by numerical simulation.