Position Tracking for a Nonlinear Underactuated Hovercraft: Controller Design and Experimental Results

This paper addresses the position tracking control problem of an underactuated hovercraft vehicle. A nonlinear Lyapunov-based tracking controller is developed and proved to exponentially stabilize the position tracking error to a neighborhood of the origin that can be made arbitrarily small. The desired trajectory does not need to be a specially chosen trajectory (e.g., a trimming trajectory). In fact, it can be any sufficiently smooth bounded curve parameterized by time. The nonlinear controller has been experimentally validated on the Caltech Multi-Vehicle Wireless Testbed (MVWT), a platform for development and implementation of novel singleand multiple-vehicle control designs. Experimental results are given for tracking of prescribed trajectories and for target following.