Safety-Guaranteed, Robust, Nonlinear, Path-Following Control of the Underactuated Hovercraft Based on FTESO

On account of the external disturbances and difficult maneuverability a hovercraft, this paper devises safety-guaranteed, robust, nonlinear, path-following control strategy hovercraft targeted for unknown dynamics, unavailable velocity, ocean disturbances. Firstly, sake accurately observing lumped velocity measurements, finite-time extended state observer (FTESO) is proposed. Secondly, line-of-sight (LOS) guidance law constructed with bounded-gain-forgetting (BGF) adaptive estimator devised to follow desired path while considering environmental accurately, in which tracking errors parameter estimation are both proven be bounded. In addition, safety, safety-guaranteed auxiliary system that can constrain drift angle during hovercraft’s navigation Thirdly, controllers achieved high performance compensation backstepping method. Finally, according Lyapunov homogeneous theories, observation error guaranteed zero converge an arbitrarily small region near finite time. Numerical simulations illustrate effectiveness proposed scheme.