Nonlinear Observer-Based Control of an Under-Actuated Hovercraft Vehicle

Abstract This paper presents a model-based approach to the nonlinear tracking control for the body-fixed velocities of an under-actuated hovercraft vehicle. To enable a corresponding state feedback with accurate velocity signals, an observer-based sensor fusion is envisaged using acceleration measurements as well as data from an optical flux sensor. The horizontal and the vertical motion of the vehicle are modeled accordingly, and decentralized state-space representations are used for a subsequent nonlinear control design, where flatness-based techniques are employed for simplicity. To ensure steady-state accuracy, integral parts are introduced in the stabilizing feedback laws. The performance of the proposed control structure is investigated by simulation using an identified model of a corresponding experimental vehicle. In addition, also first experimental results are provided.