Concise nonlinear adaptive robust control of ship steering systems

For ship steering systems with the nonlinear uncertain parameters, a concise nonlinear adaptive robust control (CNARC) derived from the backstepping design method is constructed with the close-loop gain shaping algorithm (CGSA) via aid of the adaptive strategy in this paper. To overcome the high conservative of the nonlinear robust control scheme, which makes no use of the feedback information of the system, the adaptive nonlinearities compensator is introduced during the controller design. Through the analysis and the simulations, it is illustrated that the controller designed by CNARC can improve the ship steering control performance, and the robust stabilization of the controller is guaranteed. The control scheme proposed is simplification of the typical adaptive Backstepping method, therefore it has a definite physical meaning supporting the design procedure simple and direct, and it is so easy to reach information symmetric that its application would be wide.