Nonlinear control of hydrofoil catamaran course in three DOF

High performance ships have a lot of advantages, but would cause a larger heeling than normal ships when turning in the high-speed. In this paper, we study the design method of joint controller for the hydrofoil catamaran nonlinear course in three degrees of freedom with heeling using Lyapunov´s direct method and fuzzy control method. Firstly, according to the turning characteristics, we give a simplified model in three degrees of freedom; Secondly, variable coefficient nonlinear rudder angle control law is designed based on Lyapunov´s direct method, which could enable the closed-loop system stability; Thirdly, the fuzzy control rule was designed according to the characteristics of ship´s heeling; Then, controller is optimized by using the fuzzy method; Finally, we presents a simulation of the nonlinear model in four degrees of freedom, and the result proves the effectiveness of the proposed controller.