Adaptive fuzzy control for ship dynamic positioning system

A fuzzy adaptive control scheme was proposed in the dynamic positioning of ships. The low frequency motion states of ship were estimated through Kalman filtering based on an approximate linear model. After the estimated values were fuzzified they were put into a fuzzy controller, while the key part of which is a self-adaptive fuzzy system. Because of the universal nonlinear mapping capability of the self-adaptive fuzzy system, the parameters of the controller can be self-tuned according to the environment. The simulations under different sea states show that the scheme is effective.