Since complex controllers do not suit for application,we design a simple controller with robustness in changeable sea state.The characteristics of ship motion are large inertia,strong nonlinearity and large time delay.This paper employs adaptive sliding mode technique.We focus on a class of underactuated ship systems with parametric uncertainties and wave efects.Random wave efects are seldom considered in former studies.Various simulations validate the adaptive characteristics and robustness of the proposed controller.The closed-loop system is stable and tracking error can be arbitrarily small by Lyapunov approach.
Since complex controllers do not suit for application,we design a simple controller with robustness in changeable sea state.The characteristics of ship motion are large inertia,strong nonlinearity and large time delay.This paper employs adaptive sliding mode technique.We focus on a class of underactuated ship systems with parametric uncertainties and wave efects.Random wave efects are seldom considered in former studies.Various simulations validate the adaptive characteristics and robustness of the proposed controller.The closed-loop system is stable and tracking error can be arbitrarily small by Lyapunov approach.