Optimal course handling control for nonlinear ship maneuvering systems

[[abstract]]Under the control constraint of rudder angle, an on-line optimal course handling control with a quadratic performance index is developed in this paper for the nonlinear continuous-time ship maneuvering systems with wave disturbances. The ship maneuvering systems are represented by a linear sequential model which is derived by using the orthogonal functions. This approach permits the linear feedback control law to be applied to the nonlinear continuous-time ship maneuvering systems. The proposed optimal controller can accommodate the effects caused by wave disturbances. The on-line optimal course-keeping handling control, course-tracking handling control and course-changing handling control for a ship maneuvering system with wave disturbance are pre-sented to illustrate the considerable promise that the proposed method exhibits