Application of Active Disturbance Rejection Control in ship course and track control

Active Disturbance Rejection Control (ADRC) technique is proved to be very effective because it does not entirely depend on mathematical model of the plant and it can compensate the internal and external disturbances dynamically. This paper investigates the applications of ADRC in ship motion control and presents the design method of ADRC controller appropriate for both ship course control and ship track control. Firstly, with respect to the nonlinear ship course model, a linear ADRC controller is designed by using a third order extended state observer (ESO) inside ADRC, where a systematic Matlab Simulink diagram procedure is proposed. Simulation results demonstrate that ADRC has a good disturbance reject ability for ship course tracking and keeping. Secondly, with an elegant transformation, the proposed ADRC scheme is directly applicable to ship track control design. The simulation results indicate that the controller designed can achieve a good tracking performance.