Research On Ship Track Control Based On Active Disturbance Rejection Control

70%of the area of the Earth is covered by ocean, the ocean contains a lot of natural resources, with the increasing activities of human in marine engineering,there is an increasing demand for the controlling of ship posture and tracking. The performance of the controller is the key dynamic positioning vessel track control. ADRC (Active Disturbance Rejection Control) technique is a control method that combined of PID control with modern control theory. It is a way to resist external disturbance which does not rely on accurate mathematical model and has high control accuracy and robustness, is suitable for ship motion control which contains strong disturbance, nonlinear, large inertia and delay. Thus, this paper is researching on ship tracking control problem which is based on ADRC technology and use three-dimensional simulation technology to display.First, based on the equations of dynamics and kinematics of rigid bodies, established a simplified linear ship motion control equations and the normal disturbance model such as wind, wave and current. Compared to the identification ship model, verifying the correctness and accuracy of the simplified model in low-speed motion.Secondly, the study of LADRC (linear Active Disturbance Rejection Control) algorithms and tracking control strategy. Discussed of the structure and principle of three parts in ADRC, the tracking differentiator, the nonlinear error feedback and the ESO (Extended State Observer). According to the structure of the ship motion model, we analysis of the second-order ADRC and third-order ESO algorithm. Design a LADRC that solves the problem which the parameters and stability of ADRC is hard to setting and proving, using the method of three-ω for setting the parameters of LADRC is easier. Using transition process in ADRC, the ship’s outputs can be follow the system’s inputs well, so the derivative of the ship outputs is approximately equal to the derivative, thus achieving that both ship motion and ship speed can be controlled. Analyzed the ADRC control outputs by using MATLAB/Simulink, identified the control result of ADRC.Finally, based on the Unity3D engine, designed3D ship tracking control program and GUI interface, it makes the simulation more visualized. In Unity3D, use C#language to programming the ship model, ADRC controller and GUI interface, it also means the ADRC algorithms is suit for computer control and easy to program.