Research on trajectory tracking control of cascade MPC based on ship kinematics and dynamics

Objectives For the problem of three-degree-of-freedom full drive ship trajectory tracking, this paper presents a cascade MPC control algorithm to design the controller and realize ship trajectory tracking control. Methods Firstly, the MPC controller is designed by combining the ship kinematics equation and ship dynamics equation respectively, and then combined together to form a cascaded MPC model prediction controller. Then, an optimization solution problem with state variables, input variables and final value variables as objective functions was constructed. Considering system input and state constraints, a CyberShip II fully driven ship was simulated to verify the circular trajectory under environmental interference force, and the influence of parameters of the cascaded MPC controller was analyzed. Finally, the influence of controller parameters on circular trajectory tracking performance is studied under the interference of environmental forces with different frequencies and amplitudes. Results The designed controller can effectively meet the performance requirements of trajectory tracking, and can resist different degrees of environmental interference by adjusting specific parameters, which improves the robustness and stability of the system. Conclusions The research results provide a certain reference value for the trajectory tracking of fully driven ships.