Research On Motion Modeling And Heading Control Method Of Large Ships

While large ships sail on the sea surface, a lot of disturbance of environment like sea winds, sea waves and sea currents act on them, which bring disadvantageous influence to the equipment on ships, the carrier planes taking off and landing, suitability of staff, navigability, security and so on, therefore, the research on large ships maneuverability in winds, waves and currents appears especially important. The establishment of ships dynamic model and the design of ships movement controller are both the most important research questions of the ships motion control. Based on the movement characteristic of large ships and the affect of winds, waves and currents, this thesis established the three unrestricted motion mathematical model of large ships, then accomplished the heading control simulation by choosing the appropriate controller.Firstly, this thesis established the three unrestricted motion mathematical model of large ships based on the MMG separation formula, which discussed and analyzed the hydrodynamic forces, moments and interrelationships, the large ships propeller thrust, the forces and moments of environment disturbance. Then applied the standard Runge-Kutta method to calculate the equation of maneuvering mathematical model by using Visual C++ programming language, the simulation of straight and turning movement in the still water were accomplished to confirm the motion mathematical model, also, taking into consideration of the winds, waves and currents, the simulation of the ship turning movement were accomplished. At last, designed the PID controller and accomplished the heading control simulation.The analysis of simulation results showed that, the established three unrestricted motion mathematical model of large ships was correct and practical, the designed PID heading controller had the good performance.