Design Of Direction Controller For Surface Vessel Based On Generalized Predictive Control Algorithm

In the development of the shipbuilding industry,the unmanned surface vessel has become the inevitable trend of the future ship development because of its full range of information,unmanned and intelligent.The technology of the unmanned ship originated from abroad.It was first used in the military field.But in recent years,with the popularity and development of the unmanned ship technology,the application of the technology of the unmanned ship in various fields has also been widespread,such as water environment monitoring,maritime traffic,emergency rescue,patrol investigation,etc.The core of the unmanned surface vehicle is its navigation controller.Its main function is to control and optimize the motion and the state of the unmanned surface vehicle,and accomplish the mission of the unmanned ship under various navigational conditions.In accordance with the planning system,the unmanned surface vehicle generate the course and the trajectory of the target by the control algorithm calculating and fitting in the system.Finally navigation controller gives the rudder control signal and speed control signal at every moment.In this dissertation,when we design the navigation controller,we consider that the speed of the unmanned ship is basically at a constant state under the same condition,so we only study and design the course controller.Before the course controller design,firstly establish the mathematical model of unmanned ship using appropriate methods,taking into account the actual situation of motion unmanned ship will be affected by the wind,wave and current,thus establishing mathematical model of wind,wave and current.According to the traditional PID controller showed weak anti-interference ability and low control accuracy in the unmanned surface vessel heading control system,the course controller is designed by the generalized predictive control algorithm in this dissertation.Firstly we establish the corresponding state space model,and then we establish course optimization controller based on Mamdani fuzzy reasoning.According to the internal model structure,we predict the output state of the future course of the system,and add the output error to the feedback correction,comparing it with the reference input value.We use Mamdani fuzzy algorithm for rolling optimization,and then we calculate the control action that should be added to the system at the current moment.Finally the whole control loop is completed.The course feedback value of heading controller is filtered by Kalman filter,and then we input feedback value to the state space model.Thus the design of the whole course predictive controller is completed,then we optimize the control instruction according to the comparison result,so as to improve the control ability of the course controller.In this dissertation,the course controller of unmanned surface vessel is designed under the condition of the disturbance of wind,wave and current.The simulation results show that compared with the traditional PID controller,the controller based on generalized predictive control algorithm has the characteristics of high control accuracy,small steady-state error and good robustness.