The Design And Optimization Of Fuzzy PID Autopilot

With the development of technology,the control systems within the theory and application in industry access to mature.More and more intelligent control algorithms emerge as the times require.However,the application is always along with the theory,which makes the traditional PID control is still the mainstream.The modern autopilots design within PID control,while with the improvement of ship automation and the navigation environment and hydrological conditions changeable,the ship control becomes difficult to achieve.In this paper,a fuzzy controller is designed based on fuzzy mathematics theory and logic theory to realize the control of ship course keeping.In addition,an adaptive fuzzy-PID controller is designed by combining the advantages of fuzzy control and PID control.By analyzing the mathematical expression of fuzzy controller,a more simple and effective fuzzy-PID autopilot is designed.The new Ship Autopilot has better stability,small overshoot,and fast response.In general,the quantization factor and scale factor of fuzzy controller are set to a constant based on experience,which makes it blind and Inaccurate.Because the fu.zzy controller itself has fuzzy processing and online adjustment function,according to the conventional fuzzy-PID controller on-line real-time adjustment of PID parameters,this paper designs the fuzzy controller to modify the quantization factor and scale factor of the new fuzzy-PID controller,which makes the controller better.In this paper,performance analysis of the fuzzy logic controller and conventional fuzzy-PID controller and new fuzzy-PID controller has been done by the use of Matlab and Simulink.Ship model is based on the second-order Nomoto ship motion and the steering model is controlled by two-way analog control of the steering servo system.Simulation shows high effectiveness of the new fuzzy-PID controller based on fuzzy controller in comparison with the new fuzzy-PID controller.