The Study Of Automatic Rudder Control Technology Based On Fuzzy Neural Network PID

Marine transportation is the most important mode of cargo transportation in international logistics.Compared with other modes of transportation,it has the characteristics of large volume and low freight.At present,more than 70%of the total international freight volume and about 90%of China's total import and export freight volume are completed by sea vessel transportation.It can be seen that the ship transportation industry occupies a very important position in China's national economy.The device used to realize the automatic control of the ship's motion is called the ship automatic steering instrument,referred to as the automatic rudder.The generation of automatic rudder greatly reduces the labor intensity of the crew,but its performance is not only directly related to the navigation safety and economic benefits of the ship,but also related to the problem of pollution prevention.This problem has become even more pronounced,especially when large numbers of VLCCs,LNG ships and chemical vessels have emerged.Aiming at the track changes of the automatic rudder control,the three-degree-of-freedom motion equation of the ship is established by fully considering about the lateral motion,the longitudinal motion and the free motion.The ship motion model is established by finely estimating and analyzing the parameters of the equation of motion.Consider the mutual interference of flow forces and moments between them.In order to verify the performance of the established ship model,the MATLAB/SIMULINK was used for simulation experiments to verify the reliability of the model.The control theory and its principles are introduced in detail,including conventional PID control theory,fuzzy control theory,neural network theory.The above theory is used to design the ship's automatic rudder.The fuzzy control is added to the conventional PID automatic rudder to improve the three parameters of proportional,integral and differential in PID control.The neural network algorithm is used to adjust the fuzzy quantization factor and scale factor in fuzzy control.The specific design schemes of,BP neural network and fuzzy control are given.The autopilot is compared with the conventional PID autopilot and the fuzzy PID autopilot described in this paper.It is verified that the fuzzy neural PID autopilot designed in this paper has better performance and is more conducive to autopilot and implementation.