Trajectory Tracking For Unmanned Underwater Vehicle Based On Fuzzy Neural Network

The world's demands for resources have increased with the rapid development of science,technology and economy.The ocean has received increasing attention from the whole world.The Unmanned Underwater Vehicle(UUV),as a new type of marine exploration equipment,has promoted its importance of commercial and military value gradually.Therefore,in order to ensure that the UUV can carry out various tasks,the trajectory tracking control has become a hot research topic of scientists.The main research content of this thesis focuses on the solutions for trajectory tracking control of the UUV,and the main works has been carried out as follows:Firstly,the dynamic model of the-six-degrees-of-freedom of the Unmanned Underwater Vehicles is introduced.The-five-degrees-of-freedom mathematical model of the UUV under the earth-fixed inertial frame is finally proposed,with the simplification of the model combined with the study object.Secondly,the PD control strategy is adopted to achieve the trajectory tracking control of the UUV.The fuzzy neural network is used as compensator to eliminate the static error during the tracking process.The sliding mode control theory is taken to realize the online parameter learning.The stability of the control algorithm is analyzed,and the simulation experiment is verified.Thirdly,the fuzzy neural network is used to approximate to the sliding mode control algorithm to improve the study ability.The online parameter learning is achieved which combined with the Lyapunov stability theorem and projection algorithm.The stability of the control algorithm is analyzed,and the simulation experiment is verified.Finally,the self-organizing fuzzy neural network is used to approximate to the uncertainties of the feedback linearization control method to decrease the computation load.The sliding mode controller is added to neutralize the external disturbance.The stability of the control algorithm is analyzed,and the simulation experiment is verified.Finally,the trajectory tracking of UUV has been realized successfully.