Research On Dynamics And Motion Control Of Underwater Vehicle-Manipulator System

With the continuous depletion of land resources,people began to explore new resources.The ocean contains abundant resources.Underwater vehicles is being studied as an important tool for underwater exploration.Underwater vehicles and its manipulators can complete a series of complex tasks under water,greatly improving the efficiency of underwater operations.In order to keep underwater vehicles operate accuracy when operating under water,this thesis designs a fuzzy controller based on underwater vehicles dive,forward,back and lateral movement,and verifies the controller's effectiveness through numerical simulation and underwater model test.At the same time,the neural network control method is designed to realize the motion tracking control of the manipulator of underwater vehicle-manipulator system(UVMS).This thesis describes the concept and classification of underwater vehicles in the introduction,discusses the research trends of underwater vehicles and its control algorithms,and introduces the research trends of underwater vehicle manipulators and its control algorithms.According to the structural characteristics of underwater vehicles and the actual motion conditions,underwater vehicles is subjected to a detailed analysis of the gravity,buoyancy,thrust and hydrodynamic forces of underwater vehicles,and its movement model is established to lay the foundation for the subsequent fuzzy control.Basis on the structural characteristics and motion of UVMS,its motion and dynamics model is established.Then the fuzzy control algorithm is introduced.According to the motion feature of underwater vehicles,the structure and control rules of the fuzzy controller are studied,and the fuzzy control system is established based on the system's motion control model.The fuzzy controller is designed and the control simulation experiment was conducted to verify the correctness and effectiveness of the method.Then based on the characteristics of UVMS,neural network controller is designed to realize tracking control of manipulator.In order to ensure the controller's robustness,the Lyapunov design is applied in it.In order to test the effectiveness of the designed controller,the specific parameters of the manipulator of underwater vehicles are set.The result of the software simulation verifies that the neural network control method is superior to the PD control method.Finally,build an experimental platform.In order to verify the feasibility of the fuzzy controller designed in this thesis,a model test is conducted by using ROV(Remotely Operated Vehicles)of our research group as a test object.