Research On Variable Direction Axis Variable Vector Propeller Control System Of Underwater Vehicle

Nowadays, the underwater vehicle has to do various complex tasks in both oceanexploitation and ocean engineering area. With the improvement of the technology, theunderwater vehicle needs to deal with some tasks that more and more difficult, so it meansthat the underwater vehicle must have a good maneuverability to adapt to the demand ofsubmersible. With the development of ocean exploitation and ocean engineering, the humanspay more and more attention to underwater vehicle which has the miniaturization, intelligent,high efficiency and high mobility, so the conventional propulsion system has been unable tomeet on the demand of human beings for submarine design. In order to improve themaneuverability of the underwater vehicle, the vector propulsion technology emerges as thetimes require. And the vector propulsion system is led to represent the development directionof the submersible propulsion system, which also will become the main propulsion system ofsubmersible. In this paper, VDA-VVP which has been designed for submersible as apropulsion system is based on vector propulsion technology, so it has a very importantmeaning to research on the VDA-VVP control system of the underwater vehicle.Firstly, the working principle of the VDA-VVP was researched, and then the systemcomposing project of VDA-VVP was proposed. The composing project of variable directionaxis servo control system was proposed by researching the principle of angle position control.At last, the composing of servo control system of variable direction axis was given.Secondly, the model of VDA-VVP for underwater vehicle is founded. This papercalculates the open water characteristics of VDA-VVP by adopting the open water diagram.The model of hydrodynamic coefficient and thrust coefficient for VDA-VVP were founded.By using the reasonable regress model and the data sampling of chats, the coefficients ofregress models were required by means of the least square algorithm. So we can get theregress models which can be used in engineering calculating. And then, the torque model ofvery axis was given by analyzing the progress of vector force decomposition of VDA-VVP. Atlast, the dynamics model and torque model of servo control system of VDA-VVP wasfounded, and then, the servo control system of variable direction axis was designed.Then, this paper studies the problem of intelligent coordination control for bow and sternVDA-VVP. The thrust distributed strategy of VDA-VVP was proposed to distribute and tocontrol the thrust reasonably. The maximum efficiency of VDA-VVP was realized throughthis method. And then, the fixed size recollection least-squares support vector machines was proposed to calculate the thrust parameter by aiming to the complicated calculating processand the low efficiency of characteristic equation.Finally, the intelligent pose control system of VDA-VVP for the underwater vehicle wasdesigned. Aiming to the moment characteristic of underwater autonomous, pose intelligentcontrol system is divided into three independent control systems, which include the horizontalmotion controller, the vertical motion controller and the space motion controller respectively.In the study of the horizontal motion control, considering with the control system which is inorder to realize the horizontal turning motion of the underwater vehicle and to solve theproblem of system complexity, this paper adopts backstepping model reference adaptivesliding mode control algorithm. By adding adaptive law into the backstepping sliding modecontrol, this method overcomes the effect of system complexity and uncertainty factorseffectively. In the study of the vertical motion control, considering with the strong variationfor center of gravity and center of buoyancy in the vertical motion process, in order toovercome the uncertainty of the model, to maintain the stability of the system and to keep theconsistency and dynamic characteristics better, this paper adopts fuzzy sliding mode controlalgorithm. The basic fuzzy controller is very difficult to reduce steady-state error by extendingthe fuzzy rule, so it adds the variable universe fuzzy controller. In the same rules, the universebecome small with the smaller error, it means that the rules have been increased. So, it canimprove the control precision of the system. In the study of the space motion control,considering with the system of multi-variables which has nonlinear, time variation andstrong-coupling, and it very difficult to establish the precise model. In order to solve theseproblems, this paper designs a multi-variables adaptive fuzzy sliding mode controller basedon the variable universe method, and then the pose control of underwater vehicle is realizedeffectively.