Research On Motion Control Of A Manned Underwater Vehicle Model Based On Fuzzy PID Control

With the development of world economy, the competition for marine resources isbecoming increasingly fierce. As one of the largest marine countries, China should extend toopen sea and deep sea for the development of marine industry and marine economy. Theexploration of deep sea, similarly to that of outer space, is full of attraction and challenge inscience and technology. Therefore, there is a demand for deep-sea space station to providetechnical support and services. The normal operation of deep-sea space operation depends onmanned underwater vehicle to complete required personnel and material transportation. Asthe function of manned underwater vehicle is similar to that of deep submergence rescuevehicle, which will complete the docking task in deep sea, it has to have good ability to hover.Using the ultra-short baseline for acoustic positioning, this paper chooses the model of somemanned underwater vehicle as the study object mainly to study the motion control problem.Combined with the force analysis of manned underwater vehicle, the space motionequations in six degrees of freedom are established according to Newton Second Law andEuler motion equations. The transfer functions of heading angle and depth are obtained byusing the plane assumption theory, model decoupling and linearization to simplify theequations. Then the two dimensional fuzzy control theories are brought in to realizeparameters on-line tuning of the classical PID controller. This paper uses the Fuzzy Logicmodule of MATLAB to complete the design of fuzzy control rules and utilize the Simulinkmodule to realize the simulations of heading and depth control. The simulation results showthat Fuzzy PID control has better adaptability and robustness than PID control.The control system of manned underwater vehicle model can be divided into upperinterface control system and lower control system according to design requirements. Theupper interface control system focus on the design of the man-machine exchange interface inVisual C++environment. The design of lower control system includes creating the boot fileBootrom, building the image files of Vxworks and the specific programming design toachieve the functions of various boards. After program debugging between upper and lower,carry out the underwater experiment. The result is satisfactory and shows that the fuzzy PID control is suit for the complex motion control of manned underwater vehicle. Meanwhile theunderwater vehicle enjoys better mobility and flexibility.