| Through analyzing the development and present status of submarine autopilot, the dissertation determines the research emphasis and framework firstly. Then, a design motion model fitted for the control system design was derived by reasonable simplification of standard submarine 6-DOF motion model. Based on the simplified motion model, the fuzzy autopilot control system is designed. Finally, the simulations of regulation control and trace control are carried out respectively. The simulations illustrate that the fuzzy autopilot control system has good control effect and fast response and small static error, if the parameters are adjusted properly.The fuzzy autopilot control system is implemented easily, but the control effect will decrease greatly when the environment conditions are changed. So we have to adopt other methods to improve the performance of the fuzzy autopilot control system. In the dissertation, the genetic algorithm is employed to combine with fuzzy control to design and implement the autopilot control system. The GA is used to optimize the parameters of fuzzy control system. The following simulations show that the fuzzy autopilot control system optimized by GA has higher control accuracy, better robustness and resistant disturbance capability.In the last chapter, the submarine motion tendencies under first order and second order wave force actions are illustrated through theory analysis and simulations, which established the foundation for studying the design of autopilot control system under wave force disturbances. When submarine curves close the water surface, the course is affected by the quasi white noise disturbances. The close water control structure is same with that in deep water. The simulations show that the control effects are close to the ideal situations. Because the first order and second order wave forces affect the deep control greatly, the close water deep controller is redesigned. The new controller has steady and credible control action on the deep control close water.Key Words: Submarine autopilot,fuzzy control,GA,submarine motion model,simulation... |
