Research On Ground Missile Affine Nonlinear Modeling And Fuzzy PID Control

The ground missile affected by a variety of internal and external factors, those made the missile system has a large number of nonlinear, strong coupling of internal movement and flight problems such as instability. Thus increased the difficulty of the flight control. In order to make the missile can hit the target accurately and quickly, and improve the efficiency of its combat. It is very important that we establish the body with six degrees of freedom model which have a high degree of confidence and good stability,and use an excellent control algorithm to design a high performance controller. In this paper, based on the missile affine-nonlinear modeling and attitude control as the background, by using the parallel fuzzy PID algorithm as a tool, the model of controller design. Therefore, the research of ground missile dynamics model for itself flight control has distinctly important theoretical significance and practical application value.The main research of the work includes the following several major fields:1. Firstly, it needs to establish the missile’s nonlinear equations, and then by the affine processing to build the affine-nonlinear format. On the Matlab/Simulink platform build the whole simulation model which has missile subsystems model. Through compared with the STT model and validate missile model feasibility.2. It deep studied from the structure of the fuzzy controller, which introduced the PI control to design a parallel type two-dimensional structure of fuzzy PID controller.Its structure is the fuzzy PD+fuzzy PI. It analysis from two major aspects for the Control method, the one is that consider the control rules of fuzzy control how to set, the other one is that the relationship of fuzzy quantification factors between the PID controller parameters which is KP, KI, KD. Through the simulation result shown that the system which has the parallel two-dimensional structure has better performance in the aspect on the overshoot and adjustment time than single PID control and fuzzy control.3. The missile system has stronger nonlinear, mutual coupling and time varying characteristics, by using linear perturbation method gets the pitch transfer function,so it aim at the feature points which are the begin control point, the maximum velocity point, the terminal velocity point during the missile attacked the target, to design the parallel type structure of fuzzy PID controller. Using it realizes to the missile attitude stability. Given it a step signal as its input, by simulating on three points, and it analysis the frequency domain characteristics. It proves that the method can apply to the missile attitude.4. Using the Matlab/Simulink platform to construct the model of missile attack the target which joined the target module, rudder, seeker, guidance and control module.Based on the model to verify that the controller can act on missile attitude.Simulation results show that it is better than the classical PID controller and fuzzy controller in the control effect.