Study On Control Methods For Pitching Movement Of Missile

As the current most important precision-guided weapons, missiles play a leading role in modern battlefield, thus become an important direction for the development of national military power. The increasing range and accuracy requirements and complex system architecture makes the traditional control methods unable to effectively complete the missile control tasks, many efforts have been put to the design of new missile controller to meet both speed and robustness of the current missile.Since the missile has complex motion model and a varity of uncertain factors, the main difficulty is the controller design. In this paper, to obtain a simple linear system model for controller design, linearization is performed for the short-periodic motion of small perturbations of the missile model. The application of traditional PD control in the missile pitching movement is investigated, in which the relationship between control parameters and the performance indicators of system model is established. Finally, the the performance of PD controller is validated through mathematical simulation, which shows that it can not play a satisfying perfoamance.For the problem of strong nonlinear and uncertainty of the system, a practial sliding mode controller for missile pitching movement is devised through appropriately design of the sliding surface and switching law. The saturation function is applied to eliminate chattering and ensure the quality of control system. Besides, two theorems are presented for the controller parameters selection. Simulation results show the effectiveness of the method.Consider the regulating time requirements in actual combat missions, a new algorithm which combines time optimal control and fuzzy control theory is proposed. The former can export the maximal capacity of the atuators, so that the state can be drived to the equilibrium point in a minimum time. However, the time optimal control is based on accurate mathematical model of the object, hence the system need to switch to fuzzy controllers in equilibrium neighborhood for its strong robustness. For practical engineering applications considerations, a simple non-linear function of time optimal trajectory is adopted instead of the real time optimal one, hence obtained the sub-time optimal controller. Meanwhile, based on rational design of each variable membership function and fuzzy rules, a fuzzy controller for missile pitching movement is introduced. Mathematical simulation results show that the combination them can take good use of all their respective advantages, thus a fast and accurate control effect is achieved.