Study On Approximate Vertical Diving Attack Guidance Law To Ground For Airborne Missile

As the urgency of military requirement and attention of guidance weapon for countries, the development of air-to-land missile guidance weapon has actual significance for military force. Miss distance, fuel consumption and engineering complexity are the important basis for missile design. To achieve best damage effect of the warhead of missiles, missiles are expected to obtain not only a minimum miss distance but also a particular terminal angle. At present, most of the designed guidance laws with terminal angle constraint can not satisfy military mission. Therefor, it is extremely necessary to research the guidance laws with special guidance requirement. On this occasion, the guidance laws with terminal angle constraint were researched in this paper.The main work of this thesis can be summarized as follows:Firstly, the mathematical model of the airborne missile was established. Four kinds of coordinates, the transformation of relations between coordinates, the mathe equations of the airborne missile’s dynamics and kinematics were given, three-dimensional relative motion for missile and target was established, and these work have laid foundation for the following research.Secondly, a kind of proportional navigation guidance law with over gravity compensation was designed to ensure impact angle of airborne missile.Three-dimensinal relative motion for missile and target was simplified two-dimensinal motion model in the pitch plane.On the basis of the traditional proportional guidance law, over gravity compensation was introduced to the command guidance loop, the simulink model of missile was established. The influence of initial conditions and over gravity compensation were analyzed.Thirdly, optimal vertical diving attack guidance law with position and impact angle constraints for airborne missile was proposed. The relative motion model and linear model for missile and target was given in the pitch plane. A objective function based on acceleration and time-to-go was proposed, and optimal guidance law was derived. The engineering application of trajectory shaping guidance law was tranformed based on small angle assumption. Acceleration comman was analyzed by Cauchy-Schwarz inequality.Finaly, variable structure guidance law with vertical diving attacking was investigated. In order to reduce control difficulty, the relationship between terminal impact angle and sight angle was established. Sliding model variable structure guidance law was proposed based on variable structure theory. The effect of the guidance law parameters was analyzed, which is propitious to parameter selection.In the dissertation, simulations were established for there guidance laws. The results proved the performance of miss distance and terminal impact angle constrains.