Design And Optimization Of Interception Orbit In Space Warfare

With the progress of aerospace technology, battle field as well as military activities and state security has been extended into space rapidly. As a result, the form of modern war is changed. The modern hi-tech local war has been stretched into multi- dimensional space which includes the land, sea, air, outer space and electron. The entering, using and controlling of space have become the main aim of national security and developing strategy of the major military countries. In the future, the war will probably start by military spacecraft in space, so space combat will become an important attack mode.Under this background, spacecraft optimal interception orbit design method within space war is systemically studied in this paper. Firstly, the movement theory, methods of spacecraft, and celestial body are introduced. Then the position and time reference frame used in computing are given. In addition, several methods of spacecraft interception are presented; the theory and math models of every interception are constituted. Detailed movement models, examples analysis of twi-impulse minimum energy coplanar interception, and minimum energy non-coplanar interception are also selectively given when spacecraft is moving in circle orbit. Secondly, in the inertial coordinate system, the relative motion for the spacecraft to objective is described, which origin is the center of mass of objective spacecraft. According to Pontryagin principle of minimum, the limited-thrust interception optimum control equation is founded. Meanwhile, relative motion limited-thrust minimum time control equation is given. As the coefficients of equation set are variable, it is difficult to solve non-linear two points boundary value. In this paper, through simplifying model based optimum control principle, limited-thrust interception optimum control problem is transformed to double-integral integrated time and energy optimum control problem, then optimum control trajectory is given. Finally, the orbital elements are introduced as state variables and the accelerations are produced by equation as control variables, the space interception model is established. Based on the transformation of Guass-Lagrange equation, the orbital elements method on space interception is derived through the Pontryagin maximum principle. The analytic solution for solving the state variables and the control variables are gained in the end of this paper.The research shows that the kinetics interception couldn't get analytic solution for original model but the analytic solution for simplified model. When complicated space interception optimum control equation is solved, it is easier to establish interception mode by introducing orbital elements as state variables than introducing position,speed vector as state variables.