Research On The Guidance Law Of Near Space Interception

The main works of this dissertation are studying the problem of the guidance law of the interception missile,including the initial guidance,midcourse guidance and terminal guidance,as well as a method of predictive intercept point and a problem of kinetic kill vehicle control.Besides,it also studies on the control analysis and performance analysis with the KKV attitude control and orbit control engines working.The main contents of the dissertation as follows:(1)Research on the initial to terminal guidance law of the interception.The initial guidance law is a parabolic trajectory with it used to increase effective range of the interception.The midcourse guidance law is an optimal guidance and the performance index is maximum velocity in the requirement of falling angle.And during the terminal guidance the interception missile already captured the target.So we use proportional guidance law in terminal guidance.Besides,the accuracy of handing over initial to midcourse guidance and midcourse to terminal guidance is also studied.(2)With the problem of intercepting TBM during the midcourse,predictive interception point is studied.That is a hypersonic vehicle can be changed to a low speed vehicle so that the required overload can be decreased and it can improve the precision.(3)Research on the engine model of KKV.The ignition switching function and switching threshold of attitude control and orbit control engines are designed in terms of the interception problem.The conclusions can effectively control the switching times and reduce the on-off times and frequency.(4)In the end,suitable simulation method is chosen and the the longitudinal-plane mathematic model as well as simulation model of KKV are established.The digital simulation is carried out with the different initial conditions.The simulation results are presented demonstrating that the performance of the guidance laws and control methods of the interception missile in this thesis can satisfy the request of high accuracy and fast response.