Study On Terminal Guidance Laws And Control Methods For Kinetic-Kill Vehicle

In this paper, the kinetic-kill vehicle (KKV), which intercepts tactical ballistic missile (TBM) in the high altitude, is researched. To meet the request of high accuracy and fast response, the KKV includes homing seeker, and direct lateral force control system, to kill the target kinetically. The guidance laws and control methods of the KKV is the main problem to be solved. The main work and results are described as follows:The models of trajectory-control system and attitude-control system are constructed, and then the motion model and dynamics model of the KKV are derived.The proportional navigation guidance law, the adaptive sliding-mode guidance law and the optimal sliding-mode guidance law are studied. The adaptive sliding-mode guidance law adopts an adaptive reaching-law of sliding-mode. It indicates that the reaching rate is adjusted with the relative range. When the relative range is large, the reaching rate is slow, when the relative range tends to zero, it arises rapidly to prevent the angular velocity of the line-of-sight (LOS) from diverging. This reaching-law makes the KKV have a very high accuracy. Moreover, adjusting the reaching rate adaptively can alleviate unwanted chattering effectively. An optimal guidance law based on the angular velocity of LOS is presented for intercepting a nonmaneuvering target. But it can't guarantee the angular velocity of LOS tends to zero for intercepting a maneuvering target. To overcome this shortcoming, this paper deals with integrating optimal guidance with sliding-mode guidance to obtain a new guidance method with robustness against target maneuver, good dynamic performance, energy saving property. At last, the adaptive sliding-mode guidance law is combined with the optimal sliding-mode guidance law. And the terminal guidance law that fits the KKV is confirmed.To solve the vibration problem, the theory of quasi sliding-mode control is adopted. After the dead zone is added, the attitude-control engines switch with a significant reduction. The simulation results demonstrate the effectiveness of the quasi sliding-mode control methods.In the end of this thesis, the six-degree-freedom mathematic model and simulation model of the KKV are established. And the six-degree-freedom digital simulation is carried out with the different initial conditions, for the terminal guidance stage. To analyze the accuracy, Monte-Carlo simulation results are presented demonstrating that the performance of the guidance laws and control methods of the KKV designed in this thesis can satisfy the request of high accuracy and fast response.