Study Of Ballistic-Glide Missile Reentry Trajectory Optimization And Online Re-Aiming Technology

With the innovation of military technology and the upgrading of weapons systems, there are a lot of old ballistic missiles that will be decommissioned. How to deal with these ballistic missiles and to save the country's resources is an important issue need to address. Refer to the conception of Boost-Glide Missile, those ballistic missiles can be used as a booster for the glide missile with a certain transformations, which is a solution to the issue. But the feasibility of such a solution requires a certain theoretical Analysis and simulation. Also associated with the development of missile defense systems and camouflage technology, when the glider lost its target (camouflage or hard to strike), how to select a new target, plan the optimal trajectory and tracking it are also need to address.Difficulties in the first issue focused on that glide warhead reentry with a large trajectory angle as the ballistic missile trajectory is relatively fixed. As a result, the glide must adjust its trajectory angle to fly stably, which bring on a challenge to the guidance & control systems and the thermal protection systems of the glide missile. However, the paper will use the trajectory optimization theory to analyze the feasibility of the solution. Firstly, the paper established a simplified three degrees of freedom dynamics model and motion model in the launching coordinate. Secondly, the paper use the direct shooting method and sequential quadratic programming algorithm to optimize the reentry trajectory that include the maximum longitudinal range trajectory and the maximum transverse range trajectory, which verified the feasibility of missile combination in theory. Finally, the paper simulated the trajectory over fixed path points, which will benefit for target penetration and online re-aiming to the glide missile.Difficulties in the Second issue focused on the trajectory online program and the standard trajectory tracking, totally speaking, this is a application problem of the glide-guided algorithms. The paper established the dynamics and motion models of the glide missile using energy as the independent variable. Then, proposed the glide guidance algorithms that improved on the drag acceleration reentry guidance. At last, the paper designed tow kinds of programs for online re-aiming using the glide guidance algorithms and completed the simulation analysis. The results of the simulation show that the algorithm can achieve online re-aiming of the glide missile.In summary, the paper successfully completed the research and analytical work of the two issues, but there are still some shortcomings. Firstly, the innovative theory is needed for the optimal problem of trajectory over fixed path points, so that the constraints could be refined in the optimization and the results of the optimization have more values. Secondly, further research and simulation are needed for the technology of online re-aiming, so that the errors in tracking standard trajectory in the early time of reentry with big trajectory angle and attack angle.