探月返回器跳跃式再入过载抑制算法研究

针对小升阻比探月返回器大航程、跳跃式再入的特点，采用了新的过载约束条件，并在此基础上对过载抑制问题进行了描述。然后对跳跃式再入过程中影响开普勒段航程的因素进行了分析，将气动升力在地球矢径方向的分量等效为万有引力的小扰动力，推导得出了与预测校正制导律相结合的过载抑制算法。最后通过仿真校验了该算法在不影响返回器着陆精度的前提下有效实现了过载抑制，各种偏差情况下的蒙特卡洛仿真也体现了该算法的实用性及鲁棒性。

Research on Load Relief Method for Skip Reentry of a Lunar Return Vehicle

The new overload constraint is  used for a lunar return vehicle with low lift to drag ratio in the skip and  long range reentry, on this basis the load relief problem is described. Based on the analysis of the factors affecting the Kepler phase flight range in the skip reentry trajectory, the component of the aerodynamic lift in the direction of the radius vector of the Earth is equivalent to small perturbation force of the universal gravitation, and an effective overload relief method combined with the corrector predictor guidance law is derived. The simulation demonstrates that the algorithm can restrain the overload effectively without affecting the landing accuracy. The Monte Carlo Simulation results for dispersed cases show the practicability and robustness of the algorithm.