绕月自由返回轨道的应急自主制导算法

Autonomous Onboard Contingency Guidance for the Circumlunar Trajectory

中文关键词  自由返回轨道  自主  故障  制导

英文关键词  Circumlunar  Autonomous  Contingency Guidance  

中文摘要

      为了提高月球探测器自主运行能力，嫦娥五号飞行试验任务的飞行软件需要在出现入轨大偏差情况下，具备在轨自主应急制导策略生成与轨道重构的能力。针对此需求，本文提出了一种适用于在轨自主生成和实施的绕月自由返回轨道应急制导策略。该策略将应急制导策略自主生成问题转化为三体Lambert问题在轨自主求解问题。发展了经典三体Lambert算法，在原算法中引入Quasi-Lambert算法解决了算法边界条件问题。该算法计算量小，计算精度高，可直接瞄准再入点参数，可显著提升探测器的自主运行能力，对未来月球探测和载人登月任务有重要的应用参考价值。

英文摘要

      For improving the autonomous operation capability of the lunar probe, the flight software of the circumlunar return and entry test mission required the capability of autonomous on-board generation of the contingency targeting guidance in a large launch deviation. For this requirement, this paper proposes an autonomous on-board guidance strategy for the circumlunar trajectory. Using the pseudo-state theory, this strategy converts the circumlunar trajectory autonomous targeting guidance problem into a three-body Lambert problem, and upgrades the classical algorithm using the quasi-Lambert problem with flight path angle constraint to resolve the boundary condition constraint of the entry interface. The new algorithm has a small computation burden, is suitable for trajectory reconfiguration under large deviation, and accurately targets the entry interface state, which can significantly improve the autonomous operation and contingency response capability, and has important application reference value for future lunar exploration and manned mission to the moon.