“嫦娥三号”软着陆轨道设计与控制策略

Optimization Model of the Trajectory Design and Control Strategies for Chang’e-3’s Soft-Landing

着陆器要准确在天体表面预定区域内实现软着陆,关键是着陆轨道与控制策略的设计。本文利用开普勒定律和机械能守恒定律,求出嫦娥三号近远月点的速度大小,结果表明与基准数据误差较小。其次,以燃耗最优为指标,综合考虑题中的速度约束和落点位置约束以及着陆的安全性,建立非线性优化模型,得到燃料最优的软着陆轨道。本文基于优化控制模型,对六个阶段分别进行讨论,将模型结果与官方数据进行比对。对探月工程部门具有一定的参考意义。

The key for Lander to accurately achieve a soft-landing in the area of the object surface is the design of landing trajectory and control strategy. This article is based on Kepler’s law and the law of conservation of mechanical energy, and calculates Chang’e-3 nearly far month point velocity. The results show that with benchmark data error is small. Second, in order to burn up the optimal index for the integrated thinking of the speed problem, placement location constraints and the safety of the landing, nonlinear optimization model is set up, getting optimal soft landing orbit of the fuel. Based on the optimal control model, this paper is discussed six phases respectively, and compares the result of the model with official figures. It has certain reference significance for the lunar exploration project department.