不规则小行星附着可达区生成方法

Reachable Zone Generation for Irregularly Shaped Asteroid Landing

针对不规则小行星表面附着任务需求,提出了一种基于动态邻域搜索的可达区生成方法。首先,建立了可达区数学模型,并采用质心距映射函数对非定点附着的终端位置约束进行了处理。在此基础上,将可达区的优化问题转化为附着基准点计算、边界起始点计算和边界点搜索三个子问题。针对附着基准点与边界起始点,分别通过最小燃耗轨迹优化与极限燃耗轨迹优化求解;针对边界点,设计了导向式动态邻域搜索方法,将复杂的非定点着陆优化问题简化为定点着陆燃耗优化与边界插值。最后,以小行星433 Eros为对象,对所提出的可达区生成方法进行了仿真。结果表明,该方法能够生成不规则小行星表面的可达区,具有较高的搜索求解效率,并适用于不同的初始位置和燃耗条件。

A reachable zone generation method based on the dynamic neighborhood search is developed for landing on irregularly shaped asteroids.Firstly,the reachable zone is formulated,and a centroid distance mapping function is designed to constrain the terminal position of a trajectory with an unfixed landing point.On this basis,the reachable zone generation problem is decomposed into three sub-problems:the reference point calculating,the starting point calculating,and the boundary points searching.The reference and the starting points are solved by a trajectory optimization for minimum fuel and maximum distance,respectively.The boundary points are calculated using a guided dynamic neighborhood search method,and in each search cycle,the minimum fuel is optimized with a fixed landing point.Finally,the proposed method is verified using the 433 Eros model.The results indicate that the method is effective in generating a reachable zone on an irregular surface,efficient in searching the boundary points,and applicable to various initial positions and fuel consumptions.