AI 中文总结
该研究提出开源Python框架GravDyn，整合三种引力建模方法，可高效计算非规则天体的引力势与加速度，适用于小天体相关的航天任务设计与轨道研究。
AI 中文摘要
GravDyn是一款用于计算非规则天体周围引力势与加速度的开源Python包。它在同一工作流中实现了三种方法：常数密度多面体法、基于四面体分解的分层质量集中块（mascon）近似法，以及引力势级数展开法（PSEM）。该包可处理形状模型预处理、构建所选引力表示，并高效计算引力势与加速度。三种方法适用于不同场景：多面体模型提供近表面参考解，mascon模型支持分层内部密度结构，PSEM在生成多项式系数后可在布里渊球外实现快速计算。针对多面体解的验证测试表明，mascon与PSEM模型能以较小相对误差复现参考引力势，同时降低计算成本。GravDyn旨在用于任务设计、航天器运动研究、轨道稳定性分析，以及小行星等小天体的引力建模研究。
英文摘要
GravDyn is an open-source Python package for computing gravitational potentials and accelerations around irregular celestial bodies. It implements three approaches within the same workflow: the constant-density polyhedral method, a layered mascon approximation based on tetrahedral decomposition, and the Potential Series Expansion Method (PSEM). The package handles shape-model preprocessing, builds the selected gravity representation, and evaluates potentials and accelerations efficiently. The three implemented methods serve different regimes: the polyhedral model provides a reference solution near the surface, the mascon model supports layered internal density structures, and PSEM offers fast evaluation outside the Brillouin sphere once the polynomial coefficients have been generated. Validation tests against the polyhedral solution show that the mascon and PSEM models reproduce the reference potential with small relative errors while reducing evaluation costs. GravDyn is intended for mission design and studies of spacecraft motion, orbital stability, and gravitational modeling around asteroids and other small bodies.
