Effects of Self-Shadowing on Nonconservative Force Modeling for Mars-Orbiting Spacecraft
Effects of Self-Shadowing on Nonconservative Force Modeling for Mars-Orbiting Spacecraft
复制标题
自遮蔽对火星轨道航天器非保守力建模的影响
DOI：
10.2514/1.41679
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
David E. Smith
中科院分区：
文献类型：
--
作者：
E. Mazarico;M. Zuber;F. LeMoine;David E. Smith
本文对影响火星轨道航天器的非保守力模型进行了改进。最近的高分辨率重力场能够恢复无线电跟踪数据中的较小信号，这些信号以前被错误建模的重力异常所掩盖。特别是，新的力模型对航天器所受的大气阻力的估算有很大的帮助。考虑到航天器物理模型的板间自阴影，可以更精确地计算进入大气阻力和太阳直接辐射压力方程的航天器横截面面积。相关的表面面积平均可以变化20%左右，并且在一个轨道（10%）内变化很大。这些更新的模型的好处进行了评估与两个航天器，火星奥德赛号和火星侦察轨道飞行器。非保守力的变化会对重建的航天器轨道产生显著影响，估计的模型参数依赖于航天器的几何形状和轨道。火星奥德赛估计的大气密度与太阳辐射的自遮蔽有很大的改善，但在火星侦察轨道器的情况下，阻力和太阳辐射的改善都很重要。
Modeling improvements of nonconservative forces affecting Mars-orbiting spacecraft are presented in this study. Recent high-resolution gravity fields enable the recovery of smaller signals in the radio tracking data, previously obscured by mismodeled gravitational anomalies. In particular, the estimation of the atmospheric drag experienced bythespacecraftbenefitsfromthenewforcemodels.Moreprecisecalculationsofthespacecraftcross-sectionalareas enteringtheequationsfortheatmosphericdraganddirectsolarradiationpressurearepossiblebyaccountingforthe interplateself-shadowingofthespacecraftphysicalmodel.Therelevantsurfaceareascanchangebyasmuchas20% on average, and the effects can be very variable within one orbit (10%). The benefits of these updated models are assessed with two spacecraft, the Mars Odyssey and the Mars Reconnaissance Orbiter. The changes in the nonconservative forces can significantly impact the reconstructed spacecraft trajectory and the estimated model parametersdependonthespacecraftgeometryandorbit.TheatmosphericdensityestimatedbytheMarsOdysseyis much improved with self-shadowing applied to the solar radiation, but improvements to both the drag force and the solar radiation are important in this case of the Mars Reconnaissance Orbiter.