基于航天器解体事件的空间碎片寿命算法

Space debris lifetime algorithm from spacecraft breakup events

研究了针对航天器解体事件所生成的空间碎片的寿命计算方法.给出了基于NASA标准航天器解体模型的航天器解体算法.该算法生成的一系列碎片参数,将作为寿命计算的初始条件.总结了现有求解碎片寿命的算法,并提出了一种半分析算法.该算法运用平均根数法的思路,计算了在J2摄动项的影响下,碎片的半长轴和偏心率的变化率;并采用微分积分法预报半长轴和偏心率随时间的变化.为了适应时变大气模型,该算法限制了计算步长.通过与数值法的比较分析了算法的计算速度和精度.选用了3种大气模型:SA76、GOST和MSIS-00,分析了不同大气模型在计算碎片寿命之间的差异.通过与P-78卫星解体事件的实测数据对比验证了整个算法的正确性.

A method to calculate lifetime of debris generated from spacecraft breakup events was presented. Based on NASA standard spacecraft breakup model, a spacecraft breakup algorithm was given, which yields a set of parameters of produced fragments that can serve as input for lifetime calculation. Current space debris lifetime algorithms were summarized and a semi-analytical algorithm was developed. By means of mean element method, rate of change of semimajor axis and eccentricity of fragment were calculated, in which J2 short-period variation was considered. Differentiation-integration method was applied to propagate the semimajor axis and eccentricity forward into time. Besides, calculation step of the algorithm was constrained to cooperate with time-varying atmosphere model. The computational speed and accuracy of the lifetime algorithm was analyzed through comparisons with a numerical orbital propagator. In order to find a suitable atmosphere model for lifetime calculation, three typical atmosphere models： SA76, GOST and MSIS-00 were compared. Finally, P-78 satellite breakup event was applied to test the whole algorithm.