地火转移轨道误差分析与第1次中途修正计算

针对地火转移过程中出现的各种误差,基于地火转移轨道的误差传递矩阵分析误差发散的性质,在此基础上讨论如何选取轨道中途修正的时机,并基于该矩阵对地火转移轨道第一次中途轨道修正的速度增量进行估算.与微分修正方法的严格计算结果的比较表明,基于该方法定性研究地火转移轨道第1次中途修正速度增量变化和选取合适的轨道机动时机是可行的.使用蒙特卡洛数值模拟对上述方法和微分修正方法进行计算和比较,结果表明,第1次中途修正速度增量大小差异不超过1.2 m/s,相对误差不超过6％.在轨道控制精度大约为1 m/s的情况下使用该方法代替微分修正方法进行计算,可以节省大量的计算时间.

Analysis of Error Propagation and Computation the First TCM of the Transfer Orbit to the Mars

Propagation of different kinds of errors in earth-Mars flight is analyzed based on the error transition matrix.On the basis of this,the timing and velocity increment for TCMs(Trajectory Correction Maneuver) to eliminate specific errors are calculated.Comparison of the result with the result got through differential correction method shows that it is feasible to estimate the time and velocity increment of TCMs.Monte Carlo simulation method is employed to compute the first TCM using differential correction method and the one put forward in this paper.The result shows that the deviation of velocity increment of the first TCM is less than 1.2 m/s and the relative error is less than 6%.Therefore,it is reasonable to replace the differential correction method with the proposed method when orbit control precision is around 1m/s,and it saves significant computation time.