火星探测器同步轨道进入时间优化及控制

Optimization and Control of Mars Rover Synchronous Orbit Entry Time

为了减少火星探测器在着落过程中的失联时间,对探测器从火星同步轨道开始至悬停的相关阶段,进行了一系列数理推导和简化,以动态规划模型对其进行统一,利用欧拉法将模型中各阶段的微分方程进行初步处理与完善,提出了基于自适应遗传算法的时间优化及控制方案,最终得到失联时间最优解279 s,进入大气时的探测器速度417.4 m/s,其与探测器和质心连线的夹角86.746°.本文通过多自由度微分方程组构建探测器着陆数学模型,最终得出质量变化量及优化时间,并与着陆过程视质量不变的情况作对比,得出其精确误差为15%.上述方案符合实际着陆情况,并在安全着陆的情况下减少了探测器的失联时间.

In order to reduce the disconnection time of the Mars probe during the landing process,a series of mathematical derivation and simplification were carried out for the related stages of the probe from Mars synchronous orbit to hovering,which were unified by the dynamic programming model,and the differential equations of each stage in the model were preliminarily processed and improved by the Euler method.A time optimization and control scheme based on adaptive genetic algorithm is proposed.Finally,the optimal disconnection time is 279 s,and the included Angle between the detector velocity and the detector's centroid line is 86.746°,and the detector velocity is 417.4 m/s when entering the atmosphere.In this paper,the landing mathematical model of the probe is constructed by multi-degree-of-freedom differential equations.Finally,the mass variation and optimization time are obtained,and compared with the landing process under the condition of constant mass,the accuracy error is 15%.The above scheme conforms to the actual landing situation and reduces the lost contact time of the probe under the condition of safe landing.