星际探测太阳帆行星和太阳借力轨道全局优化

Global optimization of solar sail gravity assist and solar photonic assist trajectory for interstellar mission

以太阳帆在20年内飞行至距离太阳200 AU以远进行星际探测为目标,研究太阳帆通过行星借力和太阳借力的轨道全局优化问题。建立太阳帆时间最优转移轨道数学模型,分析行星借力和太阳借力的约束条件,并用这些约束条件构造目标函数,从而将轨道优化的四点边值问题转化为求解无约束条件下的多变量优化问题。通过选取合理的约束权重,采用遗传算法获得大范围的粗略解,代入到序列二次规划算法中获得高精度解。仿真结果表明,虽然太阳帆通过太阳借力已获得相当大的加速度,但加上木星借力仍然可以节省相当多的飞行时间。提出的轨道优化思路,可以为太阳系逃逸任务轨道初步设计提供参考。

With the goal of solar sail mission to near interstellar space（ 200AU） in 20 years,a global optimization problem of solar sail gravity assist and solar photonic assist trajectory for interstellar mission was studied. A mathematical model for solar sail time-optimal trajectory was established. By taking the constrains of solar sail gravity assist and solar photonic assist into the object function,the four-point boundary value problem of orbit optimization can be converted to multi-variable optimization problem of no constraint. With choosing appropriate constrain proportions,the problem was solved by using genetic algorithm and sequential quadratic programming method. Optimization result shows that plenty of time can be saved by adding Jupiter gravity assist,though solar sail gains a large velocity with solar photonic assist. The proposed global optimization algorithm will provide a reference for the preliminary design of solar system escape orbit.