最优气动力辅助空间拦截和交会

航天器从高轨道向位于低地球圆轨道的靶目标实施拦截或进行交会，并用间接求解的直接伴随方法，即用D型拉格朗日方法求解其优化问题。拦截条件是指在最终时刻两者的位置相同，而交会条件是指不仅位置相同且最终的速度矢量亦相等。文章讨论了最小时间与最小脱靶量，或最小时问与最小燃料消耗的复合性能指标，以及推力协同机动的优化解。推力协同下，对于特定情况，如在热流约束边界部分推力弧是奇异的，气动力控制是正常的。这种复杂性和奇异问题的求解在拦截和交会问题中都是值得慎重处理的。

Optimal Aeroassisted Orbital Interception and Rendezvous

Optimal trajectories are obtained by using a direct adjoining approach (so called the D form Lagrangian)for the interception or the rendezvous of a target in low circular Earth orbit by a vehicle which is initially in a high orbit. The interception condition is that the attack vehicle has the same position as the target at final time, but the rendezvous condition is that both vehicles have same position and same velocity vector at final time. In this paper, a minimum linear combination of target-escape, or fuel-consumption and flight time as the performance index, and the thrust programming in aeroassisted maneuvers are considered, which will lead to a singular thrust arc over the heating rate boundary in optimal control problem for the special case in which the thrust is singular while the aerodynamic controls are regular. These results show that the complexities introduced by the synergetic maneuver with thrust programming and the necessity to find the solutions in the optimal aeroassisted orbit interception and rendezvous should be carefully treated.