交会对接任务碰撞规避策略制定研究简

针对交会对接任务目标飞行器与追踪器轨道运行特性,综合考虑规避策略计算方法与工程实际相结合的问题,提出高度规避、时间规避以及与正常轨控相结合的碰撞规避策略计算方法等三种空间目标碰撞规避策略计算方法.高度规避计算方法采用了Lambert飞行原理,用简化二体开普勒模型取代高精度轨道预报方法,迭代求解规避机动速度增量,实现了通过约束过交点与目标径向距离差得到速度增量的最优解;时间规避计算方法通过轨道周期与速度增量的关系,实现了通过约束过交点与目标的时间差得到速度增量的最优解;与正常轨控相结合的碰撞规避策略计算方法,在正常控制考虑冗余控制量的基础上,对控制策略的控制开始时间或沿迹方向的速度增量进行较小的修正,使两者通过碰撞点的时刻或径向距离错开,达到碰撞规避的目的,该方法不仅可以节省燃料、而且对任务的影响较小.通过对三种空间目标碰撞规避策略计算方法仿真分析结果表明,完全适用于交会对接任务,可为我国载人航天任务飞行安全提供技术保障.

Research on Avoidance Strategy for Rendezvous and Docking Mission

Considering the characteristics of orbital motion of the target vehicle and the tracking spacecraft in the rendezvous and docking mission, three kinds of space object collision avoidance strategy calculation methods were proposed according to the engineering practice, including height avoidance method, time avoidance method and combination with normal orbit control method. Height avoidance calculation method was based on the principle of Lambert flight. A simplified two-body kepler＇s equation was used instead of the high precision orbit prediction method. Avoidance maneuver velocity increment was solved by iterating and the optimal solution of the velocity increment could he obtained by constraining the radial distance difference between the intersection point of target and space debris. Time avoidance calculation method was based on the relationship between velocity increment and orbital period and the optimal solution of the velocity increment could be obtained by constraining the time difference between the intersection point of target and space debris. The combination with normal orbit control method was based on the redundancy control in the normal control. A small modification to the control time point or a- long-track velocity increment in control strategy could realize collision avoidance by staggering the collision point or radial distance. It not only saves fuel, but also has little effect on the mis- sion. The simulation analysis of the three methods showed that all the three methods were suit-able for the rendezvous and docking mission and could provide technical support for the safety of China＇s manned space flight missions.