基于气动辅助变轨的变气动外形飞行器概念研究--最优控制律问题

从一个天地往返飞行器的上升轨道和再入返回轨道的优化，以及适用不同飞行任务的变轨要求的气动外形问题，提出一项基于气动力辅助变轨的变气动外形飞行器的新概念研究。对于一个固定气动外形飞行器要同时满足上升轨道有效载荷最大和再入轨道热流峰值、过载峰值及机动性能约束下的成本最低往往是困难的。若同时满足不同飞行任务：飞往太空站的运输任务，空间拦截和交会机动巡航任务及星际探测任务，则更为困难，实际上是不可能的。文章研究基于气动力辅助变轨，在热流约束下，气动外形参数变化对最优控制的影响。其结论为：热流约束下的最优控制解，包括考虑推力协同变轨，除了在非约束弧的滚转角不直接受气动外形影响外，其余的控制律，升力系数和滚转角都是气动外形参数和攻角的函数。因而变气动外形可作为一项新技术，即通过气动外形参数变化和相应的变轨策略而获得性能和成本都最佳的用途很广的一种新型飞行器。

New concept of variable aerodynamic shape spacecrafts based on aeroassisted orbital transfer--Optimal control problem with heating-rate constraint

In this paper a new concept of variable aerodynamic shape vehicle based on aeroassisted orbital transfer is suggested,according to satisfy the different requirements of aerodynamic performace in ascent and decent trajectory,and optimal orbital transfer for different flights,for example,space transportation flight to space station,cruise maneuver of space interception and rendezvous, planetary mission etc.Even in reentry flight,the different spacecraft configuration has the different optimal control strategy with the constraints on heat rate,the acceleration in axis direction of spacecraft and the manoeuvrability for orbital plane chang.However,in view of the optimal design,it is impossible for a spacecraft with a fixed aerodynamic shape that the multiobjective requirements for various flights can be satisfied.The results demonstrate that the optimal control laws with heating rate constraint are the functions of aerodynamic shape paraments and the angle of attack,except the bank angle along unconstrained arcs.This results indicates that the low cost and the high performance gains of a spacecraft suited different flight missions can be obtained by varying its aerodynamic shape.