末端能量管理段迭代校正轨道算法研究

针对航天器进入末端能量管理段接口处时位置和航迹偏角存在大范围摄动的问题，提出一种使用迭代校正法的轨道快速生成算法。该算法可以根据航天器的具体初始状态，自动选择直接进场或者间接进场策略，快速生成可行的参考轨迹。首先通过跟踪轨迹地面投影实现侧向制导；根据末端能量管理段的起始点与终点的高度与速度约束生成参考动压-高度剖面，并跟踪此剖面实现纵向制导。然后采用迭代校正计算快速确定航向校准柱的位置与最终半径两个参数用以调整航程，保证航天器在末端的所有状态满足自动着陆段接口的边界约束。仿真结果校验了该算法可以根据航天器的具体状态快速生成符合约束条件的末端能量管理段飞行轨道，具有很好的鲁棒控制性能。

Research on Terminal Area Energy Management of Orbit Algorithm with Iterative Correction

 Aiming at the problem of the large perturbation in the initial position and azimuth angle for a spacecraft reaching the terminal area energy management (TAEM) interface, a new TAEM orbit algorithm based on iterative correction is designed. First of all, the ground track is used in the algorithm to piece the lateral guidance law and track the dynamic pressure-altitude profile which is generated based on the altitude and velocity constraints of the initial and ending point of TEAM to design the longitudinal guidance law. Secondly, the iterative correction is used in the algorithm to determine the position of the heading alignment cylinder (HAC). At last, the trajectory can be adjusted rapidly its final radius until the required conditions for approach and landing interface are met. The simulation results demonstrate that the TAEM orbit algorithm based on iterative correction calculates the referenced trajectory rapidly by the spacecraft’s states and the request of landing is satisfied by the control function.