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研究在异面圆轨道ＬＥＯ－ＬＥＯ变轨过程中，气动辅助轨道转移飞行器（ＡＯＴＶ）大气内飞行的闭环最优导引律的设计问题。首先使用Ｌｏｈ常数项以及一些假设条件对ＡＯＴＶ的动力学模型变换、简化，然后以大气出口处速度取极大值作为最优条件，应用最优控制理论得到控制方程的解析形式。在仿真算例中，首先采用大气密度的指数模型进行控制器的设计和仿真，然后以此控制器分别控制ＡＯＴＶ在四种不同的大气密度中飞行。这四种大气密度取自Ｇｒｏｖｅｓ模型的四组不同纬度数据，其与标准大气密度指数模型的偏差范围为±６７％。仿真结果表明：ＡＯＴＶ进入到“未知”的四种不同的大气密度中，不但可以完成变轨任务，还可以极大地节省燃料。仿真结果证明所设计的闭环导引律正确、可行，而且能够补偿大气密度大范围的扰动。
This paper studies the design of the optimal closed-loop guidance law of the air-borne Pneumatic Aided Orbiter (AOTV) flight in the LEO-LEO orbit. First, the Loh constant term and some assumptions are used to transform and simplify the dynamic model of AOTV. Then, taking the maximum velocity at the exit of the atmosphere as the optimal condition, the optimal control theory is used to obtain the analytic form of the governing equation. In the simulation example, we first design and simulate the controller by using the exponential model of atmospheric density, and then use this controller to control AOTV to fly in four different atmospheric densities respectively. The four atmospheric densities are taken from four sets of different latitude data from the Groves model and deviate from the standard atmospheric density index model by ± 67%. The simulation results show that: AOTV into the “unknown” of four different atmospheric density, not only can complete the task of changing orbit, but also can greatly save fuel. Simulation results show that the designed closed-loop guidance law is correct and feasible, and can compensate a wide range of atmospheric density disturbance.