飞船返回舱再入飞行迎角和侧滑角估计

迎角和侧滑角是飞船返回舱再入飞行试验气动分析工作所需的重要参数.本文发展了基于弹道重建的返回舱迎角和侧滑角估计方法.首先,利用舱上测量数据和有限的地面雷达测量数据,采用极大似然法进行弹道重建,再现黑障区的弹道,同时给出整个再入过程的弹道参数;然后,利用几何关系法计算迎角和侧滑角,并进行风修正.对某飞船返回舱的飞行试验数据进行了计算和分析,结果证实了弹道重建数学模型和算法的正确性以及迎角和侧滑角估计方法的有效性.

Angle-of-attack and sideslip-angle estimation of reentry capsules of spacecraft in reentry flight

Angle-of-attack and sideslip-angle are two important parameters for the aerodynamic analysis of reentry capsules of spacecraft from flight test data. An angle-of-attack and sideslip-angle estimation method is developed based on trajectory reconstruction. At first, the maximum likelihood method is employed to reconstruct the trajectory of reentry capsule from on-board measurement data and limited radar data. The trajectory of reentry capsule in black-out area is thus made up. And the complete set of trajectory parameters is obtained at the same time. Then, the geometric method is employed to calculate the angle-of-attack and sideslip-angle of returning capsule. In the calculation, it is absolutely necessary to correct the affection of wind. The flight test data of some a reentry capsule are analyzed. The results validate the developed mathematical model and algorithm of trajectory reconstruction. It is also shown that the trajectory-reconstruction-based angle-of-attack and sideslip-angle estimation method is extremely effective.