摘要
在再入轨迹优化中考虑了不确定性因素的影响,并根据鲁棒优化理念,构建了再入飞行轨迹鲁棒优化模型。轨迹鲁棒优化模型中包含随机变量,现有轨迹优化方法难以求解;针对此困难,采用协方差分析描述函数法(CADET)将含有随机变量的轨迹鲁棒优化模型转化为等价的确定性轨迹优化模型,然后用伪谱法求解。以考虑气动参数不确定性的再入轨迹优化问题为例,分别用确定性优化和同时约束均值与标准差的鲁棒优化方法进行求解。结果显示,相较于确定性优化,鲁棒轨迹优化得到的最优再入轨迹对于气动不确定性的敏感度明显降低,表明了本研究提出方法的有效性。
Uncertainties are taken into account in reentry trajectory optimization and a robust trajectory optimization model is constructed based on the robust optimization theory.There are computational difficulties in solving this robust trajectory optimization problem due to the random variables associated with the uncertainties.To overcome these difficulties,the covariance analysis describing function technique(CADET)is employed to convert the robust trajectory optimization model into an equivalent deterministic trajectory optimization formulation,which is then solvable by using the existing pseudo-spectral method.In the case study,a robust reentry trajectory optimization problem considering the uncertainties of aerodynamic parameters is solved to obtain the robust optimal trajectories.By comparing with the traditional deterministic optimal trajectories,the robust optimal trajectories are significantly less sensitive to the uncertainties of aerodynamic parameters,showing the effectiveness of the presented method.
作者
刘旭
李响
张后军
郭宇恒
王晓鹏
LIU Xu;LI Xiang;ZHANG Hou-jun;GUO Yu-heng;WANG Xiao-peng(School of Aerospace Engineering,Beijing Institute of Technology,Beijing 100081,China;Beijing Research Institute of Mechanical&Electrical Technology,Beijing 100083,China;Shanghai Electro-Mechanical Engineering Institute,Shanghai 200233,China)
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2021年第11期1404-1415,共12页
Journal of Astronautics
基金
航空科学基金(51872003)。
关键词
再入轨迹优化
鲁棒优化
不确定性传播
协方差分析
描述函数
Reentry trajectory optimization
Robust optimization
Uncertainty propagation
Covariance analysis
Describing function