It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly eval...It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.展开更多
A circumlunar free return orbit design model that satisfies manned lunar mission constraints is established. By combining analytical method with numerical method,a serial orbit design strategy from initial value desig...A circumlunar free return orbit design model that satisfies manned lunar mission constraints is established. By combining analytical method with numerical method,a serial orbit design strategy from initial value design to precision solution is proposed. A simulation example is given,and the conclusion indicates that the method has excellent convergence performance and precision. According to a great deal of simulation results solved by the method,the free return orbit characters such as accessible moon orbit parameters,return orbit parameters,transfer delta velocity,etc. are analyzed,which can supply references to constitute manned lunar mission orbit scheme.展开更多
针对复杂轨道机动规划与实际问题紧密耦合,建模和求解复杂的难题,提出复杂轨道机动规划本体元建模方法,设计并实现了通用软件。分析轨道机动规划特点,抽象得到任务段、停止条件、控制变量和约束组成的MSCC(Mission control segment-Stop...针对复杂轨道机动规划与实际问题紧密耦合,建模和求解复杂的难题,提出复杂轨道机动规划本体元建模方法,设计并实现了通用软件。分析轨道机动规划特点,抽象得到任务段、停止条件、控制变量和约束组成的MSCC(Mission control segment-Stop condition-Control parameter-Constraint)元模型体系,将MSCC元模型映射到软件设计,得到通用轨道机动规划软件类层次结构,采用C++语言实现了自主软件ATK.Planning,使轨道机动规划可以采用统一的方法描述和软件求解。针对快速交会和地月自由返回转移的仿真结果表明,软件仅通过人机界面配置就可以完成复杂轨道机动规划问题求解,收敛误差小于设定值,大大降低了任务设计时间。展开更多
基金supported by the National Natural Science Foundation of China (12072365)the Natural Science Foundation of Hunan Province of China (2020JJ4657)。
文摘It is important to calculate the reachable domain(RD)of the manned lunar mission to evaluate whether a lunar landing site could be reached by the spacecraft. In this paper, the RD of free return orbits is quickly evaluated and calculated via the classification and regression neural networks. An efficient databasegeneration method is developed for obtaining eight types of free return orbits and then the RD is defined by the orbit’s inclination and right ascension of ascending node(RAAN) at the perilune. A classify neural network and a regression network are trained respectively. The former is built for classifying the type of the RD, and the latter is built for calculating the inclination and RAAN of the RD. The simulation results show that two neural networks are well trained. The classification model has an accuracy of more than 99% and the mean square error of the regression model is less than 0.01°on the test set. Moreover, a serial strategy is proposed to combine the two surrogate models and a recognition tool is built to evaluate whether a lunar site could be reached. The proposed deep learning method shows the superiority in computation efficiency compared with the traditional double two-body model.
基金supported by the National Natural Science Foundation of China (Grant No.10902121)
文摘A circumlunar free return orbit design model that satisfies manned lunar mission constraints is established. By combining analytical method with numerical method,a serial orbit design strategy from initial value design to precision solution is proposed. A simulation example is given,and the conclusion indicates that the method has excellent convergence performance and precision. According to a great deal of simulation results solved by the method,the free return orbit characters such as accessible moon orbit parameters,return orbit parameters,transfer delta velocity,etc. are analyzed,which can supply references to constitute manned lunar mission orbit scheme.
文摘针对复杂轨道机动规划与实际问题紧密耦合,建模和求解复杂的难题,提出复杂轨道机动规划本体元建模方法,设计并实现了通用软件。分析轨道机动规划特点,抽象得到任务段、停止条件、控制变量和约束组成的MSCC(Mission control segment-Stop condition-Control parameter-Constraint)元模型体系,将MSCC元模型映射到软件设计,得到通用轨道机动规划软件类层次结构,采用C++语言实现了自主软件ATK.Planning,使轨道机动规划可以采用统一的方法描述和软件求解。针对快速交会和地月自由返回转移的仿真结果表明,软件仅通过人机界面配置就可以完成复杂轨道机动规划问题求解,收敛误差小于设定值,大大降低了任务设计时间。
