Analysis Approaches For Precision Reachable Sets Of Manned Lunar Orbits Using Numerical Continuation Theory

It is an actual choice to explore and develop the moon for China’s manned space mission reaching on a higher step,and respecting to the rule of manned space development and the national conditions of developing countries.“Global access” and “Any-time return” have made the orbital precision reachable sets calculation problem to be a hotspot for manned lunar mission,and the problem is also one of the key research questions for China’s manned lunar mission in the future.Based on the practical problems in China’s manned lunar mission argumentation and a pre-research project about it,the work expands new theories and methods,systematically studies the precision reachable sets about lunar module trans-lunar trajectory,manned spacecraft trans-lunar trajectory and trans-earth trajectory,and the planning approach for a whole manned lunar mission.The main research results are as follows:A method is proposed for analyzing and calculating the precision reachable set of lunar module trans-lunar trajectories using numerical continuation theory.In order to clearly describe the reachable region of the lunar surface,a reverse double two-body orbit model(RDTB)is established based on the selecentric LVLH(local vertical & local horizontal coordinate system)at the time of perilune.The characteristics of the reachable set are analyzed using RDTB,and the method using numerical continuation theory is proposed for the precision reachable set.The factors and their impact to the reachable set are analyzed.A method is proposed for analyzing and calculating the precision reachable set of manned spacecraft trans-lunar trajectories using numerical continuation theory.A novel model with four-phase two-body conic trajectories is established for computing the reachable set of the circumlunar free-return trajectories(CFRT).Further,a strategy is established for computing the precision reachable set of CFRT using numerical continuation theory and the suggested reverse and forward orbital integral model with high precision perturbation.The factors and their impact to the reachable set of CFRT are analyzed.The models of the hybrid orbit and selecentric elliptical orbit for extending the reachable set of CFRT is designed,the additional velocity increment and flying time are analyzed for Global Access.A method is proposed for analyzing and calculating the precision reachable set of manned spacecraft trans-earth trajectories using numerical continuation theory.A improved double two-body model is established for computing the reachable set of the trans-earth trajectories,and then a strategy is established for computing the precision reachable set of the trans-earth trajectories using numerical continuation theory.The factors and their impact to the reachable set of the trans-earth trajectories are analyzed.Aimed at Any-time Return from low lunar orbit(LLO)to earth and adjusting the flight time on the way home to earth in emergency,to expand the reachable set of the trans-earth trajectories,the strategies for orbital maneuvers are designed,and the additional velocity increment cost is analyzed.A planning method of the total manned lunar mission flight plan supported by low lunar orbit rendezvous is proposed.The main constraint conditions of manned lunar mission are analyzed,which is supported by low lunar orbit rendezvous and constituted of a separation of crew and cargo when launch from earth.The overall planning method is put forward on the flight plan,and then a series of methods are designed for planning the windows of the main transfer trajectories.A series of applied soft-wares to the engineering project are developed integrated the main research results in this dissertation.For computing the precision reachable sets of transfer trajectories and the total flying plan in manned lunar mission,a serial semi-analytical models based on the double two-body assumption are established to compute the trajectories in Earth-Moon space in this dissertation.The supposed approaches for computing precision reachable sets using numerical continuation theory has certain theoretical innovation significance.The analysis results of reachable sets of transfer trajectories answered an amount of important problems of China’s manned lunar mission argumentation,the supposed nominal flying mission planning methods have solved the actual difficulties in a pre-research project from China manned space agency about future manned lunar mission,and they have high practical value in a prospective manned lunar engineering.