Study On Integrated Window For Manned Lunar Mission

The launch window is the aggregate of spacecraft’s feasible launch time intervals.From the scale of time, it can be divided into the annual window, the date window andthe zero window. For a manned lunar mission, studies on the launch window areessential to ensuring the lifesaving security of astronauts and the task’s success. Thisdissertation studies the constraints, dynamic models and optimization approaches of themanned lunar launch window planning problem. The main achievements obtained aresummarized as follows.The Earth-to-Moon transfer window for manned lunar missions is designedand analyzed. The constraints on the Earth-to-Moon transfer window are analyzed. Thetrajectory planning model is established using the translunar time as the design variable.Moreover, the calculating approach combing the analytical and the numerical method isproposed. Using the presented programming model and approach, the Earth-to-Moontransfer launch window is successfully obtained and analyzed.The launch window based on the near-Earth orbit rendezvous and docking(RVD) is studied. The constraints on the launch window of the near-Earth orbit RVDare analyzed. The calculating method of the launch window, which can satisfy theseconstraints, is developed. Using the proposed method, the launch windows of differentnear-Earth assembly modes are successfully obtained and analyzed.The lunar ascent and rendezvous launch window is designed and analyzed.The main constraints on the lunar ascent and rendezvous launch window are analyzed,and then the corresponding optimization design model is established. The selection ofthe lunar ascent and rendezvous launch window is transformed into an optimizationproblem, which is then solved by the hybrid approach integrating the Gausspseudospectral method and the direct shooting method.In conclusion, three calculating approaches for the selection of the launch windowfor manned lunar missions are studied in this dissertation. The simulation results a nd theanalysis conclusions can have some theoretical significance and application value in theChina’s future manned lunar missions.