Application Of Interplanetary Superhighway Theory To The Trajectory Design Of Moon Exploration

Along with the development of space technology, deep space exploration is drawing more and more attention from the public. Trajectory design and optimization is one of the key techniques for deep space exploration. Trajectory design of the deep space probe, permitting several transfer trajectories for the same destination orbit, is more complicated than that of earth satellite. In this thesis, we focus on a new trajectory design for moon explore project, which needs less fuel than conventional Earth-to-Moon Hohmann transfer orbit.Firstly, the circular restricted three-body problem (CR3BP), which is a basic dynamical model in deep space exploration, is studied. Based on the Newtonian approach and unit normalization, the equation of CR3BP motion is derived. Accordingly, we get the five lagrangian points by computing the five particular solutions of CR3BP. And with the Jacobi integral, this thesis also gives the possible flight region of spacecraft in Earth-moon system at different Jacobi value.Secondly, with the Richardson three-order approximations solution as initial conditions, a Halo orbit around the lagrange libration point is designed by using of the differential corrections method. Based on linear systems theory and Poincare section approach, the approximation computation of the sable manifold and unstable manifold of halo orbit is derived.Thirdly, the trajectory design for moon exploration with EL2—LL2 case is designed by using of the IPS theory. We derive the transformation from Earth-Moon system to Sun-Earth system and make the stable manifolds of LL2 and the unstable manifolds of EL2 intersect in the configuration space. A transfer trajectory for moon exploration is given via the heteroclinic connection. Then, we use differential corrections method to modify the velocity of crossing point in order to generate transit orbit and non-transit orbit which save time trajectories. Another transfer trajectory is designed through conjection of transit orbit and non-transit orbit. The simulation shows that the EL2—LL2 case requires lessΔV than the conic case. But the flight time of the trajectory of EL2—LL2 case is longer than that of conic case .