Design of Low Fuel Trajectory in Interior Realm as a Backup Trajectory for Lunar Exploration

Abstract

In case of a failure on a Hohmann-type translunar trajectory, a reconfiguration of the trajectory that utilizes the three body dynamics of the interior realm of Earth-moon system is proposed. The stable manifold and unstable manifold of a periodic orbit around L1 point extended toward the Earth side have homoclinic intersections. In the proposed method, after detection of a failure on the nominal trajectory, the trajectory is modified by small maneuvers so that the spacecraft can be kicked back by the moon and transferred to the unstable manifold. Then the spacecraft is returned to the moon side through the intersection with the corresponding stable manifold on the Earth side. The periodic orbit is used as a parking orbit so that the amount of delta-v at the moon orbit insertion can be reduced. Since the required amounts of delta-v at each individual maneuver are small throughout the reconfigured trajectory, it can serve as a solution for a backup trajectory in case of a main engine failure. Additionally, the long transfer time of the low-energy trajectory and good operability conditions in the interior realm provide an opportunity for diagnosis and repair of the failure.