Local Lyapunov Exponent Augmented Differential Corrections Process for Cislunar Trajectory Targeting

Abstract

Differential correction algorithms are frequently used for spacecraft trajectory targeting to produce feasible trajectories on the ground and on-board spacecraft. These targeting algorithms can satisfy numerous constraints imposed by mission designers, such as position and velocity continuity, minimum or maximum altitude, apsis, declination etc. By adding information about patch point state sensitivity via local Lyapunov exponents (LLEs) to the targeting process, a reduction in mission ∆V can be achieved without adding additional constraints to the system. The general objective of this work is to augment the two-level targeting differential corrections algorithm with an LLE informed impulsive maneuver placement algorithm to form an augmented two-and-a-half-level targeter. NASA’s Artemis I mission is used as a baseline trajectory. An LLE maneuver placement procedure is demonstrated, resulting in a ΔV reduction of 276.6 m/s, a 16.26% reduction relative to the baseline. The LLE maneuver placement is then incorporated into the targeting algorithm, resulting in a ΔV reduction of 290.4 m/s, a 17.07% reduction compared to the baseline trajectory.