Abstract:

Libration Point Orbits (LPO) play a central role in lunar exploration of the 21st century. Long-term operations of both crewed and robotic assets on LPOs necessitate propellant-efficient and reliable station-keeping schemes. Recent developments highlight the importance of station-keeping schemes that not only maintain the geometric orbital regime but also avoid leading or lagging along the orbit as a result of a drifting phase. In this work, an optimization-based station-keeping algorithm for colinear LPO based on the x-axis crossing control, an event-based targeting scheme for impulsive maneuver design, is conceived. The optimization problem is cast as a sequential second-order cone program and incorporates an explicit constraint on the perilune pass epoch to ensure the steered trajectory follows the reference baseline without deviating in phase. The resulting formulation has easily interpretable tuning parameters that may be obtained directly from mission requirements. The algorithm is demonstrated through Monte-Carlo simulations on Gateway’s Near Rectilinear Halo Orbit (NRHO) in the high-fidelity ephemeris model with realistic error models