A Modified Targeting Strategy for Station-Keeping of Libration Point Orbits in the Real Earth-Moon System

Abstract

In this paper, a modified targeting strategy is developed for missions on libration point orbits (LPOs) in the real Earth-Moon system. In order to simulate a station-keeping procedure in a dynamic model as realistic as possible, LPOs generated in the circular restricted three-body problem (CRTBP) are discretized and reconverged in a geocentric inertial system for later simulations. After that, based on the dynamic property of the state transition matrix, a modified strategy of selecting target points for station-keeping is presented to reduce maneuver costs. By considering both the solar gravity and radiation pressure in a nominal LPO design, station-keeping simulations about fuel consumption for real LPOs around both collinear and triangular libration points are performed in a high-fidelity ephemeris model. Results show the effectivity of the modified strategy with total maneuver costs reduced by greater than 10% for maintaining triangular LPOs.

Relative Dynamics and Modern Control Strategies for Rendezvous in Libration Point Orbits

“…Folta et al [14] extended the concept of the Target Point strategy to include optimality considerations by combination with a global search method and an orbit continuation method, resulting in a discrete control strategy which was successfully used for operational station-keeping in the ARTEMIS mission [15]. Recently Jin and Xu [16] proposed a modified strategy for selecting target points for LPO stationkeeping to reduce manoeuvre costs in the real Earth-Moon system. Extensions to more complicated multi-body contexts have also been accomplished; Carletta et al exploited the Hamiltonian formalism to develop a linear feedback compact station-keeping law in the Sun-Mars elliptic restricted four-body problem LPOs [17].…”