Rendezvous and docking operations in near rectilinear halo orbits

Abstract

Rendezvous and docking (RVD) in non-Keplerian Near Rectilinear Halo Orbit (NRHO) presents unique challenges due to orbit-attitude three-body dynamics. This study subdivides the RVD process into three operationally distinct phases, each with specific technical requirements: the transfer and phasing phase, the loitering phase, and the terminal docking phase. A tailored strategy is developed for each phase, combining natural dynamical mechanisms with forced control methodologies to achieve mission objectives. In the transfer and phasing phase, leveraging Cauchy-Green tensor (CGT) stretching directions for low-energy orbital alignment. During the loitering phase, a CGT-derived drift trajectory is designed, while attitude-stabilizing flows are applied to ensure stable spacecraft orientation. Finally, for the terminal docking phase, prescribed performance control (PPC) enforces precise six-degree-of-freedom (6-DOF) control by enforcing strict transient and steady-state constraints. Numerical simulation demonstrates the effectiveness of this approach for RVD operations between a chaser spacecraft and a target space station in NRHO.