Incorporating Periodic and Non-Periodic Natural Motion Trajectories into Constrained Invariance-Based Spacecraft Relative Motion Planning

摘要

Spacecraft relative motion planning is concerned with the design and execution of maneuvers relative to a nominal target. These maneuvers must account for spacecraft dynamics, and possibly for constrained thrust capabilities and inclusion and exclusion zone constraints, where the latter can be non-linear and non-convex. In this paper, a scheme for generating a feasible trajectory for spacecraft relative motion based on a graph search applied to a set (virtual net) of closed (periodic) natural motion trajectories (NMTs) is extended to incorporate open (non-periodic) NMTs. This extension increases the flexibility of the scheme and can provide other advantages, such as reduced fuel use. Safe positively invariant tubes are constructed around each trajectory in the virtual net and used to determine node (vertex) adjacency and connection information such that transitions between trajectories corresponding to adjacent nodes can be executed while satisfying the imposed constraints.