Time Shift Governor for Constrained Control of Spacecraft Orbit and Attitude Relative Motion in Bicircular Restricted Four-Body Problem

TL;DR

This paper introduces a control method using a Time Shift Governor for constrained spacecraft rendezvous and docking in the Bicircular Restricted Four-Body Problem, effectively managing constraints and attitude dynamics in complex orbital scenarios.

Contribution

The paper presents a novel control approach employing a Time Shift Governor to handle multiple constraints during spacecraft rendezvous in a complex four-body gravitational environment.

Findings

Successfully enforces constraints during RVD in simulations.

Validates the control method with numerical simulations.

Demonstrates effective attitude and orbit management in BCR4BP.

Abstract

This paper considers constrained spacecraft rendezvous and docking (RVD) in the setting of the Bicircular Restricted Four-Body Problem (BCR4BP), while accounting for attitude dynamics. We consider Line of Sight (LoS) cone constraints, thrust limits, thrust direction limits, and approach velocity constraints during RVD missions in a near rectilinear halo orbit (NRHO) in the Sun-Earth-Moon system. To enforce the constraints, the Time Shift Governor (TSG), which uses a time-shifted Chief spacecraft trajectory as a target reference for the Deputy spacecraft, is employed. The time shift is gradually reduced to zero so that the virtual target gradually evolves towards the Chief spacecraft as time goes by, and the RVD mission objective can be achieved. Numerical simulation results are reported to validate the proposed control method.