Fail-Safe Spacecraft Rendezvous on Near-Rectilinear Halo Orbits

Future spacecraft missions require novel guidance and control policies that reduce fuel consumption, yield sparse thrust signals, and maintain mission safety even in the presence of faults. This paper presents an approach for rendezvous with a target in a near-rectilinear halo orbit that exploits the natural dynamics to reduce propellant consumption, and ensures passive safety in the presence of thruster failure. A chaser spacecraft that aims to rendezvous with a target is steered into coasting sets while simultaneously maintaining passive safety by avoiding the states that naturally collide with the target. Upon entering the coasting sets, the chaser's thrusters are disengaged, as the natural dynamics lead it into a goal set. Abort-safety is then demonstrated during final approach from the goal set to the target. The target is modeled in a full-ephemeris, high-fidelity, and quasi-periodic near-rectilinear halo orbit. Simulations demonstrate a reduction in maneuver fuel consumption, measured by delta-v, of up to 72.5% and a significant reduction of thruster on-time compared to prior work.