Proximity approaches and design strategies for non-cooperative rendezvous* V-bar hopping vs. spiral approach

Abstract

As the amount of debris in orbit increases, so does the risk of collisions and their seriousness. All nations involved with space operations acknowledge this growing threat. One solution receiving increased attention is active debris removal. The first step in a debris removal mission would be to approach the debris. In this phase, it is important to ensure passive abort safety and to guarantee the robustness against collisions in the case of off-nominal thruster burns, that may be caused by spacecraft anomalies such as navigation sensor or actuator failures. This paper compares two types of passive abort safe trajectories –the V-bar hopping and spiral approaches– considering the ¦V budget, the duration of operations, and variation in the line-of-sight vector to the target. This paper also proposes design strategies for determining the parameters in the two candidate trajectories, considering passive abort safety. The robustness of the trajectories against collisions due to off-nominal thruster burns is also demonstrated through Monte Carlo simulations. The paper investigates which trajectories are suitable for an active debris removal mission to a non-cooperative target.