Safe Trajectories for Autonomous Rendezvous of Spacecraft

Autonomous spacecraft rendezvous is an enabling technology for many future space missions, but anomalies in recent flight experiments suggest that safety con- siderations will play a critical role in mission success. This paper presents a method for online generation of safe, fuel-optimized rendezvous trajectories that guarantee passive collision avoidance for a large class of anomalous system behaviors. We examine the cost of imposing safety as a problem constraint and of additional con- straints that guarantee infinite horizon passive collision avoidance while enabling future docking retries. A convex collision avoidance formulation was introduced and determined to provide computationally fast solutions at a small fuel expense. Several examples using both rotating and non-rotating targets are presented to demonstrate the overall benefits of incorporating these safety constraints when compared to nominal trajectory design techniques.