Abstract:

We propose a tractable approach to generate abort-safe trajectories for safe spacecraft rendezvous that guarantees safety (the spacecraft does not enter a keep-out set defined around the rendezvous target), despite process and measurement noise, and the possibility of partial propulsion failure. We use a combination of stochastic reachability, computational geometry, and optimization to synthesize a nominal rendezvous trajectory and its associated controller. The designed trajectory is such that safe recovery is also guaranteed with high likelihood in the event of a partial propulsion failure. The recovery controllers can be computed only when needed using offline pre-computation, thereby reducing the online computational effort. Numerical experiments show the efficacy of the proposed approach.