Managing Spacecraft Memory Buffers with Concurrent Data Collection and Downlink

Abstract

Space mission planning/scheduling is determining the set of spacecraft activities to meet mission objectives while respecting mission constraints. One important category of mission constraints is data management. As the spacecraft acquires data via science instruments and engineering telemetry, it must store the data on board until it is able to downlink the data to ground communications stations. Because onboard storage and communication opportunities are often limited, this can be a challenging task. This paper first describes the general problem of onboard memory management for spacecraft that allow concurrent data collection and downlink activities. Then, a fast, intuitive heuristic is presented for solving this problem, and its use on the Rosetta comet rendezvous mission is evaluated. Finally, different local heuristics are compared for a greedy search to a global graph-based solution, measuring performance in terms of runtime and robustness to downlink buffer overflow. The results show that local he...