In 11th International Workshop on Planning and Scheduling for Space (IWPSS), pages 168–175, Berkeley, California, USA, July, 2019. Paper abstract bibtex
Mapping target bodies by imaging as much of the surface as possible is a common scientific goal for space missions where a spacecraft is orbiting a body, such as a comet, asteroid, or planet. An observation schedule to achieve the mapping goal is generally generated on the ground and then uploaded to the spacecraft. However, without some re-planning capa- bility onboard, opportunities may be lost due to observation failures or unexpected changes in resource availability. The computational and memory restrictions for spacecraft make it difficult to perform the geometric reasoning and calculations required to select observations to achieve the mapping goal onboard, meaning that any re-planning capabilities are also limited. In this paper we present a method for robust map- ping by re-planning observations onboard using pre-compiled backup observations. The nominal schedule and backup ob- servations are generated using the Compressed Large-scale Activity Scheduler and Planner, which are then translated into a Task Network and goal definitions. These can be used by MEXEC, an onboard planning and execution software. We demonstrate our method using a hypothetical scenario of a spacecraft orbiting a comet.