Time-Dependent Planning for Resource Prospecting

Future planetary robotics will require path planning that ensures rover safety while responding nimbly to new information and evolving goals. Such missions include prospecting for ice at the lunar poles. These challenge robotic explorers in ways not encountered in equatorial missions that benefit from high solar elevations. Longdistance traverses must be achieved over short timescales. The grazing sun angles cause substantial, time-varying shadows that require paths to consider rover temperature and power balance in addition to terrainability. This paper details a hierarchical planner that considers these elements to rapidly generate long-distance paths. The planner has two components: a high-resolution planner that pre-computes feasible trajectories over short distances and a low-resolution mission planner that leverages the results of the kinematic planner to quickly find long-distance, feasible paths. Planner capabilities are demonstrated in simulated traverses on the poles of the Moon.