Resource-Aware Planning for Robot Operations at the Lunar Pole
Satellite observations have shown the likely existence of water ice at the lunar poles. Confirmation and exploitation of lunar ice will transform space exploration by providing fuel to support far-reaching exploration and enabling commercial endeavors. Because ice and other volatiles are trapped in lunar regolith, confirmation will require driving and drilling in the hostile environment of the lunar pole. Extreme temperature swings between sunlight and shadow mean that a rover may not survive more than one lunar day, or 14 Earth days, which is a very short time compared to the multi-year treks of rovers on Mars. With such a short operating window, every minute matters. Any decision to stop and survey for ice may mean that there will not be time to survey somewhere else later. A polar prospecting rover also faces other limitations, such as battery power. Solar panels can recharge batteries, but unless a robot’s movements are carefully planned, deep, cold shadows that shift with time could trap it without power and end its mission. Under a Small Business Innovation Research (SBIR) award, Astrobotic and Carnegie Mellon University are building a computer-aided mission planning tool to improve understanding of the trade-offs between mission goals and resource constraints. This mission planning software may be demonstrated as part of NASA’s Mojave Volatile Prospector field experiment, which simulates a drilling mission at a lunar pole, in October 2014. The ultimate goal is to use the software for an actual lunar prospecting mission that could happen as early as 2018. http://www.youtube.com/watch?v=q7eRRzi4ids&feature=youtu.be This video shows the mission planning tool in action in a simulation of Shackleton Crater, at the Moon’s South Pole. The colored line shows the planned path, with red indicating the robot has plenty of battery power at that point, and blue indicating low battery power. As shadows shift with time, the robot lingers in the sunlight to charge its battery before darting across a shadowed region to reach its goal.