Performance of a solar-powered robot for polar instrument networks

The Cool robot is a four-wheel-drive, solar-powered autonomous vehicle designed to support summertime science campaigns in Antarctica and Greenland. We deployed the robot at Summit Camp, Greenland, during 2005 to validate its power budget and to assess its unique control system that matches solar power input with power demand as the robot drives over rough terrain. The 61-kg robot drove continuously at 0.78 m/s on soft snow, its 160-W average power demand met by solar power alone under clear skies when sun elevation exceeded 16deg. The power-control system reliably matched input with demand as insolation changed during the tests. A simple GPS waypoint-following algorithm provided reliable autonomous navigation over periods of 5-8 hours. The data validate our design models and indicate that the Cool Robot exceeds its design goal of carrying a 15-kg payload 500 km in two weeks on the Antarctic plateau