The robot, designed to explore the moon's craters, is being demonstrated in Denver this week during the third Space Exploration Conference.

The rover must operate in continual darkness in extremely cold conditions with little power, NASA said, noting lunar soil -- known as regolith -- is abrasive and compact, so any ice the rover encounters would likely have the consistency of concrete.

Engineers demonstrated a drill capable of digging samples of regolith last year. That demonstration used a laser light camera to select a site for drilling, then commanded the four-wheeled rover to lower the drill and collect three-foot samples of soil and rock.

"These are tasks that have never been done and are really difficult to do on the moon," said John Caruso of NASA's John Glenn Research Center in Cleveland.

Engineers participating in development of the rover robot concept included scientists from four NASA centers, the Canadian Space Agency; Canada's Northern Center for Advanced Technology in Sudbury, Ontario, and Carnegie Mellon University's Robotics Institute.