NASA is building a six-legged robot that can walk or roll on wheels, and, it hopes, ultimately help set up a habitat on Mars for the later arrivals of astronauts.

The robot, dubbed Athlete, has been in development for the past five years at NASA's Jet Propulsion Laboratory, said Brian Wilcox, Athlete's principle investigator. The robot is designed to move easily across the various types of terrain on the moon, on Mars or even on an asteroid.

The ATHLETE (All-Terrain Hex-Legged Extra-Terrestrial Explorer), a six-legged robotic vehicle under development by NASA, will set up human habitats on Mars. (Photo courtesy of NASA/JPL)

With a wheel attached to the end of each of its six legs, Athlete can roll across smooth terrain, and then retool itself when needed to move slowly across rugged or rocky terrain. The hexagonal machine stands about 10 feet off the ground when its legs are fully extended. It can step over a 10-foot wall and is designed to carry payloads of more than 14.5 tons on Mars.

"Athlete is being designed for the moon or Mars -- really any terrestrial body that has moderate gravity," Wilcox said. "We could have one or two sets [of these robots] on Mars by the time humans get there."

He added that NASA expects Athlete to be ready for a robotic mission to Mars by 2015.

Wilcox said he expects that two or three pairs of Athlete robots will be working on Mars before astronauts arrive there. Each Athlete will be designed to carry a cylindrical piece of human habitat in to the planet, and then connect them using tools like grippers, drills and scoops stored in their individual holsters.

Once the astronauts arrive, the Athletes would help them build berms and would be used to carry payloads of habitat materials brought to the planet aboard the astronauts space ship. The robots could also carry the astronauts to the new base camp.

Athlete is also designed to work alongside the 300-pound Robonaut robot that's slated to be carried to the International Space Station aboard the NASA space shuttle Discovery in September. Robonaut, which is equipped with two arms and two hands, will permanently reside on the space station.

NASA has long been working to build robots that can prepare areas of the moon or Mars for humans and later work alongside the astronauts.

Wilcox noted that NASA engineers are still working on mechanisms that will enable the robots to walk. Athlete, at this point, moves one leg at a time, enabling the other five to stabilize it, he said.

Wilcox described the robot's movements as slow but "extremely agile," -- a good combination for moving across rocky terrain.

NASA engineers are hoping that giving Athlete the ability to walk will keep it out of the trouble that trapped the space agency's Mars Exploration Rover Spirit.

NASA in January abandoned efforts to free Spirit from where it became stuck in dirt on the Martian surface after six years of roaming the Red Planet and sending back constant feeds of scientific information.

Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at @sgaudin, or subscribe to Sharon's RSS feed . Her e-mail address is sgaudin@computerworld.com.