Meet Axel: NASA's 'Marsupial' Rover to Explore Craters

NASA's Axel rover is a whirling robot designed for the most challenging terrain on the Moon and beyond. NASA refers to a robot like the Axel rover as a 'tethered marsupial rover' because it would spend most of its time attached to a larger vehicle until it is needed.

The Axel rover prototype is built like a yo-yo; its tether is wrapped around its central axle. The other end of the tether would be attached to a larger, conventional rover robot, like the Spirit and Opportunity rovers on Mars. The Axel rover solves a problem that bedevils these conventional robots. When Spirit, for example, encounters a crater, it cannot descend and explore.

However, the Axel can; it lets gravity pull down, whirling the rover around. It uses its arm to gather samples; its stereoscopic cameras gather visual details. When it has finished its duties, it can wind itself back up to the top, to be stored again for later use.

According to Pablo Abad-Manterola, one of the contributing CalTech students:

"Right now, it's really risky for astronauts or robots, for example, like Spirit an Opportunity to go into craters. The ground is too loose and the slopes are too steep. So it's too risky for those robots to get into those craters and perform any interesting science. So this robot would be very useful for those types of scenarios, where you can really dive into those craters, pick up some samples, and really analyze them and tell us something really new and interesting about Mars or the moon, for example."

The Axel rover is really a marvel of simplicity. With just three actuators, it can control its wheels and trailing link. The robot can pick and choose its way down a slope, even turning in place if necessary.

"Axel can readily support different wheel types and sizes ranging from large foldable wheels to inflatable ones. In this way, it can traverse steep and rocky terrains, and tolerate strong impacts during landing or driving. Additionally, Axel is designed with co-location of its sensors, actuators, electronics, power, and payload inside the central cylinder. This configuration provides compactness for launch, and robustness against environmental extremes in planetary missions."

The whirling Axel rover reminds me of those wonderful whirling tripedal spider robots from Arthur C. Clarke's 1972 novel Rendezvous With Rama.

• New Video Robot Yo-Yo: NASA?s Novel Axel Rover
• New Video - Spirit on Mars: NASA's Little Rover That Could
• Future of Mars Exploration: What's Next?

?(This Science Fiction in the News story used with permission of Technovelgy.com)