One of the challenges of exploring distant worlds is the variety of terrains that a vehicle might encounter there. There could be flat planes, which are relatively easy to traverse in a wheeled vehicle, and there could be steep slopes, which are much harder. That’s why NASA is developing a new type of rover that can transform to take a shape most suited to the environment.
The DuAxel rover is made up of two individual rovers with two wheels each, both called Axel. Together, the four-wheeled rover can travel across rugged terrain and drive across considerable distances. But when it approaches difficult terrain, the two Axels can split apart, with the rear one staying in place while the front one moves forward on a single axel. The two remain connected by a tether, and the front half can investigate hard-to-reach objects by rappelling down slopes while staying safely connected to its back half.
To find out if the concept worked as well in practice as it does in theory, NASA engineers took a sample of the rover to the Mojave Desert in California and put it through a series of tests that simulated the kinds of challenges a rover might encounter on another planet.
The rover aced its tests, according to Issa Nesnas, a robotics technologist at JPL: “DuAxel performed extremely well in the field, successfully demonstrating its ability to approach a challenging terrain, anchor, and then undock its tethered Axel rover. Axel then autonomously maneuvered down steep and rocky slopes, deploying its instruments without the necessity of a robotic arm.”
With the rover able to split in this way, NASA says it could allow the exploration of features like crater walls, pits, scarps, vents, and other extreme terrains on distant worlds. It’s possible that in the future, multiple Axel robots could be combined together in a modular system to haul heavy payloads, or one robot could replace another if it failed mid-mission.
“DuAxel opens up access to more extreme terrain on planetary bodies such as the moon, Mars, Mercury, and possibly some icy worlds, like Jupiter’s moon Europa,” Nesnas said.
For now, the team will continue refining DuAxel and wait for it to be assigned a destination to explore in the future.
