Next time you're driving around on Mars and need to get your tire replaced, chances are good it'll look something like a revolutionary new version made by NASA and Goodyear. The mesh cage design can take a beating and roll right on.
OK, while it might be true that Martian tire shops are quite a long way off, NASA has a real interest in designing tires for the rovers that will roam around the planet in advance of any kind of human settlement on the Red Planet. Because the surface of Mars is extremely rocky, these rovers would best be served by a tire that could absorb the impact from a wide range of sharp, craggy rocks without suffering damage.
At the Airbus Mars Yard in the UK, NASA engineers just tested out a strong candidate, based on a design first announced by Goodyear in 2010 and which has been in development since 2017.
There, they equipped a rover with shape memory alloy (SMA) spring tires and set it loose to roam over the sandy rock-studded soil. The tires performed admirably thanks to the fact that they are made from a nickel-titanium alloy which, as NASA materials research engineer Santo Padula explains in the following video, has the ability to rearrange its atomic structure when force is introduced, and then bounce right back to its original shape.
While NASA has used SMAs before, the idea of applying them to tires is a new one, says the agency.
During the testing at the Mars yard, researchers gathered data about the stability and maneuverability of the tires, and also looked at how well they could handle a range of jabs from rocks. NASA says the tires "met all expectations" during the program. The mesh tires are so resilient that they can be caved in right down the rim and regain their shape as they roll along.
Now, the agency will be looking at both improving the tires and at ways the titanium-nickel SMA can be used in other space-based applications.
“My goal is to extend the operating temperature capability of SMAs for applications like tires, and to look at applying these materials for habitat protection,” Padula said. “We need new materials for extreme environments that can provide energy absorption for micrometeorite strikes that happen on the Moon to enable things like habitat structures for large numbers of astronauts and scientists to do work on the Moon and Mars.”
Source: NASA