New Goodyear/NASA airless moon tire may have Earthly applications

Engineers at Goodyear and the National Aeronautics and Space Administration (NASA) have created an airless tire to move large, long-range vehicles across the surface of the moon.

The invention drew raves from federal lawmakers during a recent NASA “Day on the Hill” exhibit in Washington, D.C.

“I spoke with 10 to 15 members of Congress and about 60 staffers,” reports Vivake Asnani, NASA’s principal investigator at the Glenn Research Center in Cleveland. “Virtually everyone I spoke with was blown away by the idea that this technology may one day be used, not only for extraterrestrial vehicles, but also, perhaps, for vehicles here on Earth.”

The new “Spring Tire” with 800 load-bearing springs is designed to carry much heavier vehicles over much greater distances than the wire mesh tire previously used on the Apollo Lunar Roving Vehicle (LRV). The new tire will allow for broader exploration and the eventual development and maintenance of a lunar outpost.

“With the combined requirements of increased load and life, we needed to make a fundamental change to the original moon tire,” says Asnani. “What the Goodyear-NASA team developed is an innovative, yet simple network of interwoven springs that does the job. The tire design seems almost obvious in retrospect, as most good inventions do.”

The Spring Tire was installed on NASA’s Lunar Electric Rover test vehicle and put through its paces at the Johnson Space Center’s “Rock Yard” in Houston, where it successfully performed its assigned duties.

“This tire is extremely durable and extremely energy efficient,” notes Jim Benzing, Goodyear’s lead innovator on the project. “The spring design contours to the surface on which it’s driven to provide traction. But all of the energy used to deform the tire is returned when the springs rebound. It doesn’t generate heat like a normal tire.”

According to Goodyear engineers, development of the original Apollo lunar mission tires and the new Spring Tire was driven by the fact that traditional rubber, pneumatic tires used on Earth have little utility on the moon. This is because rubber properties vary significantly between the extreme cold and hot temperatures experienced in the moon’s shaded and directly sunlit areas. Furthermore, unfiltered solar radiation degrades rubber, and pneumatic tires pose an unacceptable risk of deflation.

The Spring Tire does not have a “single point failure mode,” Asnani asserts. “What that means is that a hard impact that might cause a pneumatic tire to puncture and deflate would only damage one of the 800 load-bearing springs. Along with having this ultra-redundant characteristic, the tire has a combination of overall stiffness yet flexibility that allows off-road vehicles to travel fast over rough terrain with relatively little motion being transferred to the vehicle.”

A video featuring the technology can be viewed at www.nasa.gov/offices/ipp/video/hallmarks_moontires_index.html.

For more information, visit www.goodyear.com and www.nasa.gov.