Clemson, Milliken, Michelin Team For Lunar Wheel Project

Researchers at Clemson University, Clemson, S.C., and Milliken & Company, Spartanburg, are
working with Michelin North America Inc., Greenville, to improve tire tread materials that may be
used on National Aeronautics and Space Administration (NASA) Moon rovers.

Michelin is testing its new non-pneumatic Lunar Wheel, based on its Tweel non-pneumatic tire
technology, on the next generation of All-Terrain Hex-Legged Extra-Terrestrial Explorer (ATHLETE)
Moon rovers as part of a NASA Lunar Analogs testing and evaluation project. The ATHLETE rover is
able to navigate undulating as well as extremely rough or steep terrain such as is found on the
Moon’s surface; therefore, the tread and wheels must be tough yet flexible. The materials also must
endure extreme temperatures and be resistant to ultraviolet and cosmic radiation.

Clemson researchers are in the process of identifying the best tread materials. Fabric
possibilities include nonwoven felts, flat weaves, and cut- and loop-pile fabrics. Possible fibers
include polyaramids, polytetrafluoroethylenes, polyamides, polyimides and polyethylene
terephthalates. Researchers also are designing test equipment and developing computational models
to create tire-sand traction systems that eventually could result in improved tread material.

March/April 2009