New honeycomb tire is 'bulletproof'

Posted by Mark Rutherford

The University of Wisconsin-Madison and a Wausau, Wis., company have come up with a 37-inch, bullet and bomb-proof Humvee tire based on a polymeric web so cool looking there's no need for hub caps.

Resilient Technologies and Wisconsin-Madison's Polymer Engineering Center are creating a "non-pneumatic tire" (no air required) that will support the weight of add-on armor, survive an IED attack, and still make a 50 mph getaway. It's basically a round honeycomb wrapped with a thick, black tread.

The military wants an alternative to the current Humvee "run flat" tires, which despite the name, still need a minimal amount of air pressure to roll and can leave troops stranded after being shot or blown out.

"You see reports all the time of troops who were injured by an IED or their convoys got stranded because their tires were shot out," said Resilient's General Manager Mike Veih. "There's all sorts of armor on the vehicle, but if you're running in the theater and get your tire shot out, what have you got? You've got a bunch of armor in the middle of a field."

In developing the design, the Wisconsin team studied other airless tires, like the Michelin "Tweel," but in the end settled on lessons learned from nature.

The patent-pending design mimics the precise, six-sided cell pattern found in a honeycomb and best duplicates the "ride feel" of pneumatic tires, according to the developers.

"The goal was to reduce the variation in the stiffness of the tire, to make it transmit loads uniformly and become more homogenous," said mechanical engineering professor Tim Osswald. "And the best design, as nature gives it to us, is really the honeycomb."

This particular geometry also does a great job of reducing noise and heat levels while rolling-two common problems with past models.

Costs per tire are expected to be the same or less than current units. Delivery is anticipated for 2011.

Mark Rutherford is a West Coast-based freelance writer. He is a member of the CNET Blog Network, and is not an employee of CNET. Email him at markr@milapp.com. Disclosure.

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