Airless tires may be a lifesaver in military combat

It is not every day that you run into a company which is in the business of reinventing the wheel. An ambitious startup company in this central Wisconsin city is exploring this very challenge with a project to develop tires that can withstand extreme punishment, even those meted out in military combat zones. Wausau, Wisconsin-based Resilient Technologies, LLC is working on a four-year, $18 million project with the U.S. Department of Defense and the University of Wisconsin-Madison to research and develop a non-pneumatic tire for use on heavy-grade military vehicles such as Humvees. The project could be a lifesaver for the military: In many situations in Iraq, tires have proven to be weak links in Humvees that enemies target with improvised explosive devices (IEDs). “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,” says Mike Veihl, general manager of Resilient. “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.”

The company has made remarkable strides in just over two years of operations, cycling through literally hundreds of prototypes, developing subscale airless tires for lawn tractors, and finally the featured product: In April, Resilient installed a set of their creations on a Wausau-based National Guard Humvee, where it is undergoing rigorous on- and off-road tests.
Company representatives say that Resilient’s partnership with UW-Madison’s Polymer Engineering Center (PEC) has played a major role in setting the high-speed development pace. The center serves as a subcontractor in the project and provides two graduate students under the general direction of mechanical engineering professor Tim Osswald. In addition to conducting basic polymer research, the PEC works with dozens of companies, big and small, on materials testing and product development, says Osswald. The Resilient project presented one of the more complicated challenges his lab has seen, given the complete rethinking taking place in the design and the high levels of performance the tire must meet. The Wisconsin design breakthrough, first developed by Resilient’s in-house design and development team, takes a page from nature. “The goal was to reduce the variation in the stiffness of the tire, to make it transmit loads uniformly and become more homogenous,” Osswald says.