For more than 150 years, tires for cars, bicycles and other vehicles have had one thing in common. No, not just that they are round, but that in some fashion, the tires are filled with air. However, a number of companies are working on airless tires that use space-age materials that could make flats a thing of the past.
The air ring of grievances
The basics in tire design have barely changed since before man even invented the first car. In 1846, according to Car and Driver, Robert Thomson, a Scottish engineer, came up with the idea of a rubber tire tread mounted to a wooden wheel with an air-filled tube inside the tire, thus inventing the pneumatic or air-filled tire.
Since then, there have been few revolutionary changes aside from discarding the inner tube. The modern tire we are familiar with today hasn’t changed much; there is a rubber shell with a tread pattern and air in between it and the wheel. Several companies are now out to change this pattern and come up with something more modern and beneficial.
Bridgestone is on it
Currently, Bridgestone is working on an airless tire design. Bridgestone’s airless tires are only in testing; it will be years before they are ready for market. Bridgestone unveiled the airless tires at the 2011 Tokyo Motor Show, according to Gizmag.
The 9-inch wheels use a hard aluminum inner wheel, which connects the wheel to a rotor and wheel hub. Between that and the solid rubber tread, is a densely layered “honeycomb” structure of rigid but flexible thermoplastic resin spokes. The plastic material provides the rigidity and flexibility normally provided by air. Bridgestone has tested the tires with very small cars, but plans on testing with full-size vehicles in coming years. For all those that are eco conscience out there, Bridgestone has you covered; they make the tires entirely from recyclable materials.
Michelin, according to Car and Driver, similarly experimented with an airless tire design called the “Tweel,” a portmanteau of “tire” and “wheel.” The Michelin Tweel similarly used hard plastic spokes between a central wheel hub and the tread. Michelin tested the Tweels on road cars and, according to HowStuffWorks, construction equipment successfully. The Tweel was debuted in 2005, but since then, little has come of the project. As of 2009, according to CBS, Michelin still estimated the Tweel was up to a decade away from being ready for the market.
There are some hitches. The reason why solid rubber tires gave way to the pneumatic tire in the first place was that the ride on solid tires is atrocious. Bicyclists can still buy them, though many bicycle shops, according to LiveStrong.com, cycling legend Lance Armstrong’s website, often refuse to stock them as solid tires can damage the tire rim and don’t provide nearly as good of traction off-road. There are also airless tires for construction equipment, though they aren’t suitable for road use.
Tweel tests also revealed problems. According to CBS, the spokes would begin to vibrate dramatically at 50 miles per hour, creating considerable road noise. However, when tested against your common everyday tire, Tweels kept up to the standard performance.