Flat Out Airless

by Clint Burgess


Rubber plays many roles in our daily routines and we don't put much thought into it. There isn't anything lavish or exciting about this simple compound -- rubber is what it is, with no frills or fanfare. The first rubber tires for motor vehicles were introduced in the late 19th century. Nothing has changed much since then except for sizes and a few construction tweaks, but there is finally something different - radically different -- on its way. Michelin, a French tire manufacturer, has been developing a product so cutting-edge it will revolutionize the industry. As the largest manufacturer of tires in the world, Michelin is pushing new limits in an effort to stay on top.


Their new development is called the Tweel. Remarkably, it doesn't use air or very much rubber. It's still round and it's still mounted on a vehicle in the traditional sense but it offers the possibility of a more hassle-free driving experience. The design of the tire can be broken down into four pieces. The first is a thin layer of rubber tire tread. It still uses rubber but less of it and in a more efficient manner. The next piece is a "shear band" that encircles the last two elements, which are the spoke section and the hub.


The initial benefits of a tire that is constructed without air are apparent. The idea of not worrying about changing a flat tire is a nice one, not to mention the repercussions of blowing a tire out at high speeds. In recent years, tire manufacturers have made a push to market run-flat tires. These tires allow motorists some additional time to make it to a safe stopping point after a flat tire has occurred. The Tweel uses that idea and takes it a step further. The rubber tire and tube are no longer the main components; instead, the Tweel uses its flexible spokes to create give in the tire. That allows for shock absorption as well as an increased sensitivity to road conditions. Another positive for the Tweel is that it eliminates the need for a spare tire, making more space available for storage inside vehicles.


At this point, the Tweel is only in its developmental stage. It is being tested rigorously before release on the market to avoid any arguments about its superiority to conventional tires. There have been some reports with the Tweel of excessive noise, friction and bumpiness. Engineers have already pinpointed some design flaws, however, and can now move forward on improvements. The Tweel's intensely sensitive rubber-to-the-road feel may make for a bit of a bumpy ride at present, but that's not an insuperable obstacle.


A wheel like this could instigate a shift in the way tires are made and designed. It has been more than a century since the advent of the tire in its current incarnation. While Michelin has been a pioneering force in the industry, its innovation of the Tweel seems likely to inspire other manufacturers to develop tires designed in a similar way. If so, Michelin will have to bump up its 10-to-15-year development period they have projected for the Tweel. If it takes that long, they may just get beat at their own game.





Publication date: 05/12/05