If the history of the tire took on significant meaning with the invention and popularization of tires from 1895 thanks to the Michelin L'Éclaire (the first vehicle to have them), which is based on the process of vulcanizing rubber of Charles GOODYEAR in 1839 and the invention of the inner tube by Dunlop in 1887. These two elements: rubber and air, have since played an essential role in the production of tires as we know them.
However there is in the history of the tire, a part of which we know little and which could well be part of the future of the tire.
Thus in the early 1900s, following the shortage of rubber and the difficulty of filling tires with air during the First World War, the Germans designed in 1916 a steel spring tire, on a Protos, which was also to be more reliable than rubber tires and which was to equip military vehicles as a priority.
Across the Atlantic in the United States of America, Mr. JV Martin of Garden City, New York created a safety tire that used hardwood hoops wrapped in rubber, and hard rubber spokes that s intersected. This tire is said to have undergone successful testing but has never been successful.
An idea that has made its way, since NASA itself has developed this competition with other materials for their second generation ATHLETE lunar vehicle.
Later still, and a century later than the original idea, Michelin is preparing the future of the tire with the revival of this concept with its tire clumsily nicknamed the "Tweel", this combination of tire and wheel without air s turned out to be quite difficult to develop. The properties of a pneumatic tire allow adjustment of handling (lateral stability), ride quality (shock absorption) and noise reduction. The total absence of pressurized air affects all three aspects. The Tweel consisted of a thin synthetic rubber tread on the outside, wrapped around a composite plastic band to provide road compliance and support and shock absorbing polyurethane. The spokes, themselves, could then be made to different thicknesses to adjust the Tweel's handling capabilities and ride quality, from ultra-firm to more compliant. Finally, a rigid aluminum hub was used in the center, where the Tweel would be attached to the vehicle.
The construction configuration of the Tweel allowed for strong structural support in place of air, as well as significantly increased tread life, up to three times longer than a standard tire. Another huge advantage of the airless tire is the low replacement cost since only the rubber tread needs to be replaced, rather than the entire tire/wheel structure. The first vehicles to demonstrate the new technology were an Audi A4 and a Segway personal transport vehicle, although it was said that Michelin planned to release their Tweel first for military and construction use. In 2011, a company by the name of Resilient Technologies made its own move and developed the TNP (non-pneumatic tire) for military use and planned to test with the government in what is sure to be a lucrative contract. The claims are impressive, indeed. The spoke construction differs significantly from the Tweel spoke configuration, in that it uses a super strong honeycomb structure. The TNP claims a tread life of 100,000 miles and is, most importantly, highly blast resistant.
Japanese tire company, Bridgestone, did their own research and as recently as 2011 they debuted their own concept of non-pneumatic tires at the Tokyo Motor Show. The construction of their version mimicked the Tweel almost exactly, except for the use of inner and outer spokes that run in opposite directions, as opposed to the V-shaped spokes of the Tweel. Their claim was that noise and vibration for their version was not an issue. Bridgestone's strong performance is also a boon for environmentalism as the materials are much easier to recycle than standard synthetic rubber, hence the interesting green and black color scheme, most likely.
To close the loop, the tire manufacturer Michelin has developed a tire without compressed air and is puncture-proof, which will be marketed for cars in 2024 even if it has already been used for a few years in the industrial sector.
Called Uptis (Unique Puncture-proof Tire System), it is derived from the “Tweel” technology that Michelin developed several years ago. It is a wheel-tire assembly with a system of spokes and a shearing outer ring which is supposed to reproduce the behavior of a classic tire. But while the Tweel can only operate at low speeds, Michelin assures that the Uptis can be used under normal conditions by a passenger car.