Tires evolve to spend less energy and even lose air

What is now called a tire emerged as a solid rubber rim. Thanks to the vulcanization process, created 183 years ago by Charles Goodyear (1800-1860), these strips coated wooden or iron wheels and rolled uncomfortably on bicycles and carriages.

Air only entered history in 1888, when John Boyd Dunlop (1850-1921) installed a filling chamber and revolutionized the component structure. But the wheel turns, and everything can change again.

The evolution of cars has made manufacturers invest in solutions that increase safety and reduce fuel consumption.

While an electric car can gain precious kilometers of autonomy with the use of new tire compounds, avoiding sudden pressure loss is essential for an autonomous vehicle not to be involved in accidents. The air can therefore leave the scene. Or not.

For Michelin, the future combines tire and wheel in a single package. Uptis (acronym for unique puncture-proof tire system) is advertised as revolutionary, as it eliminates the need to be inflated for full operation.

Although it was first introduced in 2005 (under the name Tweel) and applied commercially to heavy machinery, the technology is only now ready to make its way to passenger cars, which is expected to occur in 2024.

Éric Vinesse, executive vice president of research and development at Michelin, explains that the development of the Uptis is done in collaboration with General Motors. “This partnership further strengthens our purpose of innovating, related to the Vision concept”, says the executive.

The concept mentioned by Vinesse includes the production of biodegradable tires by 3D printers, which would facilitate disposal and recycling. This idea belongs to a more distant future, while Uptis is part of the present. Its first application should be in the electric Chevrolet Bolt, which has been used in tests.

Yeah, it’s weird. Viewed in profile, Michelin’s airless tire has small spokes that deform as the car moves, and it looks like the sidewall —or sidewall—has come off.

By forming a unique set with the wheel, Uptis will depend on partnerships with more automakers to become viable. It is possible to assume that the replacement cost will be high, but Michelin does not yet give details on this.

Other brands have tested the solution proposed by the French manufacturer, but have taken other paths. Italian Pirelli, for example, opted for a tire that can automatically cover a puncture.

It is a jelly-like material. “When a nail penetrates rubber, for example, the hole is sealed around it”, explains Roberto Falkenstein, Pirelli’s director of research and development.

The technology called Seal Inside consists of a sealing layer that is vulcanized with the tire. Sales began at the end of 2021, with prices lower than the “run flat” options – which, because they have a more rigid housing, can run even after being damaged.

The first Seal Inside models are aimed at SUVs with urban appeal. In the 215/55 R17 measure (used, for example, in the Honda HR-V), the price is approximately R$ 850 per unit in the aftermarket. It is basically half the amount charged for a “run flat” of similar dimensions.

Pirelli also carries out tests with 5G technology. Through sensors, the tires monitor the trajectory and send data in real time.

“Soon we will have autonomous cars, and from then on the tire has to see a little for the driver”, says Falkenstein. “When passing in a puddle, the car will alert other users and help control traffic. It also works on an icy road in Europe or in front of potholes in Brazil.”

All these innovations need to be accompanied by a reduction in fuel or electricity consumption. That’s where the green tires come from, which increase autonomy by being less resistant to rolling. But that doesn’t mean they have less grip.

“The tires stop losing internal energy, but without interfering too much with the contact with the ground. If we compare a product today with that of ten years ago, the reduction in consumption reaches something between 6% and 8%”, says Falkenstein.

The need for weight reduction made BMW not use a “run flat” set in the iX electric utility, unlike what happens in models equipped with a combustion engine.

“We do gymnastics to lighten the weight on electric models, since gasoline uses one hundred times more energy than a kilowatt”, explains Emilio Paganoni, responsible for BMW’s training area in Brazil. The iX uses a specific tire to reduce drag, it even has a symbol that shows it was developed for use in electric cars.”

In addition to saving energy, it is necessary to reduce the noise level. “Before, there was so much noise in the car that the tire was just one more, but now, with the silence of electric vehicles, it has become a critical point”, says Roberto Falkenstein, from Pirelli.

Despite so many innovations, the technology involved in the production of tires does not advance as fast as with other equipment that goes into cars. This is the opinion of Rubens Carvalho, Dunlop distributor and partner of VC One, a company focused on mobility solutions.

“We have materials with more resistance, but, in essence, the tire has not changed since it was invented. I believe that it will still have longevity in this current standard, until a technology actually emerges that can surprise and innovate”, says Carvalho. “But it won’t stop being round or having a soft material, whether it’s rubber or a synthetic compound.”

The use of recycled PET bottles is among the alternatives for a composition that is less aggressive to the environment. Continental introduced this solution in April.

According to the brand, the material replaces polyester in the housing composition. A set of passenger car tires would use about 40 recycled bottles. By 2050, the company intends to use only sustainable compounds in the manufacture of its products.

With the ESG (environmental, social and governance) agenda driving investment, companies are more concerned about the impact of tires on the environment.

In Brazil, Anip (National Association of the Tire Industry) estimates that more than 100 million unserviceable carcasses were correctly disposed of through Reciclanip, which manages reverse logistics.

But the companies’ intention is to produce items that last longer and allow longer life cycles. Michelin claims Uptis technology will prevent 200 million tires from being discarded a year worldwide, while Pirelli says Seal Inside technology reduces the need for puncture disposal. There is an open space for evolution, and only the shape of the tires should not change.