Airless tyres are on a roll

However, in an industry first, Goodyear has developed a non-pneumatic tyre (NPT) and wheel assembly for fitment to ‘Olli’ autonomous public transport vehicles operated by the Jacksonville Transportation Authority (JTA) in Florida, USA.

Olli is produced by Local Motors and, when launched, was the world’s first co-created, autonomous, electric vehicle; and is manufactured using 3D-printing technology.

For the past three years, Goodyear and Local Motors have tested an Olli shuttle, fitted with Goodyear’s NPTs. Now the project is moving into daily use by commuters, in a Test and Learn phase.

The urban transportation environment provides an ideal testing scenario for this alternative tyre architecture, given its lower speed and less-variable travel paths.

Goodyear and Local Motors will gather real-world data from the JTA, looking for viewpoints on ride comfort, noise and other variables.

“As mobility evolves…alternative airless architectures are ideal, particularly in the emerging autonomous transportation environment,” said Michael Rachita, Goodyear’s senior program manager, non-pneumatic tires.

“This is an important milestone as we look to advance mobility today and as we look to introduce the first completely sustainable and maintenance-free tyres by the end of the decade,” Mr Rachita said.

JTA CEO Nathaniel P Ford Snr said: “This collaboration is another example of how Jacksonville is leading the public transportation industry in developing AV mobility solutions.

“Testing with best-in-class software and technology partners is enabling the JTA to lead globally in readiness for the use of autonomous platforms in an urban environment.”

Local Motors President Vikrant Aggarwal said: “Autonomous vehicles, like Olli, need to decrease maintenance costs and perform reliably.

“Goodyear’s non-pneumatic tires are positioned to give maintenance teams less to worry about while giving passengers a quiet, consistent ride.”

The blindingly-obvious attraction of an airless tyre is its puncture-proof design: no air means no punctures. Also, there’s no need for pressure maintenance.

Michelin’s Tweel NPT range is the best known airless tyre initiative in the off-road-equipment market and Michelin expects to launch its passenger-car NPT in 2024. The Tweel has radially-disposed blade-shaped ‘spokes’ in pairs, but some other brands have various geometric shapes to connect the hub with the circumferential tread band.

All major tyre companies are heavily invested in NPT technology and have tyres at various stages of development. To date, the most common applications are in low-speed vehicles, from bicycles to earth-movers.

Polaris ATVs can roll on optional Terrainarmor airless composite tyres and these were derived from military NPTs developed for the US Humvee military vehicle.

At this year’s Brisbane Truck Show, Bridgestone showed its NPT semi-trailer concept tyre, but was quite tight-lipped about it and the display tyre was fitted with a red band that effectively blocked any view of its structure. However, we managed to find a photo of the interior that shows a resemblance to the Michelin ‘spoked’ design.

At this stage of development it would seem that NPTs for heavy vehicles travelling at road speeds are some years away, but you never know. We’ll keep up to date with NPT issues.