Airless tires made with NASA tech could end punctures and rubber waste

As SMART Tire co-founder Brian Yennie tells IE in an interview, NASA's shape memory alloy (SMA) technology built for its rovers could have a great benefit here on Earth, making an inherently unsustainable industry sustainable in one fell swoop.

According to SMART Tire, 75 percent of the tire industry's revenue comes from replacement tires, with the U.S. producing roughly 246 million rubber waste tires per year. SMART Tire's products would help do away with this waste as they are built to last, using memory metals designed to resist the wear and tear of harsh space conditions.

The company's two founders, Brian Yennie and Earl Cole, believe their new tires will change the $250 billion tire industry, which, they argue, is long overdue for disruption.

We spoke with co-founder Brian Yennie to catch up on what SMART Tire has been up to since we wrote about them last year, and what they are doing to compete with the likes of Michelin and GM in a bid to reach their ambitious $55 million valuation cap goal.

The following conversation has been lightly edited for clarity and flow.

Interesting Engineering: Will the technology used by SMART Tire make punctures a thing of the past?

Brian Yennie: "Yes! Without pressurized air inside your tires, punctures are no longer a concern. Even large tears won't slow these tires down: you could stick a kitchen knife right through and keep on riding, because it's not going to affect the structural integrity of the tire. The really special thing we're doing, though, is making an airless tire that is also fuel efficient, able to carry heavy loads, and gives a smooth, quiet ride. The reason you don't see airless tires on the road is because nothing on the market passes even two of those criteria, let alone all three."

IE: How will it improve road safety?

"For starters, there will be no tire blowouts, or underinflated tires. Over 20% of roadside emergencies involve a tire issue, and the vast majority of those are due to a loss of pressure or improper inflation. Beyond that, SMART tires have a very specific advantage: a longer, flatter contact patch. This is the portion of the tire that is in contact with the road, and in a conventional tire it's more of an oval most of the time. Just look at the uneven wear on your tires, which you have to regularly rotate. It's a subtle thing, but tires making even contact with the road is a huge deal for traction, safety, and tire life."

IE: How do you plan to roll out SMART's technology to customers? Will it be used on bikes first before eventually making its way to larger vehicles?

"Our first product will be our METL bicycle tire. Cyclists are passionate about new technology, and this is a great way to put something in consumers' hands early in our journey. Around this same time, we plan to also launch a version for electric scooter fleets. These operators spend an incredible amount of money on repairs: over $75/month on average for a $400 scooter. Their customers hate solid tires, so they're stuck between a rock and a hard place either bleeding money or upsetting riders. Shared micromobility is big business: $300B to $500B by 2030 according to McKinsey, and they need better tires.

"Shared micromobility is big business ... and they need better tires."

"A lot of people ask about automotive [tires] (who wouldn't want these on their car?), and the short answer is: yes, but it's a few years away. As you can imagine, DoT regulations and testing requirements are extremely in-depth, especially for something different than the status quo. Ultimately the timing will be good: electric vehicles have major problems with tire wear and higher vehicle weight: both areas where we excel.

"Beyond that, there are some really interesting niche applications (mining, agriculture, offroad, military) but the one that really stands out is aerospace. Commercial aircraft use extremely heavy and high-pressure tires. Replacing them with something safer and lighter is a no-brainer (and will save a lot of jet fuel someday).

"Of course we're also developing lunar tires for Project Artemis, the original space application. That means SMART tires on the next "moon buggy" driving around the surface of the Moon."

IE: How involved is NASA in the process of helping build your technology? Can you tell us anything about what it's like to work with NASA?

"We work with NASA by licensing their patents, and through a public/private partnership agreement called a Space Act Agreement. On the one hand, NASA is a large government entity, and there is a bit of a learning curve. They can't just pick a private company and endorse you, or operate the same way that a corporate partner would. You need to understand regulations, how the licensing process works, and how to interact with the U.S. Government in general.

"[NASA] are simply the best in the world at modeling these materials, hands down."

"Now, the good part. There's only one NASA. Under our Space Agreement titled "Shape Memory Alloy Modeling and Development", they primarily assist us with computer modeling and optimization of our SMA tires. They are simply the best in the world at modeling these materials, hands down. Our lab is located in Akron, Ohio about 40 minutes from NASA Glenn Research Center (Cleveland) where we periodically get to go on-site. Not everyone at NASA is a literal rocket scientist, but the expression is apt, as they do employ many of the top scientists and researchers in the world."

IE: What do you say to people who think we shouldn't be investing in space technology?

"I'd say that space technology is just technology. Stories about eccentric billionaires or out-of-control budgets are headline grabbers, but the majority of work in this area is valuable. From satellites that monitor the weather or provide global communications, to pushing the limits of energy storage, growing plants under extreme conditions, or better tires, space technology is notorious for contributing to terrestrial applications. We put solar panels on a satellite in 1958. Now anyone can put them on their roof. So, the payback is not always immediate, but over time it's significant. My one caveat is that we need to continue to support public institutions like NASA, and not just rely on the Elon Musks and Jeff Bezos' of the world to take the reins. There's room for both."

IE: Finally, how have you furthered your technology in the past year?

"In the past year, we've reduced material costs by over 85% from the first bicycle prototype, integrated a lightweight casing, added replaceable rubber treads ("retreads"), and developed a continuous manufacturing process for the tires. Compared to last year, we've gone from proof-of-concept prototype to final tweaks before going to market. We also redesigned NASA's spring tire to meet much higher requirements than ever before for the Moon."