Have you ever heard of the SMART Tire Company? Forged in the unforgiving crucible of 2020, the company secured a federal Space Act Agreement with NASA to bring its fascinating shape memory alloy tyre technology to the consumer market.
It all started when tyre inventors Santo Padula and Colin Creager at the NASA Glenn Research Center worked to solve the problem of plastic deformation in Mars Rover tyres. They determined that a shape memory alloy called NiTinol would effectively solve that problem, while also lasting an incredibly long time with relatively little wear. Their creation was an airless metal tyre that can continually return to its original shape, with the strength of titanium. NEAT.
With its light weight and durability, naturally, thoughts turned to other potential applications for these tyres. That, friends, is when the SMART Tire Company was born, in cooperation with the NASA Glenn Research Center. Consumer bicycle tyres will come first, but if all goes according to plan, tyres for all kinds of automotive and aerospace applications will follow. If you want to know more, watch the video for a detailed breakdown of what NiTinol is and how it works, including this tyre application. It’s six minutes, and worth every second of your time, because it’s super cool.
The production tyre is called METL, which is short for Martensite Elasticised Tubular Loading. According to SMART’s FAQ, that’s “a very hard form of steel crystalline structure. When a shape memory alloy is in martensite form at lower temperatures, the metal can easily be deformed into any shape. When heat-treated a certain way, the martensite reverts to austenite, and the material recovers its original shape, giving it super-elastic properties. We designed this in tubular form for bicycle tyres.”
If you’re concerned about grip with metal tyres, all the Earth-bound tyres will also feature a long-lasting rubber tread made out of a compound called Polyurethanium™. According to the company, METL tyres should last the life of your bicycle, and probably have similar longevity in future vehicle applications as well. You’ll need to retread them occasionally, but the upshot is that there won’t be anywhere near as much tyre waste in the world if SMART Tires eventually sell in volume.
That’s an admirable goal in terms of environmental consciousness, but it’s also going to take time. For one thing, it’s still in the early stages. METL bicycle tyres aren’t available to buy as of March 2021. For another, they’ll be priced at a premium at first. Like most new technologies, they should get more affordable as time wears on but that automatically means fewer early adopters.
Presumably, a similar model will follow if and when tyres for additional vehicle types—including hopefully motorcycles—are introduced in the future. However, as a best-case scenario, we’re looking at years before that happens, if ever.
Still, airless, lightweight tyres that just require a retread every once in a while sound ideal for plenty of everyday street and off-road motorcycle applications. It’s not clear yet how well these would do in a track setting, but we look forward to seeing this idea evolve over time.