This may be of interest to Prius Prime owners who are concerned about the Prime not having a spare tire. According to an article in the June 15 edition of The Economist, Michelin is working with GM to offer in the future a new kind of tire system on the Chevy Bolt EV. The tire is called UPTIS for "unique puncture-proof tire system" and is different from “run-flat” tires which use reinforced sidewalls to remain upright if punctured and must be driven at reduced speeds for a limited distance only. The UPTIS uses an integrated wheel and tire that comes in one piece. The wheel part consists of an aluminum assembly in the center with spokes made from a new composite material described as “resin-embedded fibreglass”. The spokes are fitted with a conventional-looking tread around the outside of the wheel. When the tread wears out, Michelin and GM hope to use a 3D printer to create a new outer shell for the tire. These tires resemble the small, airless rubber-spoked wheels already used on golf carts, lawnmowers and some all-terrain vehicles. However, the UPTIS is designed to take the greater weight of a car and cope with high-speed driving.
My question is what do they mean by "connected"? These days that usually means some sort of "smart" electronic feature
Similar tires have been available for small yard equipment like yard tractors and riding mowers for many years, but they weren't cheap even for such small size tires. For a passenger cars, "integrated wheel and tire that comes in one piece" means it must be even more expensive than conventional tires and wheels together. Even if it has much longer tread life, the tread must eventually wear off, then I guess you have to purchase a brand new "integrated wheel and tire that comes in one piece" again, for what cost??? Edit: Oh, I didn't read the part about "When the tread wears out, Michelin and GM hope to use a 3D printer to create a new outer shell for the tire." But still... for what cost???
Existing tires have great variability in tread life from 30K to 90K. If it really last 90K, for me that maybe close to a life time. Of course, with conventional tires, I have never be able to extract the max tread life tires warrant anyway. Thus I should not expect any better from the new flatless tires either?
when will these be available? us pip owners have no spare either. i will need new tires around 2024 or so, are they quiet and smooth?
If they'd put the spokes at a slight angle, it'd throw a real nice sideways rooster tail going through water. It'd keep drivers out of your blind spot.
The Economist story says that the UPTIS tire is more expensive but because it is not pneumatic, there is no need for the cost of air pressure sensors (which are expensive). Also, because the tire is not pneumatic, uneven wear caused by over- and under-inflation is not an issue. All I know is what I read in the article, and I'd expect that there are going to be issues which were not discussed. For example, the article makes no mention of the effect of these tires on fuel efficiency. It's an interesting and novel idea which is still a few years away from being "ready for prime time." But still . . .
Is this the same as a Tweel or is this different? The video shows slow rolling over potholes, but how do these handle in a quick turn? Not that I do high speed turns in my Prius, but in an emergency situation, you just never know.
This is the next generation of the Tweel. There is another thread about this somewhere. Noise was an issue with past models. Dirt and rocks could also get into the spokes, throwing them out of balance. That may also be true with snow and ice. A sidewall membrane seems to obvious fix, but then the spokes can't be inspected.
