That "Hit the Streets" is an exaggeration, the actual quote from the article on timeline:
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the company said they were on track for tires to reach the market by 2024.
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I am an engineer working in the tire industry (throwaway is needed here). The Michelin "Tweel" IP was actually acquired when Michelin bought BF Goodrich 31 years ago. Goodrich developed the concept as a replacement for compact spare tires, doing the initial R&D in the 1980s. Every 3--5 years Michelin has a press release like this, and the technology is always 3--5 years away from release. Currently the US DOT and it's equivalents abroad are still in the rulemaking phase regarding airfree technologies, so there's that, too.
i would love to see this or a similar technology for electric scooters. the tubes seem to reliably pop every dozen or so rides, and the current alternative solid/no-flat tires really compromise on ride quality and handling. larger wheels (they're usually in the 7-9" range) would help too, but there's probably a practical limit to how big the wheels can be, perhaps 12-15" without too much compromise (motor power and ergonomics being two limiting factors).
The unagi scooter has them[1]. In all honesty, they're garbage for NYC. They are somewhat of a hard plastic, and do not provide the kind of give that your want for roads which have imperfections. It saddens me that peoples first impression of micro mobility is this piece of junk that makes riding scarier and more dangerous than it would be with air tires.
It's likely possible to make a good airless tire, but I bet the materials would be expensive and I'm not sure what it's lifetime would be. Air tube tires remain the best option for micro mobility options.
yah, i'm skeptical that a solid (rubber/plastic) tire can provide good suspension and handling performance cheaply across a wide variety of road hazards, in comparison to an air tire. that's why i think bigger tires (and thicker tubes) is probably the way to go, but perhaps advances in materials/manufacturing will make all kinds of tires incrementally better.
> The Michelin "Tweel" IP was actually acquired when Michelin bought BF Goodrich 31 years ago.
If thw core patent is 31 years old then that means it's been in the public domain for 11 years. Anyone should be able to make a variation thereof at this point - steering clear of other derivative patents of coarse.
What are the reasons for it constantly being 3-5 years away? Technology? Regulations? Both? Manufacturers not thinking the public will understand tradeoffs and unwilling to take the risk and explain this to them? Can it at least work as a spare tire?
I can't answer your question exactly, but I can add that regular air tires have advanced tremendously in the last 30 years. It's also a moving target for these airless ones to compete against.
Thank you for perspective; I felt strongly that I've seen excited articles like this several times in the last decade or more. I was starting to wonder if I'm missing some changes or concepts that would explain the discrepancy :)
The video looked like a fancy PR piece and that's it. Sad that this tech has been shelved for 31 years. Maybe there isn't a viable go to market strategy.
There have been a number of reports of components of rubber tiers being harmful to humans[1] or the broader environment[2] beyond the waste issue, would be interesting to know if these manage to improve on that.
If it's biodegradable, that would help. Only what remains of the tires ends up in landfills/recycled. The rest is a major contributor to microplastics in our oceans. The tires don't just erode into nothing. Those particles (mixed with particles from the road service) become dust that ends up in sewers when it rains, which drain to rivers, which drain to oceans. By the time the tire is used up, we're talking a sizable amount of material. Vulcanized rubber is nasty; it doesn't really break down (that is the whole point of vulcanizing) that easily and is also toxic.
Has anyone done analysis on microplastics to figure out what percentage are from vulcanized rubber? It's probably a high percentage, but would be nice to have an actual scientific study on the figure.
This is one of the many reasons I'm firmly in the "urbanization or bust" camp. Rail-based infrastructure is lower-carbon, doesn't require batteries, and doesn't require tires, but it's only practical in high-density cities. Streetcar suburbs represent a reasonable minimum.
I don't know enough about chemical engineering, but there was a tyre recycling company called Pyrolyx AG that went bankrupt last year. I think they were doing something along the lines of what you're talking about but they failed to commercialize and the pandemic accelerated their demise.
My car had runflats when I bought it, when it was time for new tires, I went with some high quality all seasons. My ride quality improved, my gas mileage went up and they brake / corner better. The risk of an unplugable flat is a small price to pay for that.
Run flat tires are expensive, heavy, and hard riding. On the other hand, they don't go flat. I recently had a flat in my VW and I missed having my old Mini's run flats. Sometimes you just aren't in a place where you want to change a tire.
I've always had conventional tires, but when my Kia Rondo was due for new ones a few years ago, my tire guy suggested the Bridgestone DriveGuard. I was skeptical because of everything I'd heard about run flats, but he said these were a big improvement. And he was right! They feel just like conventional tires.
Maybe a bit harder ride, but I had been in the habit of inflating my old tires 2-3 pounds more than the manufacturer recommendation. So I brought these back down to the recommended 32psi and they are just fine. And they proved their worth when I got to a job interview on time even after getting a flat - and when I went to the tire shop it was a free repair instead of a new tire.
It's common for aircraft and other heavy duty equipment's tires to be retreaded. Seems like a reasonable thing to do on passenger vehicles if it can be scaled.
It used to be done for passenger car tires. A quick search says one can still find recapped tires if determined. But why isn't it more common, when it was common about 40-50 years ago? Well, that time began to approach the time I spent as a mechanic, and the reason was cheap, imported tires that were starting to come out of Asian factories. I can sell you a retread, or you can have a brand new tire from some off-brand for about the same money, and guess which was chosen more often?
This link seems to line up with what I remember from 40 years ago:
It's also common for semis to shed retreads at highway speeds. Having hit one on the highway, no thanks. We don't need more highway missiles and debris, which is precisely what would happen if retreads were common on passenger vehicles.
This was the number one problem with retreads for the trucking industry, and most mechanics viewed retreads as cheap (the bad kind of cheap), low quality ways to keep trucks rolling, preferring new wherever possible.
Perhaps the tech has matured some, but I doubt it. You're still attempting to bond two different soft materials.
I haven't done too much long distance driving since COVID hit but I remember seeing shed retreads last time I was on the interstate. I always thought it was amazing that semis could get away with shedding them and driving away leaving at the least trash on the side of the road and at worst causing a dangerous accident.
Well, they don't really "get away" with shedding them. It's the equivalent of a blowout. Part of the reason they have such a bad reputation among semi mechanics.
yeah, that feels about right for all of the swerving required to avoid running over the retreads that have let go and now lay in the middle of the highways.
>Connected: Reports tread status and configuration, e.g. to inform the driver that he should change to a winter tire tread.
That sounds like everything that's terrible about printer ink but with the decimal moved once to the right.
I can imagine a world where your tires stop working because you had them re-treaded with a tread pattern or the OEM won't honor a warranty item because you didn't use an approved brand of retread.
Your printer running out of ink does not have an associated risk of death and injury. Tire wear does.
Existing air-filled tires are already "connected" on modern vehicles - pressure sensors that link to the vehicle's on-board diagnostics and inform the driver of low pressure, often before there's any other visible, audible, or mechanical indication that the tire has a leak.
Modern cars have tons of sensors but none of them are in the consumable parts such as tires[+]. It's important because it means you can use any consumables (gas, oil, coolant, washer liquid, tires) as long as they meet objective physical requirements the car expects.
If the tires provide enough traction and are of the correct size then any modern car will work with them fine. "Connected" tires sounds like there is a direct (as opposed to the car measuring the tire's shape in the TPMS from your example) information exchange between the tire and the car, something that does not happen now and appears to be susceptible to the same marketing practices printer manufacturers use.
[+] Some cars have "sensors" in the brake pads, which amounts to a wire loop inside the pad, which gets cut as the pad wears down, owners of these cars are not happy about this "feature".
>"Connected" tires sounds like there is a direct (as opposed to the car measuring the tire's shape in the TPMS from your example) information exchange between the tire and the car, something that does not happen now
Michelin sells a tire mounted TPMS, also available pre-installed.
Not for cars, though. There is probably a market for tire monitoring in mining equipment, which is probably not constructed with the same built-in systems that consumer cars have.
You are incorrect. Most modern cars have TPMS to tell you when a tire is losing air. There are two ways to do it. Either you use the same signals ABS uses to tell how fast each wheel is spinning and look at the tire which spins at a different speed.
The other way is to have actual pressure sensors inline with the valves that wirelessly communicate with a system in the car. This method has the upside of allowing you to see constant tire pressure values on all four tires at all times. The downside is that it is more expensive, it's something that must be managed when you get tires or wheels changed, the batteries run out, you often have to pair each wheel-sensor to the car separately so that it knows which sensor is which wheel...
I am not sure if you replied to the correct message but I did mention that modern cars have TPMS. If you are actually arguing against my description of the principles this system works on (monitoring the wheel shape through the rotation speed) then perhaps you should have not posted a link to sensors for such a system. I somehow don't see how a passive device can monitor any pressure least communicate wirelessly. But even if such system existed it would still have been mounted in the wheel, not in the tire on modern cars.
If I'm reading your posts correctly, you're saying that tire pressure sensors are not mounted in tires of common cars. This may be true in EU and other places where I think monitoring rotation rate of each wheel is typical; in USA, as far as I can tell, most tire pressure monitors are indeed wireless devices mounted inside the tires in connection with the valve stem. This is the case with my car, which is an American variant.
It might work similar to low pressure, where you see the wheel light up on the dashboard. Ofcourse the human part can make the decision on what to do about it, and if you want to replace tyres, how many at once.
Surely it saves a lot of rubber waste too? Like 90%+ of the rubber mass of a typical tire must be in the parts that never contact the road and therefore should be good forever?
Unfortunately not the case. Tires go through lots of heat and stress cycles. I think most of the heat a tire generates isn't from friction with the road, even. It's internal friction within the tire itself. The carcasses are made of wires/meshes/layers of aramids/steel/aluminum and aren't indestructible, even if durable.
And the rubber on the sidewalls gets degraded by sun/dirt/sand/etc, too.
True, true. But from the picture in the article, it sure looks like there's a heck of a lot less rubber overall in this tire— so regardless of what it's been historically, this is a step toward a tire that "consumes" way, way less rubber per X distance of driving, whether due to less rubber being in it overall, or it being able to be recharged with additional tread before being disposed of.
Tires where purchasing decisions are driven almost exclusively by cost per time or distance are routinely retreaded. But that does not describe the passenger car tire market.
Doesn't it? I mean, I get that some people want to try a different make/model of tire when replacing it for performance/noise/appearance, I've been one of those people at times.
But I also think there are plenty of people who get the tire that's available to them and reducing the cost per year of use would be welcome.
I will say that having an EV, the cost of tires really stands out. In 60K miles the only maintenance expenses I've had have been tires and a windshield. Even the ongoing cost of charging is basically invisible (plug in at home, free on the road), so tires have been about half the money I've put into it, it feels like.
I remember retreads being a thing you could buy for your car in the 1970s/80s. I remember local radio ads from retread shops. I haven't heard of passenger car retreads in decades though, so I don't think it's really done anymore.
In New Zealand you could get tyres retreaded decades ago, however it was banned for light vehicles, due to safety reasons I believe.
Truck and specialty tyres in NZ still get retreaded by a company called Bandag, and you sometimes see detached tread at the side of the road. I am guessing that retreads are only allowed for dual tyres on trailers, where if a tyre fails it isn’t catastrophic. I imagine they are not allowed for the critical front steering/braking tyres on the tractor unit.
It's only terrible because we've created a system that incentivizes it being made purposely terrible for profit. The idea that your tires can monitor their own wear should be a good thing.
I mean recyclable in a conventional sense the way most people understand it.
Energy cost is probably the single biggest obstacle for the technology I mentioned above. Renewable energy is changing this.
Most plastics will soon be a part of an efficient closed loop system. Regulations are driving some of this. However, the real driver is that these systems are incredibly profitable, and serve risk and resource management priorities as well.
I wouldn't be surprised if Amazon and others started accepting plastics and paper returns. Their consumption is massive and they already have a logistics closed loop in place.
Plastics are an incredible innovation and a valuable resource. Misinformation about their recyclability is a threat to their stewardship.
The technology may exist to recycle plastics, but at least where I live, there is No infrastructure for it to happen. So no, it isn’t recyclable in reality.
Can you point me to something that describes these closed loop systems? What you are saying sounds like a paid advertisement.
It is a company vision, not a product announcement, so as expected much of it is fuzzy and hypothetical, and it may or may not apply to this particular product.
But this part offers a clearer idea of what rechargeable means:
> The tread can be “recharged” using a 3D printer, which means that VISION can be adapted to motorists’ changing needs, for maximum comfort, safety and sustainability.
They also have an official page for this actual product line, which is called Uptis (Unique Puncture-Proof Tire System):
The FAQ on this latter page says stuff relevant to sustainability:
> Today’s level of rolling resistance is about the same as a zero-pressure (“run flat”) tire
...
> Uptis will have the same mileage of a standard tire.
I believe this is an important part of sustainability because if mileage were worse, you'd gain in one area (reduced waste) and lose in another (increased energy usage). So if mileage really is the same, that's a good thing.
I'm actually surprised that I've never seen a tire with some kind of closed-cell super lightweight foam, some kind of aerogel maybe. I suppose the problem in that case is that you can't spread heat throughout the whole interior.
Which makes me wonder, how do they radiate heat on this Michelin? Does it stick around the outer surface and that's it? Do the 'spokes' bear it away somehow?
In the off-road motorcycle industry there are these tubes called mousse bibs. I run them on all my bikes. They do replace the inner tubes, not the tires themselves. But they work great and are the best anti-flat solution out there. They sound similar to what you’re talking about. Michelin makes them too.
I have something similar for my mountain bike, CushCore. They don't replace inner tubes (tubeless setup) but they do add a lot of protection, dampening and deflection.
I haven't used it, and most serious track rats have a separate data system so the track connect features are potentially redundant, but I assume that it's an MVP of what a consumer product might look like in the future.
The embedded video seems to show that you can 3d-print on top of an existing tire, which would let you "recharge" for a certain number of km. It's also more sustainable that way.
Hmmm, I doubt about the actual duration of something just 3D printed over, in the sense of adhesion, I remember the process to join (rubber based) watertight expansion joints and it involved (after preparation of surfaces and application of adhesive) some half hour pressed into a heated aluminium cast. (and the procedure is similar AFAIK for retreading tyres currently in use)
On the other hand, they were common in Italy in the '70's and '80's, there were truck tyres that instead of being re-treaded with the "hot" process above were thinned and grooved on a sort of lathe and then a monolithic external "ring" that included the tread on the outside and matching grooves inside was applied, when the tyre was inflated the grooves and the pression made the two stay together (until the tyre was punctured, it was not so rare that you could find on roads these outer rings lost by some truck that had a flat wheel).
#3 you'll end up paying $200/tire plus a monthly fee to use them. Upgrade to premium and get unlimited mileage plus insights on how you can be a better driver!
I guess as part of this subscription plan they'll call you forty five times a day trying to get you to upgrade the warranty on the tires. At least there are a lot of qualified contractors they can outsource that to!
Even if these tires aren't good enough for the snobs who want everything to be silent and handle perfectly they'll be great for trailers, yard trucks and other rarely used vehicles that rack up few miles and run run old-ish tires (which tend to be more plagued by slow leaks and whatnot) but still need to go highway speed.
Road noise isn't just a driver aesthetic preference, it's a form of pollution that has direct impacts on human and animal health.
I could still be convinced that the sustainability or safety (from fewer blowouts) gains of these would outweigh that, but it's important to consider beings outside of the auto cabin.
Rubber material properties (hardness basically) is a rounding error compared to tread design in terms of road noise and the dominant factor in terms of how long it takes the tire to wear down.
Do you have any sources to back that up? All the literature I find is pointing to tire vibrations, which I would guess is a mix of material properties, tread design, and more.
Not true absolutely. The rubber hardness is highly temperature dependent, and is modified by tinkering with your glass transition temperature. Winter tires have a lower glass transition temperature (are softer at lower temperatures), and as a result will wear down much, much faster in summer.
Nothing snobbish about wanting silent tires. Tires are one of the main factors for road noise, and road noise causes adverse health effects and death on a large scale.
The air pollution near a highway may be measurable, but it is not immediately visible. The road noise, on the other hand, is overwhelming as soon as you step outside. For sure road noise drives more of the blight on housing value near high speed highways.
Any noise a normal-ish passenger car is of no consequence compared to the noise of heavy trucks and motorcycles. You don't even notice it.
It's only "blighted" because the people who self select to live beside a highway tend not to be the ones who care a ton about making their residence look nice from the street (manicured lawn, nice siding, sealed driveway, etc, etc) so the prices stay cheap, the rents stay low and the cycle continues.
“Houses nearby highways are low value because the owners are too lazy to manicure their lawns” is an explanation I don’t buy one bit. It’s too “just so” for my tastes, and it also contradicts my own personal experience of having my house value go up despite us purposefully killing the yard. Home values change for a lot of reasons outside the owners control; blaming it on the owners for not caring sufficiently about curb appeal doesn’t hold water.
A more likely explanation is that living near a highway sucks. Very few people want to hear traffic noise from their back yard, let alone smell exhaust fumes while trying to grill outside. People who can afford to will pay a premium for a quiet and peaceful backyard, and houses with traffic noise close to them will command a lower price to compensate for the lowered quality of life. The fact that we see a similar effect near airport runways is a supporting data point.
I would in fact argue that you’ve got causation backwards. The curb appeal of houses near the highway is low because the home values are low. The people who live there are aware that nothing they can do will push the home value up because of the highway, or they lack the time and resources to focus on a manicured lawn.
I suspect a significant causation could be that living near a highway is low status, and having a beautifully manicured lawn is often about trying to signal high status. Why bother with a high status lawn on a low status property?
>“Houses nearby highways are low value because the owners are too lazy to manicure their lawns”
Well you're in luck because if you re-read my comment without the intent of building a strawman you'll see that that's not my explanation. My explanation is more or less "selection bias" I tried to offer some examples as to the mechanisms of such selection but you read right past them.
>A more likely explanation is that living near a highway sucks.
I like it specifically because people "who are willing to pay a premium for a quiet and peaceful back yard" do not elect to live in places like this if they have the option of paying that premium. This means I am free to use power tools into the evening, the business across the street is free to use heavy equipment in the morning, my neighbors are free to play loud music, have barking dogs, yell at their kids, etc. etc. etc. Things like not having to be anal about cutting our grass and keeping our houses nice follow quite naturally from that. If you don't care about other people's business in a similar manner the cost savings from living in this environment are tempting.
>The fact that we see a similar effect near airport runways is a supporting data point.
Yes, people who care about noise avoid those too. What's your point.
>I would in fact argue that you’ve got causation backwards. The curb appeal of houses near the highway is low because the home values are low
Values are low because a subset of people don't want to live here. Selection bias applies to both groups increasing the disparity.
You are foolishly projecting your opinions onto everyone. Some people simply don't care about the noise. They cluster where it is noisy because why would they pay more to avoid something they don't place a high value on avoiding. Are these people a minority when you look at the population overall? Probably. Are these neighborhoods composed of many people who simply tolerate noise because they have no other rational option. You call this blight but I call this a reflection of our priorities.
I disagree. The difference that I and many other people noticed on city streets during the initial COVID lockdowns was enormous. Cities aren’t loud places, the continuous white noise from passing passenger vehicles is the loud part.
60 km/h traffic is 10 times louder than people having a conversation.
Even 30 km/h is far from silent. Especially around intersections and traffic lights. And when you have trucks or buses accelerating it almost doesn't matter that a typical small car doesn't make that much noise at that speed anymore.
Death on a large scale? This is the first time I’m hearing of this and I’d be interested to read more. Do you happen to have a study or something I can read?
I'm curious, how do we differentiate dying from noise pollution because you live close to a major throughway vs dying from the regular pollution that you're breathing in because you live close to a major throughway?
You try to control for statistical variables like pollution, occupation, and personal habits. I don't know anything about medical statistics, so I'm just accepting the conclusions of the road noise research.
This paper should be helpful if you want to dig into the methodology one can use.
Michelin has been selling these under the "Tweel" name[0] for skid steers, commercial lawn mowers, and other mid-sized wheeled equipment for several years now. Supposedly, they improve the handling and ride of the equipment since the Tweel's internal structure flexes more than an air-filled tire and therefore adds more of a suspension to the tractor.
I was expecting yet another minor convenience that doubled the ecological footprint of a thing. But it looks like reducing impact was actually a goal here. Pretty awesome.
They're trying to spin it as reducing the environmental impact, but the actual details in the article seem iffy. Glass fibre reinforced plastic is basically non-recyclable and they only have some vague ambition to make them out of something that is at some unspecified point in the future.
Yeah greenwashing is a thing and even a lot of stuff that genuinely well-intentioned can have externalities that outweigh the benefit. But at least it looks like they're trying.
Yes, but that's a known issue that has nothing to do with it being airless.
Back when I used to go off-roading a lot it was common behavior to leave a lot of space between you and the truck ahead when you got back onto a paved road. The open tread pattern of offroad tires picks up lots of small rocks and sends them flying back at highway speed. Not good for the windshield on the following vehicle.
I live on a gravel road now. You learn not to follow other vehicles too closely!
> Puncture-proof tires have been an intriguing concept for many years. Tire maker, Michelin, has been working on it since 2005 and after more than a decade of work, it is now closer to reality.
That is false. Tires like this are nothing hew; they have been around for over 100 years. They are useful in niche applications, like earth-moving machinery and whatnot.
Other than that, airless tires are rubbish and will not displace pneumatic tires.
I have airless tires on my bicycle. They are slightly firmer than regular tires, but the trade-off for knowing I will literally never get a puncture is more than worth it.
Short of obviously poor quality components, materials and builds, almost nothing is objectively rubbish in cycling, because cycling is about experimentation and personal choices, which can be all over the place.
A lot of cycling is recreational and light commuting, and so performance factors do not matter.
Airless tires are certainly right for someone who abhors punctures and wants to avoid them at all costs. Factors like efficiency, weight or ride quality don't necessarily matter his or her use case, or even if they somewhat do, they are overridden by the abhorrence of having to pull off to the side and deal with a flat.
Yet, even though cycling is the one sphere where airless tires could have a chance, is is overwhelmingly dominated by pneumatics, just like motorism.
I don't think you will see anyone place well in a road cycling competition, if they bring airless tires. But, well, so what? A lot of the bicycle tech is driven from the top down by the competitive sport; and maybe that results in certain technical choices being promulgated at the entry retail level that are not necessarily relevant to every user.
These remind me of the Tannus[1] solid bike tyres that have been around for (...guessing from memory...) about a decade now.
I think last time I looked that them the rolling resistance was a little more than I'd like on my "fun" bikes but for commuting that they look great option.
I think my personal preference for a "ride flat" system would be for a tubeless tyre, sealant and an insert like Tannus' Armour Tubeless (...or tubs I guess)
I suspect the production version will have a covering on the sidewall for that and to reduce aerodynamic drag. It won’t be structural like current tires but I think the “wall-free” design you see now is Just prototype marketing.
Tires were hemp-reinfoced plastic, then steel-reinforced plastic, they are now actually fiberglass-reinforced plastic.
It doesn't matter. So long as elasticity is provided not by gas compression, but solid material compression/tension, that solid material will deteriorate fast.
Downvote me all you want, but this idea won't fly. It can't compete with regular tires at anything above 20mph.
> 21. What will happen if some small stones or mud or snow get in between the structure of Uptis?
> The objective during the development of the commercial product is to test Uptis in all of these situations. Some preliminary tests show that stones, mud or ice/snow will not stay inside the Uptis structure.
Obviously preliminary tests aren't anywhere near enough to prove it's a nonissue, though.
It wouldn't be too crazy of an engineering trick to make the pores flex in a manner that causes them to crap out anything that's clogging them as the tire goes around.
Alloy wheels don't need to flex, though. If a rock wedges into nooks and crannies of this, perhaps it could mess up the performance. And perhaps it could cause damage since you'd have a harder material (rock) rubbing against a softer one (rubbery airless tire stuff).
Looks like a complete pass through from one side to the other so washing them should remove most of that. Rocks might even fall out as the tyre rotates.
This website is funny in the EU. I have to scroll to the bottom of the disclosure before it lets me press “reject all”, as if I would care about exactly what I’m rejecting.
It is perhaps useful to consider the entirety of the disclosure, however, in that it would let you know that by pressing "reject all", it appears that you are allowing all their listed purposes: they claim legitimate interest for every purpose they list. Reading further, after scrolling through one list of around 700 partners, you would also find a second list of what appears to be around 700 other partners, with, it appears, likely around 300-400 legitimate interest switches, all defaulting to on.
That depends on jurisdiction. In the U.S. there are plenty of sites that opt you in, and either allow you to reject or don't but link to their privacy policy (which then might say "we don't care about your privacy").
That would be a separate engineering problem. If it needs to be a different rubber or polymer compound then there's the bonding issue. They would need to have an air outlet to avoid pressure differential, but that then means one needs to figure out how to have a cheap waterproof valve because it probably is not desirable to have stagnant water inside.
This seems like an excellent idea for a spare tire, since those usually only lie around for a long time in the boot, and when they do get used it's expected that they don't perform exactly as the regular tires.
For some reason though, it seems like a lot of car manufacturers are moving away from spare tires to things like "car puncture kits" that fill your tire with foam or something. If the recycling of tires was abysmal before, something like that seems like it would make it even worse.
Anyone know the lifetime of the threads or tire? How often will they have to be replaced? So if it's the same it's not really much of a improvement. Just for the luxury of being "airfree". There will be some negative aspects or tradeoffs to be made with the tire? Companies are in it to make money and surely they won't make a new time that is 100x lasting than the current because that will be a losing proposition in their view.
In the concept video it’s shown that a 3D printer can print layers on top of the tyre. I think this is what they meant by rechargeable - the ability to “fix” the tyres.
And you've found the problem. Michilin is trying to compete with Firestone to sell the next set of $1k tires you put on your expensive car. They're (mostly) not competing with Deestone and Linglong to produce the cheapest tire for your beater car. The people buying the former don't buy retreads. But they might if you find a way to re-spin the same fundamental idea as something that isn't low-end. And if you're the first to figure out how to sell that product to those people you can make boatloads of money while everyone else plays catch up.
Contact patch and rubber compound being close to constant when compared to a pneumatic tire the mileage impact would primarily depend on weight. I don't think it will be much of an impact since Michilin is unlikely to make a very heavy tire as that would have bad NVH characteristics which don't jive at the high end and reading between the lines of the press release stuff seems to indicate that's where they're targeting.
Adjusting inflation pressure is a feature. I run my tires higher than the vehicle recommendation but still below the sidewall limit for improved fuel economy. Airing down for sand is a thing too.
That will likely increase wear and decrease traction. What's happening is that the contact patch is getting narrower and the sides of the tread aren't helping support the weight as much.
I worked in a tire shop, and chronic overinflation caused tires to go bald in the center of the tread while the sides had tread left. Have to replace them more often then.
I understand the dynamics. My interests and driving style rank fuel economy over handling. I've never had tires wear out middle-first. I generally get edge wear first or even wear across the tread.
I just got a set of tires replaced under tread life warranty because they wore out edge first. The tire shop set the pressure higher than recommended and actually a little higher than I usually set it myself.
Airless tires will still wear out though. That’s the nature of friction with the road. The important one is: how much more durable are these compared to your normal rubber ones?
Per the video, their plan is to 3D print additional sustainable tread on demand and/or switch you over to snow tires if you need them using 3D printing techniques while you have a snack (apparently)
They can be re-belted like a semi truck tire, with a sacrificial wear layer on top of an airless support structure. Obviously they will still consume the rubber that wears down, but most of the tire will be reused rather than disposed of.
Handling and NVH tradeoffs. You can reduce tire pressure to combat these but a more substantially built tire will succumb to heat related early failure more easily if you do that. Also money. Tires with more stuff in them and more exotic stuff in them are more expensive because that directly translates to more manufacturing steps.
My bicycle tires are kevlar (I think) reinforced for puncture resistance. For me it was absolutely worth the cost, given how often I had been getting punctures before that: on a roughly 12-18 minute cycle commute, I went from one every month or so with normal tires to no puncture ever until the tire itself wore out.
Kevlar-reinforced tyres exist, they’re used on off-road vehicle. I expect they don’t protect much against the sort of very thin puncture you’d find on a standard road because there’s simply too much pressure being applied when driving a car over a nail/screw.
I don’t think carbon fibre would be of any use here, it’s not super strong against high transversal forces AFAIK. It’d mostly be useful for sidewall rigidity (and I’d be surprised if it didn’t already exist).
You can buy airless inserts for bikes, as well as airless tires. These are not used in higher performance applications. In performance road, gravel, and mountain bikes you find tubeless tires that use sealant instead of airless inserts.
In 'The Wide Lens' by Ron Adner, he uses Michelin's run-flat tire initiative (PAX) to show how brilliant innovations can fall flat (sorry, couldn't resist) if the entire ecosystem / supply chain is not enabled.
In the case of PAX, the service stations (75% of the market is replacement) were not ready.
Hopefully, Michelin has the full ecosystem enabled in this case, as this seems promising.
The sad part for Michelin is that not much later BMW started using run-flat tires on all their cars. So it was really just a value-chain issue, not a lack of demand or bad timing.
> In several lawsuits and on some Web sites, consumers have complained about the difficulty of finding shops with the equipment to work on PAX; they also cite excessive tire wear and replacement costs as high as $1,600 for four tires.
