Tweel – Airless Wheel | Hacker News Reader

Tweel – Airless Wheel

en.wikipedia.org

40 pointsvinchuco16 comments

Love the comment about water evacuation through holes reducing hydroplaning.

I'd love to know what's holding these back. Perhaps it's just a higher cost:MTBF ratio, and one day it will surpass regular tyres. Perhaps they're really truly better, but pneumatic tyres are just Good Enough. Perhaps there's a fundamental flaw in the idea that only experts can see. Probably we'll never know.

They have a terrible NVH (noise, vibration, and harshness) profile. The deformation of the tire in motion produces significantly more noise than a traditional tire due to the larger amount of material and greater stiffness required for the support structure. These high levels of "tire noise" are the main hold up for consumer applications as the tweel has caught on in low-speed applications when durability outweighs cost considerations.

Wasn't there a lot of concern awhile back about electric cars being too silent, and therefore dangerous to pedestrians, etc who can't hear them coming?

Maybe noisy wheels are a better solution than playing artificial engine noises through loudspeakers.

They have the same problem, which is that electric cars are only silent at low speeds. At high speeds, the tires already make plenty of noise. The problem with electric cars being quiet at low speeds is that's when you're most likely to encounter pedestrians. But that's just when these tires would make the least noise, so they probably won't help.

They also used to put fake horses out in front horseless carriages. This will pass.

I didn't believe you, so I googled it.

Not convinced that it was ever produced, but still:

http://content.time.com/time/specials/2007/article/0,28804,1...

The last time I read about these the main problems were replacement cost and ride comfort. It appears that Michelin already offers them in applications where ride comfort isn't an issue, such as riding mowers and skid-steer loaders.[0]

[0]:http://www.michelintweel.com/

The fundamental flaw of the twheel is well known: something gets stuck in the spokes (mud, gravel, etc) and they go out of balance. At highway speeds: best case scenario is annoying vibration; worst case scenario is dangerous loss of traction and/or broken suspension components.

Michelin currently has a factory that makes these for low speed industrial applications (e.g. a skid loader). We probably won't see them on dealership lots any time soon.

Can't you just cover the wheel? Certainly I would think the sides would be easy to cover; the tread itself might be more difficult, but unless I'm missing something, having the tread be open is not a required part of this design.

Basically I'm imagining something that looks like a regular tire, but inside has the tweel. In addition to the tweel's benefits, you also don't have anyone even notice you're using something different.

Perhaps something similar to spoke-less bicycle wheels, that have a cover? I don't seem them very often, but they seem to be standard on bikes in indoor track races, e.g., Summer Olympics.

From my prior reading, there are heat issues at speed and when they tested at highway speeds (if I recall correctly, on an Audi) there was alarming vibration past ~50mph.

I would buy these very quick of they entered the market.

This looks great, and has some very compelling benefits. I'd be curious to know what their performance is likewhen caked in road ice like we get here in the northeast after a few rounds of snow clearing and melt and freeze cycles (the prototype on the Wikipedia shows the spoke pattern to be very deep).

just reads like a press release. All the positives are very positive, and the negatives are both very mild and eplained away as solved in later versions. For example they mention minde deflection and the possibility of reducing hydroplanning but do not mention noise or vibration issues at highway speeds.

"... the initial prototype automotive Tweel tires did demonstrate flaws with regard to noise and high speed vibration ..."

The entire automotive industry makes way too much money on tires for them to allow something like this to develop.

Reinventing the wheel http://en.wikipedia.org/wiki/Reinventing_the_wheel

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