The animation is somewhat misleading. Each of the three loops has a constant length. In the animation it looks like one loop gets longer whilst another gets shorter but that is not the case.
In case people don't know, this was a successful Kickstarter a few years ago for bike wheels. They went to bike shows with a lot of enthusiasm but given the additional weight and cost it was likely a hard sell. Great to see they are still around!
Suspension sits between a wheel and the vehicle so the entire wheel is displaced over a bump which means it’s momentum exaggerates a shock.
Deforming the wheel means far less mass is moved and thus momentum. This is why we use air filled rubber tires in the first place, but they have real size limits. So, this could actually provide a smoother ride.
Probably not worth it for a bike, but someone with a broken bone for example can be extremely sensitive to shocks.
On a bike the total weight also includes the fork and parts of the suspension. Not sure about wheelchairs, but I suspect deforming the center of the wheel still easily cuts unsprung mass in half.
It's very important to reduce unsprung weight, which this does. Vehicle suspension is extremely complicated with a huge number of interrelated variables. It is always possible to make suspension work better, but normally at the price of being more complicated/more expensive. This is a clever idea that isn't that complicated.
How is this different from simply reducing the tire pressure?
Your body weight is constantly pressing down the rotating axis from the center of the wheel so in order to move forward you'll be spending energy on compressing the next section of the wheel equally much? Even if you get some of that energy back once the rear section of the wheel decompresses it's never going to be 100%.
It might have some benefits compared to a loosely inflated tire in terms of more parameters to calibrate and less road friction but this will never come close to a suspension locked in the vertical direction on the frame in terms of efficiency. Maybe this is not an important factor for wheel chairs?
Edit: Actually the softwheel has an efficiency comparison which claims it's more efficient than both rigid frame and fork suspension, even on flat ground http://softwheel.technology/technology/#softwheel-science-wo..., maybe if you bike fast enough the wheel never has time to compress so it's still considered round and center?
Matbe it is just me, but isn't £799.00/£849.00 (ex VAT) a tad bit steep as a price?
Not that the alternative posted of "softwheel" are any better, 2250/2800 $ for a couple wheels?
I have quickly browsed through both sites and they seem to put an accent on lower maintenance costs, but for that kind of money you can buy new (traditional) wheels every other month or so ...
Bonus, an article (seemingly actually published) on the matter, it's a short one, only three pages that is IMHO worth reading, only to have an idea of what can be published:
The loop wheels concept is found which has become a very beneficial to the world which reduces the
wear and tear of bearing that makes novice after completion its specific life which increases the cost and
maintenance of a bicycle. In this case the loop wheels gives a better results and reduces this all the bad impacts
created by the normal cycles and gives a one new morning to the innovation.
The first site that I got from searching for "buy wheelchair wheel" has what seems to be a decent range of off-road wheels. £144 for the cheapest, up to £320
for the end of the "cheap / mid". These loopwheels are on there, and have a similarly priced "fat wheel" to compete with.
2-4x the price doesn't seem too bad tbh; its specialist gear for a non-standard use case
A friend of mine has these on a folding bike. I've ridden it a few times, and it seems fine. He certainly likes them - he considers it a shame that he can't get any more!
In their FAQ they say they're working on MTB wheels, but that the challenge is the (lack of) lateral stiffness in a bigger wheel, which makes sense. The larger the diameter the spring needs to cross, the harder it is to have it only flex in one dimension.
I would imagine weight - especially for road bike tyres.
For comparison, a lightweight Zipp wheelset comes in a just over 1Kg. A mid range lightweight set will be in the 1.4Kg range.
There are other ways to make a road bike handle bumps and road buzz, e.g. specifically constructed carbon seat post, or flexible seat stays.
A good race to watch for these kind of things is the Paris Roubaix, some of the bikes had rubber inserts to the seat stays a few years ago, but now have enough damping just from carbon layup of that section.
How much does it increase friction and would this be feasible on other vehicles as well? Once electric cars are eventually here, their wheels will be the primary noise emitters.
Friction and noise aside, it's better to have the suspension built into the frame rather than the wheels. Added weight in the wheels adds to rotational inertia, which is harder to overcome than linear inertia. A rough rule of thumb is one kilogram in the wheels is worth two in the frame for a car in terms of acceleration.
Tire noise, mainly produced by the vibration of the tire wall, becomes the prime component in the noise production of 'regular' combustion fueled vehicles as well when you go >35km/h. In terms of noise, an electric versus a combustion car doesn't make much of a difference outside very low and in practice almost never driven speeds.
When we are talking noise terrorists with car mods added specifically to pollute the audiosphere, that is different ofc.
Residential streets are mostly limited to 30 km/h here and even the largest inner-city streets have a limit of 50 km/h which is rarely reached due to traffic jams, traffic lights etc.
You mean motorcycles? I cannot understand how any stock motorcycle can be as loud as a completely modded car and be street legal to the detriment of everyone else.
It is fairly easy to make modern engines, even when housed on motorcycles, and most certainly when mounted in cars, relatively quiet.
A lot if not most of the modern car's engine noise is now made deliberately. Special noise chambers are added to amplify and shape the sound, acoustic isolation is foregone in design, and even in some cases engine noises are actually produced by speakers mounted on the vehicle.
You mean in the 'loud pipes save lives" sense? That is just the same as saying "When I go for a drink, I'll first poison everyone in the bar to reduce the chance of someone attacking me"
But that is something you should not get rid of in electric cars anyway. They emit already much less noise than regular cars and are thus harder to hear by pedestrians. You don't really want super silent 1ton metal blobs moving around at 30++km/h as far as I know
I really think I do. The traffic noise in cities makes conversation impossible almost everywhere outside (I'm hard of hearing); meanwhile public places inside that would otherwise be quiet enough get filled with music. Yes, making quiet cars safe is a challenge, but why not try solving it before assuming a bug is a feature?
Yep, a Prius running slowly on battery power is silent enough that people tend to just walk right in front of you since they can't hear it coming...but also makes it easy to sneak up on someone and hit them with the horn for some entertainment value, gotten quite a few friends (and jaywalkers) like that.
I was talking with a blind guy a while back about the beeping crosswalk things and he was saying he had to quit walking to the corner store because the intersection didn't beep and he almost got run over too many times since he had a hard time figuring out which direction he was able to walk by listening to the car noises alone which near silent cars would only exacerbate. Probably be easier to make all the crosswalks beep instead of forcing cars to make unnecessary noise pollution but until that time...
Awareness of what's around you is greatly aided by a bit of noise. Given the early failures of self driving cars and what we know about mechanical reliability of normal ones, I don't think I want to pin my life or the life of my children on some automatic stop that might not work. Better to be able to get out of the way sooner.
Our joint use of the public streets is based on a certain trust that drivers will not try to plow into people. That doesn't mean you have to recklessly abandon all precaution, but it does mean that there are always going to be edge cases that are unmitigated. I think the vehicle based terror attacks have sadly illustrated that point.
Walking the streets in a defensive mode that assumes low speed sneaking up by a driver intent to kill, or being completely oblivious to the surrounding, while at the same time driving a vehicle with defects in its core functions feels like an edge-case. The near ubiquity of people walking or cycling with headphones, or fully being fully engaged with their mobile phones seems to support that.
Cars are dangerous and operated without proper care for sure, but there are very, very few injuries from ultra low speed collisions with cars.
On the other hand there is enormous evidence of serious stress caused by traffic noise having an impact on health.
The whole 'car noise' thing was lobbied by car-makers hoping to cash in on a 'custom ringtones for cars', modeled after the mobile phone market of the 90's. Do you believe that these random noises will avoid more deads and injuries than those created by the resulting stress and 'postal' incidents by those having to involuntarily suffer this?
There are better options. Have slow moving cars emit a low powered radio or radar signal instead. Very compact and extremely low cost detectors and emitters already exist for those. Those that wish get a proximity warning without harming innocents, and as a added bonus this also works for people with reduced hearing, either because the have a hearing problem, or because they are wearing headphones.
The only ones that would suffer a tiny bit are the car makers missing out on selling sounds. Can't say I'm very sympathetic to that crowd as they have amply shown a lack of responsibility and care for people's health and well-being . As usual, the benefits they want to pocket are once more blatantly oblivious to the societal downsides as they have been fully externalized for them.
The bending itself involves internal friction. If it didn't, you'd oscillate forever after hitting a bump.
I'm not an expert on this stuff, but I would be surprised if it were as efficient as a normal wheel when on flat ground. The vibration study page states they will publish numbers on the rolling efficiency of the wheel 'soon'.
Maybe good for wheelchairs where comfort is crucial, but for anything else (bicycle, car) it would waste a lot of energy, not to mention the rigidity issues.
I wonder if the wheel is more suited to wheelchairs because they are pushed at the rim, rather than turned from the hub (as in a bicycle or car). The whole mechanic whereby the hub moves eccentrically relative to the rim when the springs compress seems likely to create all kinds of rolling resistances if the wheel is being turned from the hub - or even if it is being pushed along undriven by a load at the hub. But the unusual rim-driven mode of wheelchairs maybe is the sweetspot for this kind of thing? In particular, it seems that by compressing the springs in particular directions, torques on the wheels will create linear forces on the load - and vice versa - which might be helpful for things like getting a wheelchair up a curb, or over a bump.
As long as the deformation of the loops is largely elastic, it shouldn't waste significant amounts of energy since the energy stored on every 'up' bump should be returned on 'down' bumps.
The side-to-side rigidity is my worry about it, but I imagine that could be arbitrarily increased by widening the loops.
Odd that you have to read quite far down the site's text until they give the context of the type of wheels they're selling (ones for wheelchairs). The pictures in the background do not make it obvious either.
Presumably the site was designed by someone close to the company, who obviously knows the product and didn't get it tested on users who didn't know the product (or they'd have picked this up)
The site didn't load like that when I posted my comment. I had gone back a second time before posting, to be sure. It had a much darker image where it wasn't clear what the item was (you could see the wheel but due to the angle and the dark filter, not what it was part of)
Now I agree there is a video of a wheelchair loading, so context is clear now. Would be curious to know if someone changed it.
Looks interesting but I would worry about how durable it is. It seems like if one of the springs breaks then you are stuck and you probably have to get in contact with them for a replacement that could take a while.
There is a German Opel-manufactured bicycle in the Ulster Transport museum that has short springs mounted all around an inner rim with a metal outer band retaining them.
Apparently due to the shortage of rubber during WW1 which made pneumatic tyres infeasible but I also wonder about oscillations.
But with composite leaf springs, I'm guessing that they could make them less perfectly elastic. That'd damp out oscillations, but also increase rolling friction on bumpy terrain. However, vibration also dissipates energy. My mechanics is inadequate, but they very likely optimized.
1.https://www.loopwheels.com/wp-content/themes/meat/library/im...
2. https://www.loopwheels.com/technical/how-does-it-work/
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