Super wheel converts rider's weight into forward movement!

[mattvarley]

Been contemplating an electric bike for a while but can't bring myself to move to the dark side. Good halfway house if it works

 

[MichaelW2]

Could you put a piezo electric device onto each spoke to convert tension/compression <ducks> into a spark?

 

[gcogger]

But your body is constantly being pulled into the ground, that's what puts tension on the top spoke when you sit on your saddle. As that spoke rotates with the wheel some of that tension is released until it's at minimum tension at the bottom, I assume it's that effect they're trying to harness, turning the 'free energy' of gravity into forward motion. Like if you sit on a spring it will compress, and if you tilt the spring forward it will eventually push you forwards slightly more than if you had tilted a static platform.

Whether that effect exists in significant enough quantities to make this wheel worthwhile, probably not, very unlikely to be 30%, and the look of their efficiency report didn't fill me with confidence.

You can only obtain energy from gravity, or the weight of something, if it loses height. No need to complicate things further.

 

[Once a Wheeler]

Click here to see this and other super wheels in action:

Doubtless all powered by cold fusion. This must be why my legs get hot riding up hill on a winter's day. Will the SuperWheel be taking its place amongst them? Note the name of the web page where they appear.

 

[Twilkes]

You can only obtain energy from gravity, or the weight of something, if it loses height. No need to complicate things further.

But you can store it, and release it in a direction where it's not fighting against the same force of gravity? It's not a static situation, the effect of the rider's mass along any radius of the wheel changes as it turns and the spokes at the bottom are unloaded (that's not controversial, right?) and then become loaded again as they turn, you can see the same effect on the contact patch on the tyre, the rider's static mass compresses a different part of the tyre as the wheel turns, but the energy of it reforming is lost.

If their springs are being compressed by body weight (i.e. no 'power' is being put into them by the rider) and then being released further round the rotation helping the wheel to turn, then they're trying to store and release energy.

I'll try to decipher the report on LinkedIn to see what they're on about.

 

[Profpointy]

You can only obtain energy from gravity, or the weight of something, if it loses height. No need to complicate things further.

Huge amounts of energy can be produced by this. The black holes at the centres of galaxies can power huge quasars radiating far more energy than the stars purely by heating up gas falling in.

However with the bike thing, once the heavy rider has been lowered to the ground then that's all the energy used. And how does he ride the bike once he's flat on the floor

 

[byegad]

See also chainless drive, arm and leg powered bikes and perpetual motion machines!

Best laugh I've had for ages!

 

[gcogger]

But you can store it, and release it in a direction where it's not fighting against the same force of gravity? It's not a static situation, the effect of the rider's mass along any radius of the wheel changes as it turns and the spokes at the bottom are unloaded (that's not controversial, right?) and then become loaded again as they turn, you can see the same effect on the contact patch on the tyre, the rider's static mass compresses a different part of the tyre as the wheel turns, but the energy of it reforming is lost.

If their springs are being compressed by body weight (i.e. no 'power' is being put into them by the rider) and then being released further round the rotation helping the wheel to turn, then they're trying to store and release energy.

I'll try to decipher the report on LinkedIn to see what they're on about.

That's what I mean about "complicate things further"
Unless the rider is getting lower and lower during the ride, you haven't obtained any energy from their weight. Worrying about how spoke tensions change, or springs compress/un-compress, is just doing an over-complex (and therefore harder to get right) analysis of a simple situation.
The only way this could improve efficiency is if there was energy being lost somewhere, e.g. due to the rider's weight going up and down. The only scenario I can think of where that happens is if you're riding out of the saddle but, in that case, the energy is already being very efficiently used by the bike's drive train!
It's possible (although I doubt it) that there are other inefficiencies in the system addressed by this device, but that's not getting energy from the weight of the rider.

 

[Twilkes]

Because it's a slow day I found the patent document, and it's essentially an inner hub, loosely connected to a larger outer hub and some kind of arm attachments which are each attached to a spoke with a spring. With no load the two hubs are concentric and all tensions are equal. When a rider sits on the bike, the outer hub is pushed down relative to the inner hub and the springs at 12 and 6 o'clock are compressed/stretched by around 4mm, while the springs at 3 and 9 o'clock remain the same, with the springs between under various stages of compression/stretch.

As the rider pedals, the idea is that the 12 and 6 o'clock springs rotate and rebound back to their normal state at 3 and 9 o'clock, the energy released being turned into rotational force. They would then compress/stretch again under the rider's weight until they got to 12 and 6 o'clock. Doesn't say anything about forces brought about by pedalling or braking though.

So comparisons to perpetual motion machines are unfair because they're not saying that's what it is, it's assistance when the wheel is rotating. One of the tests they reckoned increased the range of an e-bike from 100km to 169km but it was an n=1 with no controlled conditions, whereas I'd have thought, if it worked and the effect was significant, it would be easy to show it under lab conditions.

I still wouldn't buy one unless Wiggle sold it though, the guy invented something called the 'Easy Pedal' about ten years ago and coincidentally also claimed it increased efficiency by 30%!

The 'how it works' starts around page 6, row 37: Patent specification

edit - fark me, it weighs 6kg!

 

[presta]

I know the 'owt for nowt' thing, but if the wheel uses the energy of body mass pushing down onto something static (i.e. that energy would otherwise go into tensioning a spoke), could that energy not be released as the wheel turns? That seems to be what the rotational springs are doing. It's not like you have to compress the springs with your muscles, your body mass is doing that for free.

So it seems they're trying to convert the downward force of your body into rotational force at the wheel, I can't find a decent explanation of how it's supposed to work though.

When you sit on the bike it'll store a small amount of energy in compressing and tensioning some springs, then as the wheel rotates, most* of this energy will be released.........and immediately consumed in compressing the next set of springs in the wheel. The only way the riders weight releases any useful energy is if it ends up at a lower height than it was at the start, which is what happens if you go down a hill, but you don't need any special wheels for that.

*A small amount gets dissipated as heat, so the net effect of that wheel is to absorb energy not produce it.

 

[Twilkes]

When you sit on the bike it'll store a small amount of energy in compressing and tensioning some springs, then as the wheel rotates, most* of this energy will be released.........and immediately consumed in compressing the next set of springs in the wheel. The only way the riders weight releases any useful energy is if it ends up at a lower height than it was at the start, which is what happens if you go down a hill, but you don't need any special wheels for that.

*A small amount gets dissipated as heat, so the net effect of that wheel is to absorb energy not produce it.

How is the energy released from one spring used to compress the next spring? Pushing the pedals will move the next spring under the rider's weight and that's what will compress it, the previous spring doesn't know anything about it.

I'm not arguing that it would add a significant amount of energy, just that I can see the concept and it doesn't seem to go against the laws of physics as some people were suggesting.

 

[Profpointy]

How is the energy released from one spring used to compress the next spring? Pushing the pedals will move the next spring under the rider's weight and that's what will compress it, the previous spring doesn't know anything about it.

I'm not arguing that it would add a significant amount of energy, just that I can see the concept and it doesn't seem to go against the laws of physics as some people were suggesting.

You do work compressing the spring, then a proportion of that work is returned when the spring is uncompressed losing a %. If you hadn't compressed the spring in the first place you would be more efficient. If it increased the efficiency in some way it would contradict the laws of physics. And "ye cannae break the laws of physics" as a certain "Scotsman" once said. In particular it breaks the 1st law of thermodynamics, "you get owt for nowt", arguably the most fundamental of all physical laws.

Look at it another way, if the pedals connected to a clockwork spring as well as driving the wheels, that wouldn't allow you to get free energy when you released the spring as you'd simply be getting back (some of) the work you'd put in winding the spring up

 

[gcogger]

How is the energy released from one spring used to compress the next spring? Pushing the pedals will move the next spring under the rider's weight and that's what will compress it, the previous spring doesn't know anything about it.

I'm not arguing that it would add a significant amount of energy, just that I can see the concept and it doesn't seem to go against the laws of physics as some people were suggesting.

If it doesn't go against the laws of physics, could you tell me where the additional energy comes from? As explained above, there is none coming from the rider's weight/gravity.

 

[Twilkes]

You do work compressing the spring, then a proportion of that work is returned when the spring is uncompressed losing a %. If you hadn't compressed the spring in the first place you would be more efficient. If it increased the efficiency in some way it would contradict the laws of physics. And "ye cannae break the laws of physics" as a certain "Scotsman" once said. In particular it breaks the 1st law of thermodynamics, "you get owt for nowt", arguably the most fundamental of all physical laws.

Look at it another way, if the pedals connected to a clockwork spring as well as driving the wheels, that wouldn't allow you to get free energy when you released the spring as you'd simply be getting back (some of) the work you'd put in winding the spring up

Okay, the rider's mass doesn't do any 'work' while it compresses/stretches the spring, but if the loose hub and spring compression/stretch actually uses up energy from the pedal rotation which otherwise would go directly into rotating a traditional wheel, then yes I could see that. It's claimed it also works while freewheeling though, as the rotation of the wheel is the only thing needed for it to operate.

If that is the case I'm surprised the guy's got this far though, he seems confident that it worked when he tested it!

 

[matticus]

4 pages?!? Blimey ...

I should bookmark this - if anyone on this thread posts again about the science of bike riding, I'll refer back to see what they said here ...