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Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

cyclingweekly.com

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Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#51

Post by dclowd9901 »

KaiserPro wrote: post #44
fergie wrote: post #7

Would love to hear the opinions of some actual mechanical engineers. Can these springs really passively get you +30% efficiency? What about weight? Cyclists are obsessive about reducing rotating mass, and these wheels seem to be seriously chunky. Is this actually a thing that could work?

The springs are compressed as the wheel rolls forward. this means added rolling resistance Those springs are then decompressed either into another spring inside the drum, or back into the wheel again. if its option 1 where the springs we can see are decompressed into a central energy store, it might have some application for allow easy starting (ie you press a button and the wheel lets out all its stored energy and s…

Let’s say you have two boards end to end, each on fulcrums, angled up like an A. Leading to the apex of the two boards, you have a platform at about the height of the apex.

Now let’s say you to take a step forward off that platform onto the apex of those two boards at the same time, pushing them down and lifting their ends. Do you have to expend any additional _forward momentum_ energy to take that step?

Now let’s say there was a big spring between the opposite ends of those two boards, and that spring just happened to compress at a weight a bit lower than force generated by you stepping onto the apex.

Now, imagine stepping off the apex. As you do, you feel the apex rise and push your leg off.

Now apply that mechanic around an axle, and use mechanics to ensure only the springs nearing the top of the axle (as it rotates) compress when downward force is applied to the axle itself. That’s as good as I can describe how I understand it, and I can’t see how it violates any physical laws. It’s just a clever use of springs.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#53

Post by franciscop »

wiredfool wrote: post #45
franciscop wrote: post #26

This article has all the makings of a perpetual motion machine. Those are normally found by using either "springs", "magnets" or a combination of both. There is theoretically a way to use the roughness of the terrain (so the bike going up and down as it rides) to store that energy and then use that for propulsion. When finding a rough spot, the bike trades forward momentum for a vertical impulse, so it might be possi…

There is some research into how much energy is lost to suspension style losses, and it's on the order of 100W (was 300) when riding at 20mph/30kph over rumble strips. ( https://www.renehersecycles.com/myth-17-bigger-wheels-roll-f... ). This can be changed pretty dramatically with good tires and proper inflation. On more reasonable road surfaces, it's less than 1/10th of that number. (but good tires make ooooh so much…

Thanks for linking the article! It seems to say that 300W is the energy needed on the rough terrain, not the energy consumed by the bumps: "We measured the power required to pedal the bike at 32.2 km/h (20 mph) using an SRM crank."

Then it goes on to measure the energy required on the smooth pavement and it's around 230W. So around 70W of INPUT energy is needed because of the strips.

Now if speed is constant, it stands that a part of these 70W are converted to vertical motion (the rest lost to heat in many forms). This is where I don't dare to understand thermodynamics enough to even make an (un)educated guess of how little of those 70W are converted to vertical motion.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#55

Post by me_me_me »

franciscop wrote: post #26

This article has all the makings of a perpetual motion machine. Those are normally found by using either "springs", "magnets" or a combination of both. There is theoretically a way to use the roughness of the terrain (so the bike going up and down as it rides) to store that energy and then use that for propulsion. When finding a rough spot, the bike trades forward momentum for a vertical impulse, so it might be possi…

I had quick look around and it doesn't seem to be an actuall scam.

They have them out in the field selling small batches and there is no telltale 1 million $ kickstarter promising rocket bike powered by solar and wind pressure.

This device seems to be capturing a kinetic energy and storing it in the springs that release it to assist/smooth-out peddling? In a test clip a guy pushes down on tire and the lifts the tire and it spins ligthly. Akin to a gently push you would give to spin a wheel when fixing it and checking if its aligned (actually its less force then that).

I wonder how much of assist energy it really generates and if it makes any difference.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#56

Post by ACAVJW4H »

Evidlo wrote: post #19

Initially I thought this was some kind of mechanical regenerative braking. I wonder if that's been attempted before. Applying the brakes would wind a spring and bring the bike to a stop. Then applying force to the pedals or manually pulling a lever would release the spring for an assisted start. Edit: Here's some mechanical regenerative braking projects: https://m.youtube.com/watch?v=yK7fyugbe6o https://m.youtube.com…

Tom stanton a great youtuber builds and tests prototypes like these. Here he tried electrical regen

https://www.youtube.com/watch?v=-suxSqrP_X4

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#57

Post by franciscop »

me_me_me wrote: post #55
franciscop wrote: post #26

This article has all the makings of a perpetual motion machine. Those are normally found by using either "springs", "magnets" or a combination of both. There is theoretically a way to use the roughness of the terrain (so the bike going up and down as it rides) to store that energy and then use that for propulsion. When finding a rough spot, the bike trades forward momentum for a vertical impulse, so it might be possi…

I had quick look around and it doesn't seem to be an actuall scam. They have them out in the field selling small batches and there is no telltale 1 million $ kickstarter promising rocket bike powered by solar and wind pressure. This device seems to be capturing a kinetic energy and storing it in the springs that release it to assist/smooth-out peddling? In a test clip a guy pushes down on tire and the lifts the tire…

That's possible; there's energy when you sit down, but not just for "being sitted down", only when sitting down or standing up. Having a look at the "how it works" website and how they claim it's energy just because of your weight I double down on a scam:

https://www.superwheelsystem.com/how-super-wheel-works/

If it was as claimed, you would be able to put this in a circular road, add a lot of weight and then have a motor provide N watts of power and get out M > N watts of power.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#58

Post by wiredfool »

franciscop wrote: post #53
wiredfool wrote: post #45

Earlier quoted context omitted.

There is some research into how much energy is lost to suspension style losses, and it's on the order of 100W (was 300) when riding at 20mph/30kph over rumble strips. ( https://www.renehersecycles.com/myth-17-bigger-wheels-roll-f... ). This can be changed pretty dramatically with good tires and proper inflation. On more reasonable road surfaces, it's less than 1/10th of that number. (but good tires make ooooh so much…

Thanks for linking the article! It seems to say that 300W is the energy needed on the rough terrain, not the energy consumed by the bumps: "We measured the power required to pedal the bike at 32.2 km/h (20 mph) using an SRM crank." Then it goes on to measure the energy required on the smooth pavement and it's around 230W. So around 70W of INPUT energy is needed because of the strips. Now if speed is constant, it stan…

Yes, I edited that when I reread the article.

The conclusion drawn from the article is that the 70+W is vibration of the bike that is damped (lost) in the rider's body. Adding suspension by running supple tires at lower pressure reduces the energy required to go over the rumble strips (https://www.renehersecycles.com/myth-16-higher-tire-pressure...). That one compares 26mm tires at 75 vs 95 psi, but there's a page somewhere that I think shows wider (think 42mm+ tires) at more like 25psi.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#59

Post by me_me_me »

franciscop wrote: post #57
me_me_me wrote: post #55

Earlier quoted context omitted.

I had quick look around and it doesn't seem to be an actuall scam. They have them out in the field selling small batches and there is no telltale 1 million $ kickstarter promising rocket bike powered by solar and wind pressure. This device seems to be capturing a kinetic energy and storing it in the springs that release it to assist/smooth-out peddling? In a test clip a guy pushes down on tire and the lifts the tire…

That's possible; there's energy when you sit down, but not just for "being sitted down", only when sitting down or standing up. Having a look at the "how it works" website and how they claim it's energy just because of your weight I double down on a scam: https://www.superwheelsystem.com/how-super-wheel-works/ If it was as claimed, you would be able to put this in a circular road, add a lot of weight and then have a…

I think that as you pedal you shift your weight, also wobble a bit, and any uneven road surfaces can be harvested theoretically by this.

This doesn't create free energy it just captures inefficiencies created by transfer of energy from your muscles to the wheel.

But there is no free cake. This can't work by just sitting still at it :)

Also 30% improvement sounds like a outright lie or marketing PR talk.

Anyhow even if real i dont care about +300$ wheels.

Re: Spring-powered wheel claims to be ‘E-bike alternative at lower cost’

#60

Post by jl2718 »

Deceptive marketing, but it’s actually a brilliant suspension. Just looking casually, it appears that the ratchet mechanism is used to convert an oscillatory energy into a mechanical energy. Most suspensions just turn it into heat.

It may make more sense by analogy to an electronic rectifier. The ratchet is like a diode and the spring is like the capacitor.

The energy still comes from the legs, but it helps capture losses. I can think of a lot of ways to improve it, and make it simpler, but it’s the first time I’ve seen something like this actually built.

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