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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’

#61

Post by eesmith »

TeMPOraL wrote: post #34

While this particular instance looks a bit unbelievable (where does the stored energy come from?), I wonder if there's more unrealized potential for spring-based energy storage. I'm reminiscent of a sci-fi book someone on HN recommended to me the other day[0], "The Windup Girl". In the post-climate-catastrophe world depicted there, there's scarcity of energy sources; no energy-dense fuels to power modern technologica…

> "use of beasts of burden ... to wind up large springs and power other machinery"

Needn't be just beasts of burden. People used dogs to turn roasting spits - https://gizmodo.com/medieval-kitchens-used-a-specially-bred-... .

IANA genetic engineer, but plants -> alcohol/biodiesel -> power seems likely more efficient than plants/feed -> animals -> mechanical energy storage -> power.

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

#62

Post by zero_deg_kevin »

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…

I always thought the F1 kinetic energy recovery systems (KERS) were a pretty neat mechanical solution. Probably way too heavy for bikes & low-torque humans, though.

https://en.wikipedia.org/wiki/Kinetic_energy_recovery_system

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

#63

Post by throwaway2245 »

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…

> In a test clip a guy pushes down on tire and the lifts the tire and it spins ligthly.

Doesn't this happen with any bike wheel? If I give a wheel a near-imperceptible horizontal nudge just as the wheel lifts off the ground, a bike wheel should be frictionless enough to move at least that much.

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

#65

Post by FerdSlav »

If this really worked and made such a drastic improvement why not get one of the plethora of bike power meters available on the market and show the needed effort to maintain a set speed with this wheel and without?

Also, if this really worked as described it shouldn't matter if it's on the front, back, or both wheels. So why not show that?

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

#66

Post by elliottkember »

RegnisGnaw wrote: post #64

"An Ireland-based entrepreneur is claiming to have invented a power-assisted bicycle wheel that doesn’t use batteries, doesn’t need charging, is not speed restricted and has an infinite range." AKA Perpetual Motion

Well, a spring is a battery. You charge it by compressing or stretching it. I think this battery stores vertical motion - from when you first get on, and maybe if you go over bumps.

But the "infinite range" thing is nonsense.

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

#67

Post by function_seven »

dclowd9901 wrote: post #42
jeremysalwen wrote: post #40

Earlier quoted context omitted.

There's something fundamentally missing from that explanation, because it doesn't explain where the energy is coming from. You can't load a spring without providing energy, and gravity cannot provide energy in a steady state system.

Then how does it assist for gas springs? The reason it _isnt_ hard to push your trunk lid down is because gravity is helping you do so. If you take that gas spring off the trunk, suddenly you need a lot more force to compress it. I don’t understand your explanation: you can’t load a spring without energy, gravity + mass loads a spring, but gravity + mass isn’t energy. It is literally potential energy isn’t it?

So in the trunk lid example, the energy that helps raise the lid was stored in the spring from the last time you shut the lid. The gas spring provides resistance on the closure, and assistance on the opening.

With this wheel, the energy that goes into compressing the 12 o'clock spring must be provided (partially!) from the expanding 6 o'clock spring, plus additional energy from the cyclist to cover the mechanical losses in the system.

I don't see any left over energy that can be used to help with forward propulsion. Maybe on very rough terrain it helps out by trading forward velocity with assistance up a bump, then trading the gravity on the other side of the bump to push forward again. But that's a far cry from the claims being made on the page.

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

#68

Post by [deleted] »

FerdSlav wrote: post #65

If this really worked and made such a drastic improvement why not get one of the plethora of bike power meters available on the market and show the needed effort to maintain a set speed with this wheel and without? Also, if this really worked as described it shouldn't matter if it's on the front, back, or both wheels. So why not show that?

[deleted]

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

#69

Post by Talanes »

RegnisGnaw wrote: post #64

"An Ireland-based entrepreneur is claiming to have invented a power-assisted bicycle wheel that doesn’t use batteries, doesn’t need charging, is not speed restricted and has an infinite range." AKA Perpetual Motion

Ironically, about the only vehicle that actually does meet all those criteria is a standard bicycle.
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