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Clever idea. I especially like the ability to easily add electric assist to any bike (and in the video Britt mentions even fitting it to a unicycle!!), since these days almost all electric assist conversions involves replacing a wheel. I’m a little dubious about jamming a 200W motor and its battery into a pedal, though.
I see zero reason to think this is anything other than a crank (ha ha!) idea. Since your feet/legs will have to resist the torque from the pedals in order for it to be translated to the bike, it doesn’t seem you’re being assisted at all. Equal and opposite forces, right? A person just biking in a video isn’t at all convincing.
The only way I could see it working is if you maybe adopted some kind of rigid standing position. That way, gravity would provide the opposite force. But that doesn’t seem like it’d work too well with the need to transfer weight to the front pedal to go forward at the same time. So *maybe* it might offer some help hammering up a tough climb, but I have my doubts that it’ll be worth the additional weight you’d be pushing around all the other times.
All you’d need to do is clip in off-centre (in the forward plane)..the sole of the shoe/foot would act as leverage (fixed cantilever) Not efficient for pure pedaling but would make the power assist very effective as it would resist the rotation of the ankle mecanically…A brilliant idea…when minaturized will be be superb…another job for Graphene!
The same way that a cordless screwdriver dosent make putting in a screw easier, as you have to resist the back force..?
The hassle with screws is not the “back force”, it’s that our wrists don’t rotate 360 degrees. And, yes, you are expending energy to fight the torque of the motor even then. The advantage you can gain, just as I noted with the bike, is if you lock up while using it. People don’t twist their electric screw drivers, and you shouldn’t expect to pedal normally with these things. The presentation is misleading, at best.
Yes but the screwdriver is working on the one axis, if I were to rotate the cordless screwdriver in a larger axis it would make no difference whether it were switched on or not, the power is still coming from my arm. Similarly the legs are still required to rotate the crank. Could you please give details how this system works?
With 100 Watt on one pedal you get about 15Nm torque on the pedal.
This means about 30 Kg want turn the pedal.
For getting 100 Watt you need about 200 Watt from the battery.
A battery in the shown size has max about 10 Wh.
After 3 minutes the battery is discharged.
Stephen, can I buy a set of pedals. Contact details?
Actually, it can “work”, but only at relatively low powers (low enough the back torque doesn’t knock your feet off the pedals or hurt your legs.)
Having the pedals not unscrew themselves from the crank may be an issue.
Some kind of torque arm assembly that hangs onto the crank may be required.
The practical issue is can it deliver enough power to matter, while still being workable for human feet/legs, and with enough battery life to be worth the bother.
Is it really that much hassle to just pedal harder on a regular bike?
If this wins £50k I’ll be grumpy all year.
“Is it really that much hassle to just pedal harder on a regular bike?”
I guess it depends on the rider. It is certainly not an issue for me or for you, but what about an older person with a basket full of groceries. I view e-bikes as an alternative to short car trips for some people, not replacements for standard bicycles. If e-bikes (or electric accessories) have potential to introduce new people to the idea of cycling for transportation, then I am all for them.
Though I doubt the amount of older people who have trouble pedalling their groceries home is a sufficient market on which to build a business.
Let’s watch this space!
I totally agree: this looks like yet another costly gadget… like the electric corkscrew. It may lightly assist pedaling, but what is the point? For more efficiency you’d need the pedals to be as long as your foot…
The cost of the item, the risk of damaging it (pedals are one of the most exposed parts of a bicycle), the unecofriendly production of batteries, the extra weight, in my opinion too many things sadly make it a worthless invention.
I had the bearings go out on one of my platform pedals a few months ago. Trying to keep my foot on was next to impossible. I could imagine the experience wtih powered pedals to be the same going the other way without clips or cleats…kind of anti-ebike.
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ITM » Archivo » Fast Forward: pedales eléctricos para que tu bici te conduzca a ti
This is a great idea. I imagine the inventor started with a small portable electric drill and made modifications from there. This beats the motor-driven roller on tire approach because the benefits of the bicycle’s gearing can be had. Placing the pedal pivot forward might alleviate most back-kick worries while starting new ones. Reducing force on unpushed parts of the crank rotation could be done with irregularly spaced contacts from an on-frame battery–or it could be programmed into the motor as done here apparently.
Flat wire tape should be used to wire pedelects and electric bicycles, since it can disappear under the paint and strengthens tubes. A more sophisticated approach might involve conductive wire mesh that could be baked into carbon fiber, too, for electrical functions on the handle bar, the seat, and the frame. I’m waiting for ‘drive by wire’ to come to bicycles & LEV’s, too. A guy at Stanford may have done this only to be ragged on by everybody.
Not shure how this would work, wouldn’t the pedal just spin around and not propel the bike forward?
Anyway, if it works, this is what I’ve been looking for. I’ve tried to retrofit a tandem tricycle with assisting motors but has not been able to due to the internal gear hub in the back wheel and hub breaks in the front wheels which leaves no room for a motor.
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To simulate what these pedals will actually do, imagine placing a pedal wrench on each of the spindles of your bike pedals. On the right pedal spindle, you apply a clockwise torque; on the left pedal spindle, you apply a counterclockwise torque. The net effect is that these torques on the spindles will tighten the spindles in the crank arms’ threads until they cannot tighten anymore, then start to translate torque into rotating the crank arms around the bottom bracket, thereby moving the bike forward.
The concept is correct in terms of applying the correct direction of forces to propel the bike forward.
However, there are at least 2 issues:
1st, normally a rider applies force directly on the crank arm at the spindle point tangent (or perpendicular) to the crank arm. The bearings within the pedal limit the rotational torque applied to the spindle/crank arm threads. This method here intends to place very high torque on the threads, which they are not designed to withstand. The likely result is that if there is actually enough torque generated by these pedal motors to effectively propel the bike, the crank arm threads will likely strip quickly over time.
2nd, the small dimensions of practically-sized pedals (so they do not hit the pavement or extend sideways and hit obstacles) and existing technology of motors and batteries (for at least 5 years out) will likely not provide enough energy for sustained torque in the intended electric assist application.
If we actually see this product successful in the market, I’d be proven wrong.
There wont be a thread looking at the pedal…it looks like a keyed interface, which would solve that problem…
Minaturisation will follow…it’s clearly been ‘homemade’ to a very high standard but once developers get into it there will be shrinkage…
Unique ebike drive trains | hatszel.hu / ebikeee.com
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