can't quite work out how this works, but looks quite clever....
http://www.huffingtonpost.com/2013/11/09/smart-wheel-flykly_n_4247102.html
CityCyclingEdinburgh Forum » Infrastructure
Smart wheel
(15 posts)-
Posted 10 years ago #
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Seems to be a similar concept to "dynamic" or "regenerative" braking in trains, where resistance generated in the traction motors is used as a form of braking, either being dispelled as heat from a bank of resistors (which is why the roofs of Virgin Voyager trains had a habit of catching fire when fed with Autumn leaf fall) or fed back into the overhead lines. Only in this case I assume it's being stored in a battery
Posted 10 years ago # -
"As far as 30 miles on one charge".
They're either lying or that's one unbelievably heavy wheel.
Posted 10 years ago # -
I think it's crucial that it's pedal assist - i.e. it does nothing unless you are pedalling yourself. That might be stating the obvious, but it took me a while to work out how it would work....
Posted 10 years ago # -
The article crashes my browser but does it mention how powerful it is? It may be a fairly weak motor but even 100w would be a help, your average commuter probably never generates more than that on the flat. 100w would only need a fairly modest battery, especially if its regenerative, 30 miles is only 2 hours use at a modest pace.
Posted 10 years ago # -
sorry about posting a link which crashed browsers - it is irritatingly full of flashy things and adverts. I can't find out any power info - here's a youtube video of the thing...
http://www.naden.de/blog/bbvideo-bbpress-video-plugin -->
[+] Embed the video | smart wheel video" target="_blank">Video Download Get the Flash Video Posted 10 years ago # -
Shonky browser more than anything. Do they mention how heavy it is any where? I am curious now.
Posted 10 years ago # -
Their website is rather pants. It wants your money (Kickstarter) with precious little detail about how it works and how it performs. I'll keep my wallet shut I think. I've got better things to spend $550 US on!
Posted 10 years ago # -
http://www.kickstarter.com/projects/flykly/flykly-smart-wheel
It apparently weighs 4kg which whilst pretty heavy isn't that bad. LI-ON gives ~250wh per kg, say 1.5 kg for the motor and wheel leaves 2.5kg for battery which is 600 wh. Take away something for efficiency loses and you'll get a useable 400wh which gives about 200w for two hours, probably more like a 250w motor given its up to 2 hours.
More iritatingly it uses a dynamo to run the front light and (required) iPhone charger so wasting energy to propel the bike then wasting more in the dynamo all so they can avoid running a wire from the charger to the battery...
Posted 10 years ago # -
there's an app and a robust housing - what more detail do you need? I didn't see the price - I just remembered I like using my legs.
Posted 10 years ago # -
@steveo - thanks for explaining that - not sure I understand the last bit though...
"probably more like a 250w motor given its up to 2 hours"
Agree about the dynamo - seems pretty ill-conceived, but I think if it works as I guess it does then the charging part only works on deceleration of the crank with respect to the motor, so pedalling itself doesn't charge it, so once it's dead you'd have nothing to power the front light (unless you're going downhill).
Posted 10 years ago # -
up to is usually the get out of jail free card if it was a 200w then you'd probably get upto 2.5h hours.
True, though the light would draw so little power compared to the motor that a slightly clever charge controler could cut the motor when the battery got to, say, 10% and leave days of charge left to the run the lights or iPhone.
Posted 10 years ago # -
@steveo - thanks for that. I understand now. Brain a bit feeble.
Posted 10 years ago # -
This looks every like the Copenhagen Wheel developed at MIT in 2009...
Posted 10 years ago # -
so it does! (sorry wasn't aware of that)
Posted 10 years ago #
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