Hills too hard? You need powered pedals!

Help inventor Stephen Britt secure £50k funding...

by Dave Atkinson   June 22, 2010  

Britt Pedals CAD drawing

What's good about electric bikes? They broaden the appeal of cycling and make the bike a viable alternative for more people. And the downside? Well, they tend to be heavy and expensive. Step forward inventor and entrepreneur Stephen Britt, who's in the running to win a £50,000 business development grant. His product? Powered pedals.

Yup, we're not making this up and furthermore it sounds like an excellent idea. The fact is that most people - even those not fit enough to ride up hills - don't need a fully-fledged electric bike that'll do 30 miles under its own steam and weighs 25 kilos. For a start they're likely to be popping to the shops or commuting a short way to work, and secondly they only really need the help on a few bits of the ride where they've got a hill to climb.

Enter the powered pedals. They slot into a charger to get powered up, a bit like a cordless drill, and each pedal has a motor, gearbox and Lithium Polymer battery built in. As you pedal sensors detect how much effort you're putting in and give you a helping hand. If you don't need any assistance you just flip the pedal over and use the other side.

The pedals are at the prototype stage right now but Stephen's aim is to develop them to the point where they'll have a range of 10 miles -fine for the occasional cyclist - and provide up to 200W of assistance, about the same as a standard electric bike. Most importantly though they'll be retro-fittable to pretty much any bike and won't significantly increase its weight. They'll also be all-but-invisible, which should take some of the stigma out of electric assistance. Plus it'll be another opportunity for Pro teams to [snip! - road.cc ed]

We reckon it's a grand idea and worth the fifty grand of investment capital that Barclays are putting up in their Take One Small Step competition. To vote for the peds, point your browser at https://www.takeonesmallstep.co.uk/Entry/View/2462 and make your mark. The outcome of the compo is solely decided on the public vote, so tell as many of your friends as you can! The closing date is 5 July.

24 user comments

Oldest firstNewest firstBest rated

Is this a summer solstice fool or something? You don't power a bike along by rotating the pedals. The only way this could work would be if they were filled with mercury, with a pipe running down the cranks and through the bottom bracket, and a pump to transfer the weight from one pedal each time it reaches the low point in its circle, quickly enough to add weight to the opposite pedal in time for gravity to help pull it down! That or some other Heath Robinson contraption.

posted by handlebarcam [529 posts]
22nd June 2010 - 12:45

2 Likes

you *don't* power a bike by rotating the pedals but that doesn't mean you *can't*. apply torque to the pedal spindle and it'll act against your foot, the upshot being that the cranks turn round.

Nerd Nerd

sounded like i knew what i was talking about then for a minute.

Dave Atkinson's picture

posted by Dave Atkinson [7444 posts]
22nd June 2010 - 13:02

2 Likes

Or sprain every ligament in the rider's feet.

posted by handlebarcam [529 posts]
22nd June 2010 - 13:57

2 Likes

tell you what, vote for him to get his £50k and then we can judge for ourselves Smile

Dave Atkinson's picture

posted by Dave Atkinson [7444 posts]
22nd June 2010 - 15:04

1 Like

Might want to check the Swiss patents office first Wink

Simon_MacMichael's picture

posted by Simon_MacMichael [8288 posts]
22nd June 2010 - 16:17

2 Likes

As an engineer, I can't see how this will work. The force applied by a cyclist is downwards, not rotational. You can apply torque to the pedal spindle, but the torque coming from your feet will have to be nearly equal, so how would it be able to deliver 200 Watts? Also, 200 Watt from such a small battery?
In his pitch he doesn't explain how it works either. If I were to invest money I would like to know how this would work first!
I hope there will be some explanation somewhere, cause if it works it is brilliant!

As there already are dynamos in hubs for headlamps, wouldn't it be better to change this round so you'd just have to change a front wheel? Or even the electric regeneration system as been used in Formula one? Charge the battery when braking or going down hill.

Hmmm, maybe I need to pitch for one of these ideas Nerd Smile

posted by JJ the Flying D... [65 posts]
22nd June 2010 - 16:24

1 Like

Seems like a crap idea to me. The first question is how can you get enough energy storage in there? With current battery technology, I don't believe it's possible. No I haven't done the maths, but I suspect this is the killer. That is aside from the mechanical concerns.

Decades ago , there was a different but still crap idea about bent crank arms.

The scam idea was that you could magically increase the leverage [for free] by having bent cranks. All it achieved was increased mass, plus profits, if they sold enough units. I never saw them in the 'flesh', but it was in the pre internet days, so there wasn't a means of easy information.

I even saw them on the front of a magazine. Apparently they sold, but presumably not well.

http://en.wikipedia.org/wiki/Crankset#Bent_crankarms

posted by Recumbenteer [149 posts]
23rd June 2010 - 7:51

1 Like

I'm sure bent crank arms will be back. Ovoid chainrings are, and remember how we were all laughing at them a few years ago? Smile

Dave Atkinson's picture

posted by Dave Atkinson [7444 posts]
23rd June 2010 - 8:31

2 Likes

Lift a foot off a powered pedal and it will spin like a anemometer. (Sorry for the lame simile; I was trying to think of something really spinny.)

two wheels good; four wheels bad

posted by cat1commuter [1360 posts]
23rd June 2010 - 9:35

1 Like

I believe similiar technology has already been applied to provide power-assistance to pedestrians. The Racewalking community has been rocked by allegations of mechanical doping.

posted by handlebarcam [529 posts]
23rd June 2010 - 10:14

1 Like

Quote:
spin like a anemometer

like a gyroscope in a tumble dryer on a waltzer? Big Grin

Dave Atkinson's picture

posted by Dave Atkinson [7444 posts]
23rd June 2010 - 10:52

2 Likes

dave_atkinson wrote:
Quote:
spin like a anemometer

like a gyroscope in a tumble dryer on a waltzer? Big Grin

Like a whirling Dervish!

Chris's picture

posted by Chris [109 posts]
23rd June 2010 - 12:26

1 Like

Surely any energy that the pedal exerts will need to be matched by equal input from the rider? so for every watt it puts out to the crank, the rider would have to exert the same wattage to prevent the pedal spinning? Seems like a zero sum game to me.

mr-andrew's picture

posted by mr-andrew [299 posts]
23rd June 2010 - 12:50

2 Likes

Strangely enough, all you "engineers" might be wrong. I think that it might almost work. Using just the weight of your legs, the force of gravity holds the pedal down and prevents it from rotating. The reaction from the motor must put a torque onto the crank which will turn it.

Where it does fail is that any battery small enough to fit on a pedal will not have enough power or range to do anything useful.

If it were possible to generate enough power then unless you put effort into putting pressure onto the pedals they are likely to throw your feet off. So you end up using your own power anyway.

Overall, I rate this idea a "fail".

posted by peterkvt80 [4 posts]
23rd June 2010 - 13:18

2 Likes

Trying to be positive about this:

If your foot resists the spinning pedal, then the rotational torque will act like a planet gear and cause a rotation in the bottom bracket. I think...

Not clear how you would carry that energy in a pedal sized unit though. I think the additional rotating mass in the pedal would negate the energy saving from having an electric bike.

If you popped the motor down the seat tube then that might work! Thinking

Bring me sunshine, and dry roads

MalcolmBinns's picture

posted by MalcolmBinns [107 posts]
23rd June 2010 - 13:30

1 Like

The pedal axel makes one revolution for each turn of the crank. The motor drives this. The pedal body uses the foot as a platform to drive against. The foot also rotates the crank with the pedal. RPM and force sensors will measure the cyclists input and feed into a micro controller to work out how much power and torque to give the motor. The motor wont kick in till above say 20rpm. So if you cadence drops below this, no pedal power. If you slow or take you foot off, no pedal spin

When you use a cordless screwdriver, it is easier to put a screw in, though you still have to resist the back force. This is exactly the same, but your foot can resist a large back force. And will turn the pedal at the same time. If you apply a pressure and the pedals match your force, then you can double your output, or put in half the effort.

Look at li-po batteries and BLDC motors from model shops, this is available technology.

The prototype shows the concept well. It needs full development for commercialisation, hence the competition. A patent has been filed.

The product has the backing of, CommercialSE, SEEDA, University of Brighton, I have a business mentor and the support of a member of the I Mech Eng.

Some competitions:-

http://www.commercialise.org.uk/newsandevents/index.asp?id=97

http://www.eastsussexhub.co.uk/news/hub/Jul/The-Hub-finds-new-innovation...

All the best,
Stephen Britt.

posted by stephenbritt [1 posts]
23rd June 2010 - 13:42

2 Likes

Further information can be found in UK patent application GB2466318A (co-incidentally (?) published today!). I have not yet had a chance to read this properly, but at first sight it looks as if drafted by a competent professional (as well as being an electric bike enthusiast, I am a UK patent attorney - although I have no connection with this invention)

posted by SteveU [6 posts]
23rd June 2010 - 20:02

1 Like

Sadly, a patent application doesn't necessarily mean something isn't a crackpot idea. For every genuine invention there are dozens of half-cocked attempts to get funding or put a stake in the ground in the hopes of being able to sue someone for infringement at a later date. Whether genuinely intended or not, you cannot impart any turning force on a crank by spinning something attached to the end of it. Best you could do is somehow sense dead spots in the rider's pedaling action and rotate the pedal a bit stimulate more power output from their legs. It might feel something was being added, especially if accompanied by the sort of electric motor whine you get with a Gruber Assist. Sorry, but in the words of Duncan Bannatyne, when he has finished the physical act of love, "I'm out."

posted by handlebarcam [529 posts]
24th June 2010 - 8:10

1 Like

With a bit of luck and a fair wind, intrepid road.cc South Coast correspondent Jo Burt will be having a go on said pedals this very day. If he manages to get to the demo in time. So stay tuned!

Dave Atkinson's picture

posted by Dave Atkinson [7444 posts]
24th June 2010 - 8:41

2 Likes

This is utter, utter nonsense. A motor powering your pedals around their axles cannot offer any power assistance. Surely there are more sound ideas out there worthy of £50K!! Come on Stephen, think about it!!!

posted by eddieallen72 [3 posts]
24th June 2010 - 10:55

2 Likes

A lot of people on here don't seem to be grasping that he's actually built the pedals. presumably if they didn't work at all he wouldn't be pursuing it.

cactuscat's picture

posted by cactuscat [303 posts]
24th June 2010 - 11:25

2 Likes

Well Iam going to take this as a fantastic idea, and ignore all the would be engineers trying to sound intelligent, if it was that naff it wouldnt have got this far. My Mother is disabled at the hip due to an accident, but loves a workout on the old cycling machine as she used to love cycling, but wont go out on a bike with my Dad in case they go too far and she cant get back. I think the little extra power offered by these pedals is just the ticket for cyclists who may have given up through injuries and ailments and are too proud to take out a tricycle, a recumbant or heavy electric bike (which dont look cool) slap these pedals on one of those Scott Contessas and I bet my Ma would be straight out into the wilderness with the wind in her hair, give this inventer dude a chance, I think there are plenty folk out there stuck in the house who would benefit from these pedals, give them all a chance. Vote yes, anyone who can invent anything to do with a bicycle in this day and age has my vote.

say no to the engine!

sidney's picture

posted by sidney [22 posts]
24th June 2010 - 22:45

3 Likes

I also think Sir Steve Redgrave should consider endorsing these now after his recent cycling catastrophe, they would definately speed up his return to cycling and a full recovery.

say no to the engine!

sidney's picture

posted by sidney [22 posts]
24th June 2010 - 22:59

2 Likes

One could probably spend hours debating the physics and still not come to a conclusion everyone accepted. As there is a prototype and road.cc hope to try it out, let's wait for the report. Given what I have read so far, I think it could well be effective - if this is not so, it doesn't say much for all the assessments its undergone so far.

posted by SteveU [6 posts]
27th June 2010 - 21:32

2 Likes