Podbike

[Torslanda]

http://podbike.com/

Innovative? Direct drive pedal/electric. No chain. No gears. No mention of battery capacity.

Holy grail or croque de . . . ?

Wotchafink?

[Kim]

Electric transmission's unacceptably inefficient for a pedal cycle, but that becomes moot when you're augmenting with battery power anyway.  If they do the velomobile well it could be an excellent all-weather commuter for rich Germans.  If not, file under 'Sinclair'.

[ElyDave]

No mention of price, unsurprisingly. Whilst I could see me running the three miles into town with it, Ely to Cambridge down the A10 would fill me with trepidation, and possibly prove that adrenaline is brown.

Can't see much of a rural application when compared with my 20 year old hard tail 26" MTB, or my 15 yo landrover.

[RibbleRouser]

Seems to me that it's a small, slow, electric car with a human powered generator to charge the battery.

[Tigerrr]

I am sure it will as successful as the C5.

[Polar Bear]

Oddly it occurred to me that it was the Reliant Kitten variant of the C5!   

I'd certainly like to see one, to even try one.   No idea if I'd want one until I've done that of course.

I wonder if you can leave the top off in the summer?

[mrcharly-YHT]

4 wheels - why?

So impractical in so many ways. very little luggage space, no way of adapting it to carry children or babies.

[Tigerbiten]

4 wheels - why?

More stable on high speed corners.

[fruitcake]

I think it would be better launched outside the UK, just because of the legacy of that infamous electric-assist recumbent tricycle.

https://en.wikipedia.org/wiki/Sinclair_C5

It's a story of poor quality control and hostile media reviews. Interestingly though, the C5 is now the preserve of enthusiasts, some of whom do things like this: https://en.wikipedia.org/wiki/File:Sinclair_C5_jet_engine.jpg

[Cudzoziemiec]

So you pedal but instead of the pedals driving the bike quad? quike? pedal car? four-wheeled vehicle, they drive an electric generator which powers motors in the rear wheels. Presumably the battery stores enough energy to provide extra power for hills. At least I hope it does – I didn't notice a weight given but it must be rather a lot. It looks to me like a toy for people who fancy high-tech, complicated solutions as ways of avoiding simple problems (and pretending to be greener than they really are).

4 wheels - why?

So impractical in so many ways. very little luggage space, no way of adapting it to carry children or babies.

It does say "Room for bringing a child within the cabin" but whether that includes any kind of baby seat it does not specify. And I'm sure Auntie Helen has extolled the luggage capacity of her velomobile.

[Mr Larrington]

I think it would be better launched outside the UK, just because of the legacy of that infamous electric-assist recumbent tricycle.

https://en.wikipedia.org/wiki/Sinclair_C5

It's a story of poor quality control and hostile media reviews. Interestingly though, the C5 is now the preserve of enthusiasts, some of whom do things like this: https://en.wikipedia.org/wiki/File:Sinclair_C5_jet_engine.jpg

ITYM "Poor quality control, hostile media reviews and being shit.  The single very low gear (33" IIRC) was bad enough, combine that with the complete lack of adjustment for leg length and you got something well-nigh useless once the battery ran out of voles.

[fruitcake]

Yebbut the C5 is ideal for "shopping, commuting and other short trips" (as long as you won't need to travel more than 20 miles in a day), and it weighs only 30kg (45kg with the battery) 

Unless, like this chap, you modify it, which takes it to a whole other level 



http://metro.co.uk/2012/04/03/plumber-spends-1000-transforming-dud-80s-invention-into-a-monster-trike-375411/

I'm not sure what that's ideal for, but he looks like he's having fun.

It's the juxtaposition of 'naff' and 'ridiculously butch' that makes me chuckle.

[Kim]

So you pedal but instead of the pedals driving the bike quad? quike? pedal car? four-wheeled vehicle, they drive an electric generator which powers motors in the rear wheels. Presumably the battery stores enough energy to provide extra power for hills. At least I hope it does – I didn't notice a weight given but it must be rather a lot. It looks to me like a toy for people who fancy high-tech, complicated solutions as ways of avoiding simple problems (and pretending to be greener than they really are).

Don't think of it as a pedal cycle with an electric drivetrain (that way lies madness).  Think of it as an electric-assist cycle with all those troublesome (and in a velomobile, annoying to get at) oily bits eliminated.  Weight and rolling resistance is largely irrelevant when there's a motor providing the power, unless the weight is badly distributed and affects handling.

"Ohnoes!  What if the battery runs out!" isn't an issue any more than any other motorised vehicle running out of energy: You plan your journey accordingly.  The ability to limp home inefficiently under human power is a bonus extra feature you should never have to use.

Similarly, you have to compare it to other velomobiles general practicality wise.


The real question is "Is it shit?"

[Cudzoziemiec]

So how does it work? They say there's no chain etc, there's no direct connection between pedals and wheels; your pedalling generates voles for the motors in the rear hubs. It complies with pan-European legislation they say, which means no pedalling = no voles, so you have to pedal all the time; you can't just cruise on batter power. Of course it could well be that the batter provides 90% of the power. So "is it shit?" might come down to "what's the battery capacity?"

[mrcharly-YHT]

The real question is "Is it shit?"

Well, since the 'designer' hasn't even built a prototype, I'm going with 'yes'.

[Kim]

So how does it work? They say there's no chain etc, there's no direct connection between pedals and wheels; your pedalling generates voles for the motors in the rear hubs. It complies with pan-European legislation they say, which means no pedalling = no voles, so you have to pedal all the time; you can't just cruise on batter power.

Yes, but the power generated at the cranks doesn't have to be the power put out by the motor.  The turning of the crank generator can be used as a control signal in place of the usual crank rotation, hand throttle and/or torque sensor.  That it's also providing some power to top up the battery doesn't affect the usual e-bike functions.

Consider a pedelec with the chain removed:  Rider twiddles pedals, CRS says pedals are turning, motor runs.  (The chain's required for legal compliance, but not to make the system work, unless the sensing is all done at the hub.)

Of course it could well be that the batter provides 90% of the power.

Exactly.  Or some other value, depending on how you want to ride it.  I can imagine 50:50 on the flat going to 95% battery on climbs, for example.  Presumably at some speed the linear losses from the electric drivetrain are cancelled out by the aerodynamic advantages of a full fairing, but possibly not at legal power levels.

So "is it shit?" might come down to "what's the battery capacity?"

Battery capacity determines whether it's suitable for a given journey (or vice-versa), but it's entirely possible for it to be shit irrespective of battery life.  That it's coming from a 'designer' rather than an established maker of velomobiles rings the alarm bells there.

Obviously if the battery capacity's too small for the trips you want to do, then you won't be buying one, but that goes for anything.  Nobody in their right mind buys a pedelec intending to ride around on a flat battery.

[Cudzoziemiec]

Ok, the description on the website had given me the impression that the rider's feet acted on the generator as steam on a turbine at, er, Didcot. Or not Didcot. Didnot? Notcot? So there needed to be some mechanical connection between cranks and generator – I envisage a couple of cogs between BB and generator shaft, like a much simpler version of a motorcycle crankshaft and gearbox unit. I was also under the general impression that 'pan-European legislation' (I wonder how much of Europe it actually covers?) required that electric power not exceed a certain percentage or multiple of the power (torque?) at the crank.

[Kim]

Ok, the description on the website had given me the impression that the rider's feet acted on the generator as steam on a turbine at, er, Didcot. Or not Didcot. Didnot? Notcot? So there needed to be some mechanical connection between cranks and generator – I envisage a couple of cogs between BB and generator shaft, like a much simpler version of a motorcycle crankshaft and gearbox unit.

I don't know about the mechanical specifics, but I'm picturing a crank-driven genset that's completely independent of the drive motors.  Some hand control to select  a) how much electrical power the genset makes at a given crank speed (ie. crank resistance) and  b) how much power the motors give at a given crank power - probably wrapped up in some clever user interface that abstracts it all out to a "how hard it is to pedal" control.

I was also under the general impression that 'pan-European legislation' (I wonder how much of Europe it actually covers?) required that electric power not exceed a certain percentage or multiple of the power (torque?) at the crank.

Not something I've come across.  There's a power limit and a speed limit, and the pedals have to be turning, but within that anything goes.  Most systems don't measure power/torque at all, and only know that the cranks are rotating (usually just sensing direction, not cadence).  Power is typically set by a hand control.  Torque sensor systems like barakta's apply power proportionally to force at the pedals (well, actually hers applies a function of force and cadence, in an attempt to do a better job when twiddling up hills in low gears), but still have a mode where they give you full power as long as the pedals are turning, for climbing bastard hills.

Barakta's trike can be ridden^[1] on electrical power alone, by pedalling lightly enough not to engage the freewheel.  This will happen  a) when the programmed minimum power is enough to keep things rolling along at modest speed on the flat  and  b) in bastard hills mode.  The former can be avoided by setting the motor power control to zero, but has come in handy in a couple of painful hip incidents.


_{[1] Though not started from stationary, due to a software parameter for minimum road speed before the motor kicks in.  Makes things more predictable.}

[Cudzoziemiec]

"Crank-driven genset". Right, yes, so if you're not pedalling, no power generated and nothing to the rear wheels.

[Efrogwr]

Maybe it has over unity motors . I've seen a few posts about such magic machines lately, one project raised money via Indiegogo… then disappeared.


This looks like an industrial designer stylist with a new graphics suite, who's doing a bit of kite flying.

[jsabine]

Yebbut the C5 is ideal for "shopping, commuting and other short trips" (as long as you won't need to travel more than 20 miles in a day), and it weighs only 30kg (45kg with the battery) 

Unless, like this chap, you modify it, which takes it to a whole other level 



http://metro.co.uk/2012/04/03/plumber-spends-1000-transforming-dud-80s-invention-into-a-monster-trike-375411/

I'm not sure what that's ideal for, but he looks like he's having fun.

It's the juxtaposition of 'naff' and 'ridiculously butch' that makes me chuckle.

Yes, well, that's Colin Furze. He has form. The article mentions his 70mph mobility scooter, but he's also created a jet-powered Raleigh shopper and built his own Wall of Death.