8 replies to this topic

[mariner]

From the UK autocar web site 

 

https://www.autocar....xtender-hybrids

 

As the developers admit it is not new and sort of obvious but Continental is seious automotive supplier 

 

[cbo]

From the UK autocar web site

https://www.autocar....xtender-hybrids

As the developers admit it is not new and sort of obvious but Continental is seious automotive supplier

Wonder how such a device (in-wheel motor) would take to potholes, kerbs and speed bumps taken too fast? I.e. things that knock your rims silly.

Not that it happens often, but if it does and the engine suffers, it could be expensive.

[Greg Locock]

Dozens, if not hundreds, of solar cars have been running wheel motors for 19 years. I was lead mechanical engineer on that, with young Howard doing the complicated bit, and Vlad doing the proper drafting.

 

The Autocad on p2 is my original packaging layout, when we thought we were going for magnesium wheels. https://ia801606.us....ation Sheet.pdf

[mariner]

Being a complee electrical enginering dumbo does the much lower rotational sped of a wheel motor ( as in Greg's design drawings ) affect its torque, power to weight ratio and efficiency please?

 

 

ps Like many ideas hybrids with electric wheel motors are not new !

 

https://newsroom.por...wer output of 1

Edited by mariner, Yesterday, 09:06.

[Greg Locock]

98.4% efficiency says that isn't an issue. Whether you can get the power and torque is a separate question, I don't know how to cram in more bigger wires neatly, although I suppose you  aren't really voltage limited either. Until we built them cooling was always an unknown, we thought we'd be ok but that was more of a guess than the result of any analysis. 20W say inside a wheel sized object seems like small beer.

[jcbc3]

Didn't Ferdinad Porsche's first ever car feature electric hub motors?

 

 

[edit]

yup

https://en.wikipedia.../Lohner–Porsche

[/edit]

[Bloggsworth]

Unsprung weight anybody...

[GreenMachine]

Looking at those monstrous wheels I see on cars today, is that a problem, or at least, is that the problem it used to be?  Or, the problem we thought it was?

 

Bearing in mind that is related to a ratio, the wheel is a part of the ratio, what has the weight of cars, and specifically BEC cars, done (gone up of course!), so maybe the status quo remains - the ratio now is pretty much where it always was?  Or has damper technology made the 'unsprung weight' bogeyman go away?

[Greg Locock]

Separately Damien Harty and Lotus were asked to investigate this by a wheel motor manufacturer. Luckily (?) they both came up with the same answer, very high unsprung mass is bad, and so is very low unsprung mass, for different reasons. Personally i'd be far more worried about exposing expensive bits and bobs to the accelerations see by the wheel in pothole events etc.