[ausev] hub motor noodling

[MLAB]

I just got my renewed EAA membership card, so I think I will write this 
post that has been on my mind for a while.

I deal with hub motors a lot since my EV work involves bicycles and 
tricycles (for myself or for clients).  I know that hub motors are used 
on electric cars as well, such as that ugly-as-sin but ridiculously fast 
Japanese 8-wheeler that graced the cover of a recent EAA newsletter.

Hub motors have the advantage of not needing a drivetrain, so that 
system can be torn out of the conversion car to save weight and space 
(and drag), but on the other hand that eliminates the multi-gear 
transmission, with its benefits.  However I have a hub motor with 2 sets 
of windings in it, making it a two speed motor, so that ability is not 
wholly lost.

So every time I see a Geo Metro (or the like) sputter past, I imagine 
stripping out the motor and drivetrain and attaching hub motors on all 
four wheels.  The front two motors would be identical, with low and 
medium-low speed windings, and the rear motors would be similar with 
medium fast and fast windings in each.  All four motors could engage at 
low speed for extra torque when needed, but normally only the front 
wheels would drive from a start.  This would give the car 4 speeds, and 
save room on the chassis for batteries.  Some sort of differential would 
connect between the steering sensor and the throttle system.

Of course the rotors (where the wheels bolt on) would have to be 
modified to be stationary, non-rotating, since the hub motor must mount 
to something fixed.  Standard automobile wheels could then bolt to the 
motor.  Since I do not work with cars (right now, at least) I am not 
familiar with the wheel mounts, and the like.  I often get custom motors 
from a Chinese company that could likely make the sort of package I 
need, though I'd have to figure out how to get disc brakes arranged to 
fit up with the calipers on the car.

Anyone ever seen something like this?  Just curious...


-- 
Mike Librik, LCI #929
Easy Street Recumbents
(512) 453-0438
45th and Red River Streets, thereabouts
Central Austin
info at easystreetrecumbents.com
www.easystreetrecumbents.com
www.urbancycling.com