
Reinventing the Wheel to Power Electic Vehicle Future - rmason
https://www.jpost.com/Israel-News/Israeli-firm-truly-reinvents-the-wheel-to-power-electric-vehicle-future-595083
======
azinman2
This was first proposed at the MIT Media Lab in partnership with GM about 10
years ago:
[https://www.media.mit.edu/projects/citycar/overview/](https://www.media.mit.edu/projects/citycar/overview/)

~~~
Someone
That may have been the first to combine steering, suspension, and powering,
but I wouldn’t bet on it. “In-wheel” motors are a lot older.
[https://en.wikipedia.org/wiki/Wheel_hub_motor](https://en.wikipedia.org/wiki/Wheel_hub_motor):

 _”Wellington Adams of St. Louis first conceived of building an electric motor
directly in the vehicle wheel, though it was attached via complicated gearing.
The Adams patent is U.S. Patent 300,827 in 1884.”_

It even mentions an in-wheel Diesel engine.

------
cr0sh
Looking at this illustration (something I found via googling "REE motor
wheel"):

[https://imgur.com/8iAOOAG](https://imgur.com/8iAOOAG)

...which was linked off of:

[https://newatlas.com/ree-modular-mobility-
platform/60486/](https://newatlas.com/ree-modular-mobility-platform/60486/)

It appears that the motor and gearbox are outside of the wheel, not an
integrated part. Then there's a flat plate, then the wheel (that plate also
seems to limit ground clearance).

It's nice that it's an all-in-one package, I guess - but not what I was really
expecting (with the motor integrated into the rim, possibly the suspension
being part of the wheel via sprung spokes or something).

While it would be great to have everything "in the wheel" \- leaving tons of
room for occupants and/or batteries on the chassis (not to mention fewer parts
to wear) - the issue has always been how to cope with "unsprung weight" \-
which can lead to handling issues and "bad feel".

It might be possible (as my ideas noted above) - but it would require an
almost complete rethinking and design of what a wheel, suspension, and motor
should be; virtually the whole unit would need to be rethought - and my guess
would be that the wheel/rim would essentially be a "rotor" in some fashion
composed of "sprung segments". That rotor would either be some kind of PM
structure (with the drive coils on the spindle/axle the rotor/wheel would
rotate around), or it would be some kind of "squirrel cage" shaded-pole AC
motor or something like that. There would likely need to be gearing
incorporated to increase the torque, unless the motor could be designed to
take tons of voltage and current (how to dump the heat generated?).

All things well outside my knowledge area, though.

~~~
marsokod
And even if you do all that, you are placing an equipment that is fairly
expensive into one of the worst environment of a car: next to the ground,
lot's of shock and vibration, even higher thermal changes, water and other
liquids in very close proximity. These were also the reasons why the Smart
ended up with a classical design.

Wheels need to be somewhat expandable otherwise you increase your cost. And
what happens if you have a flat, has the spare wheel got a motor as well?

