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zepolen

Hey at last, maybe in my lifetime I'll see the motor per wheel AWD design I've been fathoming for the past ten years.

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Fun fact: The Lohner-Porsche had a gas motor and 4 electric motors; one in each in wheel in 1900.

Cool but not the system I'm thinking of:

A complete real time tweaking of per wheel outputs based on live slip/velocity/momentum for perfect AWD.

AFAIK the Mercedes SLS Electric Drive did that in 2013 https://media.daimler.com/marsMediaSite/en/instance/ko.xhtml...

In addition to the sls this idea is deployed to some extent in IC cars as well: electronic limited slip differentials can send continuously varying torque to each wheel, see the Porsche 918 spyder (combo electric and IC) or the Nissan GT-R which has a famously odd driving characteristic as a result of the computer controlled torque vectoring.

Formula Student Cars have had this for years, check out TU Delft Formula Student Electric vehicle.

Full AWD Torque vectoring.

A Croatian company built two fully electric hypercars with 1 motor per wheel and a torque vectoring system:

Rimac Concept One (the old model):

- Acceleration: https://www.youtube.com/watch?v=eT7KKxoAvvk

- Presentation at Stanford: https://www.youtube.com/watch?v=1FsrgJ66wUw

Rimac Concept Two (the new model, they plan to build ~150 of them):

- Geneva motors show: https://www.youtube.com/watch?v=XvjvYzzBh-k

- Company website: http://www.rimac-automobili.com/en/

We, Rimac, are also supplying Koenigsegg with the battery packs for Regera, feel free to AMA, hopefully I'll be able and allowed to answer :)

Yes, I've been imagining this too since 25 years ago now, also thinking how it would not need turning wheels, just power differential like paddling a boat. Not sure if this part can be done though or if it would break under the pressure... I should have studied engineering to find out.

Chinese lsevs do exactly that. One banal BLDC for each wheel, but more often just two

No steering wheel...that is an interesting idea, I don't think pressure would be a problem, but sensitivity might be.

This is how tanks steer! And also (to some extent) why using them on roads ruins the roads. If you tried in a traditionally wheeled car then all of the drive shafts would snap though!

I used to think that the treads actually ruin the road because it changes to contact surface on which you apply the power differential from a line (on a tire) to a rectangle(the tread), i.e. it tries to rotate a flat surface which can't be rotated, so somethings got to give. Arguably a tire wouldn't have the same problem.

No turning wheels means no parallel parking. Zero turning radius would be cool, but even with complete differential steering that would scrub the tires a bit much. I don't think you could practically remove steering tires entirely. I think you're still stuck with a rack and pinion, ball joints, tie rods, strut bearings, etc so even with AWD with independent electric motors on all wheels differential steering isn't really that useful. On a performance car, it'll help with handling around turns. I don't see that becoming commonplace on average cars because of the added cost.

Your wish is granted: https://www.youtube.com/watch?time_continue=718&v=qeXZs_XAmM...

Woah! Looks like it is. https://doubleapex.co.za/schaeffler-audi-4e-performance-conc...

Why not let the differential(s) distribute the power? I’m sure one or two larger motors is better than 4 small ones.

I would like to see a serious off-road EV.

Afaik big trucks had that for quite some time now.

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