# 2 hub motor differential electronic ?



## Thomas4200 (May 10, 2018)

Hello,

I make a little electric car, i don't understand what happen when use 2 hub motor and 2 controller (traction or propulsion) who simulate the mechanic differential ?

here is the product I'm talking about

https://fr.aliexpress.com/store/pro...60.html?spm=a2g0w.12010612.0.0.f5477442zCbHQi

Thanks 

Have a great day

Tom


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## Thomas4200 (May 10, 2018)

i have find solution

see here : http://www.diyelectriccar.com/forums/showthread.php?p=997521#post997521


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## Duncan (Dec 8, 2008)

Thomas

The solution to the differential problem is simple

Don't worry about it!

You will have two controllers and two motors - the controllers basically command a current which is a wheel torque 

As you go around a corner one wheel will move faster than the other - no problem

If you lose traction one wheel will speed up - there is usually a max rpm in the controler exactly the same as in a conventional diff - except that the other wheel will still drive the car! - better than a normal car

You will find that you will be able to drive the car with one motor disconnected - and you (the driver) may not even be able to tell

Think about a normal car diff - the only thing keeping both wheels at the same speed in the road


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## brian_ (Feb 7, 2017)

True, if you don't want any control of a spinning tire (and perhaps with very little power there will never be a spinning tire), just asking each controller for the same torque gives essentially the same effect as an open mechanical differential. This assumes that the accelerator pedal signal can be split to both controllers, which is true if it is just a voltage.


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## RIPPERTON (Jan 26, 2010)

Thats correct, you dont have to manually differentiate when cornering.
It all happens naturally.
Watch at 1m 53s I go around a big sweeper in my Mira and jump on and off the gas and there is no reaction in the steering.
The Mira had 2 big hub motors in the front connected to each drive shaft.
2 controllers controlled by one throttle pot and one regen pot.
https://www.youtube.com/watch?v=28noTIX_ceo
Walk around
https://www.youtube.com/watch?v=CfFK6b7812Y
Heres the regen pot cabled to the clutch pedal.
This pot is now the throttle for the kart. Its a throttle pot from a Ford Falcon.
https://www.youtube.com/watch?v=I4oxzwa5NeQ


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