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Old 11-06-2014, 03:28 PM   #1294 (permalink)
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Originally Posted by e*clipse View Post

The basic "open" differential is really a torque split device that is supposed to evenly divide the available torque between the left & right wheel in a corner. The speed and speed differential is not important. This all works fine, until one wheel looses traction, and all the torque goes to that wheel.

So, now look at the simple dual AC motor drive setup: Again, the torque is evenly split between the left & right wheels, as requested by the throttle. In a corner, that is just fine, as the speed & speed differential don't matter. If one wheel looses traction, it is actually BETTER than an open differential, as the wheel with traction will still get its proportion of the torque.


- e*clipse
First thought that comes to my mind is powering into a corner with both wheels trying to do the same speed independent of the other. If the steering is compromised in any way you will go where the motors tell you to go which is straight. Think tank type steering.

A traction device in a differential is the way I will go over trusting any form of code to get it right. All you need is one bad rainy day and you could spend the rest of your life in a wheelchair or worse.

Now that being said I know there will come a day when wheel motors will be the new thing and the control devices will get so good that the mean time between failure is a moot point but why make something that complex when a simple mechanical device will do it right now the right way every time.

Use the sensors already in place to manage wheel spin or Rev limit the electric motors so they don't blow up when a wheel slips and simply let go of the throttle.

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