Quote:
Originally Posted by Fabs
True if the motor was behind the front wheels but it's not...
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Remember that in this case, the motor is fixed rigidly to the rest of the car, so you've got to look at the whole car as a system when you're looking into moments, etc. Consider how a car pivots around its centre of gravity when adjusting a jump w/ the throttle - no matter where the motor or drive wheels are...
A 4-gear system basically lets the turning moment from an accelerating motor add up with the moment from the accelerating drive wheels, as opposed to partially counteracting it.
In either case, the wheels are the big players here - since they're massive and have a pretty big diameter with most of the mass around the edge.
And, the accelerating wheels are definitely working against you if you're front wheel drive, since the weight will transfer to the back since the moment will act on the centre of gravity of the whole car - which invariably is between the axles...
This brings to mind an idea.... since we've now got more power from our brushless motors than we can possibly use, how about building in some sort of counter-rotating flywheel that accelerates in an opposite rotation to the wheels? Hmmm...
Cheers,
Ty