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Unread 04-11-2013, 21:40
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Re: Shifting Gearboxes

Quote:
Originally Posted by Andrew Lawrence View Post
From JVN's Acceleration calculator, I've found a speed of around 16 ft/s gains the largest time loss to travel a set distance when using 6 motors instead of 4 (Shaves off about a half a second on average). As you get further from 16 ft/s in either direction, the time difference to travel a set distance between 6 motor drives and 4 motor drives gets closer and closer to 0.
While this may be true in certain situations, there are many factors at work here. When you factor in battery and total circuit resistance, friction (static and kinetic), rolling resistance those numbers start to vary dramatically.

Using my own calculator, which incorporates math based on Ether's Voltage Drop model, I could shift the "ideal" speed you're talking about with relatively small changes. 5lbs difference in rolling resistance or a less than perfect internal battery resistance each shifted this number by +-2ft/s.

TL;DR the 16ft/s number could be correct in some situations, but there are simply too many variables at work here to conclude that it would be correct in all situations.
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