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Unread 09-12-2013, 18:09
Oblarg Oblarg is offline
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Re: Omni vs Mecanum CoF ?

Quote:
Originally Posted by AlecS View Post
Ah, I think I see why I was confused, The initial equation was flipped.
Intial Eq:

(Wf * 2 * pi * r)/S = (40lb * r)/Ts

Eq:

S/(Wf * 2 * pi * r) = (40lb * r)/Ts

This puts actual speed above free speed, and actual torque above stall torque, like you described. The previous version was not giving useful numbers, this one does.

You also need to do some unit conversion there,

If use Stall Torque in in/lbs (21.5);

((S/60)/12)/Wf*2pi = 40lbs/Ts

This equation gives ~23FPS, same as what I got above. This number would appear correct, assuming 0 losses and perfect current supply.
I always let WolframAlpha handle the units for me, because I'm a lazy bum

Well, looks like I was wrong the first time through about a week ago. I figure I probably had a radius in one part and a diameter somewhere else, or similar.
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