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Unread 05-10-2013, 17:31
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Re: FRC Blogged-Kit of Parts Drive System Option

Quote:
Originally Posted by Ether View Post

Does anyone know where the 81% number came from?



If I remember correctly, I once read a really, really old CD thread that said 81% was determined by taking one of 229's drive bases, running it to top speed, and measuring that speed. Ratio of that top speed to actual speed became the default "speed loss constant". I'm sure this number is somewhat correlated with efficiency, wheel size, tread type, etc etc. For most practical purposes it's "good enough".

Efficiency in JVN's calculator is used to calculate motor loading, not speed.
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