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Unread 15-08-2005, 18:41
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Karthik Karthik is offline
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Re: pic: 2 speed dogshifter

Quote:
Originally Posted by sanddrag
EDIT: I'd prefer not to work with any fancy spreadsheets for the purposes of my questions to you. I'd just like to see how you came up with the 742 rpm. Thanks.
From what I gather, here's how the 742 rpm was achieved.

Initial Reduction: 12:60 -- 0.2
Second Reduction: 60:30 -- 2.0
Sprocket Stage: 10:24 -- 0.083
Total Reduction = 0.2 x 2.0 x 0.083 = 0.167 (1/6)

Wheel RPM = Motor Free Speed * Reduction * Drivetrain Efficiency
= 5500 * (1/6) * 0.81
= 742.5 RPM

EDIT: Hognabbit, John beat me too it...
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:: Karthik Kanagasabapathy ::
"Enthusiasm is one of the most powerful engines of success. When you do a thing, do it with all your might. Put your whole soul into it. Stamp it with your own personality. Be active, be energetic, be enthusiastic and faithful and you will accomplish your object. Nothing great was ever achieved without enthusiasm" -- R.W. Emerson
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Full disclosure: I work for IFI and VEX Robotics, and am the Chairman of the VEX Robotics and VEX IQ Game Design Committees
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Last edited by Karthik : 15-08-2005 at 18:43.
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