Thread: Up the Ramp
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Unread 12-03-2003, 08:07
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Al Skierkiewicz Al Skierkiewicz is offline
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Quote:
Originally posted by Thunder360
how fast were we going then... We were able to switch between high and low speeds by flipping a switch on one of the sticks.
I am afraid you haven't given enough info here to determine what your speed was. How far did you have to reduce the speed in software, what was the low gear ratio RPM?
I can make some assumptions and give you an answer, although as an electrical guy I will defer to any mech engineer who would like to step in. Assuming your original design RPM was 4379, (the normal operating RPM from spec sheet) and that the motors could in fact drive the robot at that RPM. The output RPM of a 6:1 gear ratio would be 729 RPM. Coupled to a 8.5" wheel with a circumference of 26.69" at 729 RPM that is 12.15 Rev/sec times the circumference comes out to around 27 ft/sec. 27 ft/sec is more than double a good speed for both speed and torque in our designs. Most teams seem to go for 8-12 FPS. So you could reduce the size of the wheels or change the gear ratio.
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Al
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