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Unread 04-02-2017, 16:28
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cbale2000 cbale2000 is offline
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AKA: Chris Bale
FRC #5712 (Gray Matter)
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Re: 2.5" CIM Motor stops when climbing

Quote:
Originally Posted by serdaruluer View Post
Can we find another solution but using gearbox? On the motor side small gear, on the shaft side big gear possible?
Based on the math I've done you need about a 9:1 ratio between the CIM motor and the spool (assuming a 1" diameter spool and a ratchet strap-style rope) to lift a fully loaded FRC robot with a decent margin of error (stalls at ~277lbs).

The biggest ratio you can get practically with sprockets (at least easily available ones) is about a 5:1. Now that said, at a 5:1 ratio, if you double the number of motors running it (like adding a second CIM to the opposite side of the system) that 5:1 ratio would work just fine.

Ideally though you would want a proper gearbox that will get you closer to that 9:1 ratio.
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Last edited by cbale2000 : 04-02-2017 at 16:30.
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