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Unread 15-02-2009, 00:26
Mentor_Mike Mentor_Mike is offline
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FRC #2809 (K-Botics)
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Re: 2809 - Traction Control Demo

Quote:
Originally Posted by FRC4ME View Post
A torque sensor? I never thought of that. May I see which particular sensor you are using?

Anyway, it turns out the torque a DC motor produces is related only to the voltage (effective) you are sending it and the rpm of the motor. We measure the rpm of the motor with the encoder, plug that into the equation, and get back the maximum voltage we can send without causing enough torque to slip.

The beauty of the system is that it involves no PID loops, no tuning, no trial-and-error. We have about 15 measureable constants and 2 measureable variables (battery voltage and motor rpm), but nothing needs to be manually tuned. Yay for physics.
I feel like you'll also need current.... see the power equation.

And no PID? Are you just doing direct drive with a variable cap? (To hold the torque.)
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