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Unread 20-01-2011, 14:42
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VEX Robotics Engineer
AKA: Arthur Dutra IV; NERD #18
FRC #0148 (Robowranglers)
Team Role: Engineer
 
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Re: Calibrating Mecanum Drive

Quote:
Originally Posted by Jogo View Post
I have a question regarding calibration of mecanum drive.

I am comfortable with using the gyro to regulate rotational movement. However, is there a decent way to regulate translational movement? One thing I fear is that each wheel will move at slightly different speeds relative to one another...would the only way to deal with this be to wire up four encoders? Do teams commonly use control loops to regulate wheel speeds?

Thanks in advance for any tips/advice.
All motors are slightly different due to manufacturing tolerances. To combat both this (and any slight differences in friction between wheels), use an encoder on each wheel feeding into a velocity PD controller (PID, but without the I).
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Art Dutra IV
Robotics Engineer, VEX Robotics, Inc., a subsidiary of Innovation First International (IFI)
Robowranglers Team 148 | GUS Robotics Team 228 (Alumni) | Rho Beta Epsilon (Alumni) | @arthurdutra

世上无难事,只怕有心人.