Thread: Motor Bias
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Unread 31-10-2005, 19:02
gshosford gshosford is offline
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FRC #1293 (D5 Robotics)
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Join Date: Apr 2005
Rookie Year: 2005
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Re: Motor Bias

Quote:
Originally Posted by KenWittlief
Where they both faster going 'forward' on your robot? most bots have the motors mounted so one is running cw and the other is ccw when the bot goes forward.

I wonder if its the motors that are biased, or your drivetrain. If both sides run faster in the bot-forward direction, I would say its your drivetrain.

also, it would really help to measure wheel RPMs. Basing your estimate of speed on how the drivetrain sounds can be very misleading.
With the joystick in the full forward position, the right motor, for sake of explanation, was turning faster than the left motor. With the joystick in the full reverse position, the left motor was turning faster than the right motor.

This surprised both of us that were working on it because all the discussions state that the CIM has virtually no bias.

The observations were visual not audible. We could see that one motor was turning much faster than the other motor.

Mike Betts' response with the link to the free-speed data was helpful. Does anyone have the stall torque data?