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Unread 11-02-2014, 18:34
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Re: CIM motors vibrate/jitter

It's probably a race condition in your software. Can you post your code?
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Unread 12-02-2014, 07:33
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Re: CIM motors vibrate/jitter

The LED indication you describe is the Talon responding to a command that takes it in and out of the 4% of deadband condition. Something is commanding the Talons to do that. The Flashing orange is the indication that your are close to the deadband condition and the flashing red is an indication that a throttle command has been sent to the Talon. The LED flashes Red or
Green in proportion to the throttle command sent to the controller.
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Unread 10-03-2014, 13:12
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Re: CIM motors vibrate/jitter

Good day,

I am wondering if any success has been seen on this issue. Our robot is seeing a similar issue with running the CIMs. With a configuration of the driver station without the Xbox controller that runs our drive train, the motors will behave in our Auto-tests. But, after being left on for a duration of time, one, and sometimes two, of our CIMs begins to jitter, and the robot becomes non-static.

If the Xbox controller is plugged in, the error still occurs, and any usage of the controller does not clear the twitch condition.

After a power reset, it seems to work okay, but then it comes back.

I'm suspecting digital cables too close to power lines and is getting a induction that the software can't clear out.

thanks for any input,
WPI in three days !!!

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Unread 10-03-2014, 17:06
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Re: CIM motors vibrate/jitter

Your first step should be to calibrate the motor controllers, as was suggested above, this issue (if you've ruled out code and joystick calibration as sources) is likely due to a PWM signal that is slipping out of the deadband.

Other possible sources are bad ribbon cables from the DSC (with this I believe you would see jitter even while driving) and battery voltage/reset conditions.
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