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Unread 02-01-2016, 22:04
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Re: 6 CIM robo-rio brown out

Quote:
Originally Posted by GeeTwo View Post
In our experience, you will definitely notice. This is what happens:
  1. The current draw causes the RIO to "brown out" the motors.
  2. The voltage recovers.
  3. The system restores the motors.
  4. The motors draw inrush current.
  5. Return to step 1.

This results in a very distinctive "stutter" at about 15-20 jitters per second that gets the robot nowhere fast.
I don't disagree that this is what happens in the really badly wired / really badly geared / really old battery cases, but I don't think this is the normal case. Certainly, our robot didn't experience that in real competition (although did in extended pratice). Rather the robot gets started moving, browns out, and starts again, however since there is already motion, the inrush current is less and it breaks the loop.
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