Thread: Robot Twitch
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Unread 26-02-2012, 22:16
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Robot Twitch

Symptoms: Every once and a while (especially after the robot has been running for a while) the robot (usually the drivetrain) will twitch. The drivetrain doesn't really go anywhere but this freaks some people out.

I first though that this was some sort of drivetrain code problem but I couldn't find anything that might cause this?

My current diagnosis is that the cRIO is being bogged down with processing tasks (we are running encoder PID in periodic tasks in a 50ms Timed Loop). I would have initially suspected that the cRIO could handle this OK, but when I put the loop in a diagram disabled structure, the problem stops.

Another symptom is that we sometimes have laggy controls. Generally, at the beginning of build sessions, the robot performs fine (no latency problems), but then as we progress throughout the day, the delay gets greater and greater until everyone gets frustrated and leaves). Why does this happen?

I would really appreciate some help here.
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