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Unread 07-02-2008, 01:37
Mr. Freeman Mr. Freeman is offline
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AKA: Kellan
no team (CSM Robotics)
Team Role: Programmer
 
Join Date: Jan 2006
Rookie Year: 2005
Location: Colorado
Posts: 198
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Interesting victor failure

Today was going to be our first day for driving practice on the robot (which we have somehow managed to finish before ship date). Previous to today, the robot was complete enough to drive, operate pneumatics, etc. The electronics functioned correctly.

Well, we take the robot to an open area and get it there by pushing it. I turn the robot on and push the joysticks forward. It drives about 5 feet and then we hear POP! POP! and see 2 bright flashes. I hit the E-stop button but it doesn't kill the right-side track. (Good thing we mounted the main breaker in an accessible place).

Long story short, one of the victors got fried and always supplied power to the drive motor it was connected to even when it had no signal from the RC. I unplugged the power to the RC and turned the robot on, the right side track still spun. ALL of the victors had the flashing yellow LED indicating that they had no signal.

After analysis, we find that 3 of the black things with the 3 leads coming out of them attached to the victor (are they called mosfets?) blew holes in themselves.


Has anyone heard of a victor failing this way? I was under the impression that the victors would supply no electricity if they were damaged and not working. Also, is it possible that pushing the robot (and thus supplying electricity back to the victors) caused this one to fail? We've never had problems with this in the past.

EDIT: We did double-check that everything was wired correctly both before and after this happened.
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