This is a doozie!!!!!

[archiver]

Posted by Tom Wible.   [PICTURE: SAME | NEW | HELP]


Coach on team #131, chaos, from central high school manchester and osram-sylvania.

Posted on 10/6/99 5:35 PM MST



In 1999 our robot had a chronic problem which we were never able to solve. The problem involved the speed control of our main drive system which consisted of Victor speed controllers and the drill motors. When slowly accelerating the robot from a standstill, at about half speed, one side would stop as the other continued to accelerate. If you went to full on both sides the drives would go to full speed. This is how we would compensate. When we bench tested each drive system, they'd work perfectly individually. Never any glitches. It almost seems like the processor is having trouble with the math or something. We run a custom program, but it does it on the default program too.
Has anyone else seen this on thier robots?

Tom Wible
Team C.H.A.O.S.

[archiver]

Posted by Jerry Eckert.

Engineer from Looking for a team in Raleigh, NC sponsored by New England Prototype/Brooks Automation.

Posted on 10/7/99 10:03 AM MST


In Reply to: This is a doozie!!!!! posted by Tom Wible on 10/6/99 5:35 PM MST:



Tom,

Were you ever able to reproduce the problem on the bench with both sides active? Or did it only occur under load (robot moving on the floor)?

Was it always the same side which responded abnormally?

Did you try swapping speed controllers and/or drill motors from one side to the other? Did you have a chance to try swapping the processor?

If you can rule out defective components (including the processor), my first guess would be electrical noise - either induced or RF from a transmitter. A design flaw in the BS2 is a possibilility, but I'd expect the problem would have been a lot more prevalent if that were the case

Jerry

: In 1999 our robot had a chronic problem which we were never able to solve. The problem involved the speed control of our main drive system which consisted of Victor speed controllers and the drill motors. When slowly accelerating the robot from a standstill, at about half speed, one side would stop as the other continued to accelerate. If you went to full on both sides the drives would go to full speed. This is how we would compensate. When we bench tested each drive system, they'd work perfectly individually. Never any glitches. It almost seems like the processor is having trouble with the math or something. We run a custom program, but it does it on the default program too.
: Has anyone else seen this on thier robots?

: Tom Wible
: Team C.H.A.O.S.