Thread: CAN reliability
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Unread 15-07-2010, 23:22
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Re: CAN reliability

Quote:
Originally Posted by Radical Pi View Post
Is the problem following the Jag or the ID (as in try switching it so the code sends the rear commands to the front motors)

Are you sending trusted SET messages every 100 ms? If a jag doesn't receive one every 100ms it will disable itself



Read EricVanWyk's message above your's. I just asked the same thing (It's referred to as trusted mode in the C++ code).
Trusted SET messages every 100ms? You mean these jaguars effectively have TWO heartbeats?
The problem follows the motor controllers around, regardless of whether they are front or rear.
However, i haven't tried rerouting the CAN bus in a different sequence.

UPDATE:
I'm connected to the robot directly over ethernet, and have the driver station running on my computer. I'm not having any issues.
This means it probably has something to do with timeouts; the delay of running live on a computer over wireless was apparently enough to disable one of the Jaguars?

UPDATE 2:
I happened to try unplugging one of the Jaguars, and then plugging it back in. It created some errors, caused some watchdog expirations, and would no longer run. I didn't realize that once a Jaguar is lost, it's gone until you restart the code. I'll see what I can do to fix that.
(It probably just has to do with the encoder and PID settings being replaced)
I'm also going to try to programmatically determine when the Jaguar is not doing what it should. (If the watchdog is alive and a nonzero output setpoint is being sent, and the output setpoint of the controllers is zero, then that motor is disabled and needs to be reenabled.)

NOTE: I've changed this message several times. Please reread if you have not since 9:33.
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Last edited by kamocat : 16-07-2010 at 00:37.
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