Motor(s) randomly firing in Disabled

[scca229]

We have a strange issue that has been happening since first powering up the bot this year and hasn't gone away through firmware/software updates. I don't know if this is electrical, programming, or hardware....hence choosing this forum.

At random times, couple times a minute or even 10+ minutes apart, we have at least one motor that will activate for anywhere from a split-second blip to up to 2 seconds when the bot is in Disabled mode. Sometimes it happens right when turning the bot on, ie., the RoboRio hasn't even loaded yet. This is the pair of controllers running one side of the drivetrain.

Even stranger is that it doesn't seem to happen at all when the bot is in Enabled mode. I have to attempt to confirm that, but I don't believe it happened after 20+ minutes in Enabled last night after going off many times in the preceding half hour timeframe in Disabled. Since it is so random, trying to see what the LEDs are doing on the suspected pair of controllers is problematic (thinking of setting my phone recording video to try to catch it) but it "looks" like only one of the controllers seems to be doing it.

We are using Victor 888's attached to the RoboRio with Y-PWM cables controlling CIMs. Visual inspection of the connections show no stray copper crossing. All controllers have been calibrated multiple times. Programming done in LabView which I am very green in but the condition remains with the basic zero change tutorial loads as well. RoboRio has also been reformatted a few times with no change.

One more piece of info that may be pertinent, when the bot is turned on (or moved from Enabled to Disabled), the flashing LEDs on the controllers are not in sync. 4 of the 6 flash at the same time (and don't look to be the culprits), the other two flash differently and not in sync with each other either. If the PWM cable is unplugged from the RoboRio for only the suspect pair and then the bot is powered on, they flash in sync with the other 4 (and after 30 minutes, no motors fired off).


Is this a known condition with a known cause or am I chasing gremlins at this point? I am going to try moving the PWM cable to another port on the RoboRio (a new Y and extension as well) and then also swap in the spare controller that we have onboard. I am just curious if anyone saw this condition before. It is very unnerving to have the bot suddenly come alive (although on blocks) when working with it.


Nate