Lag At MAR Champs

Did any other teams attending the MAR Champs today experience any input lag into their controls whilst playing their qualification matches today, specifically whilst on the blue alliance side? We noticed that in 2 out of the 3 matches that we played on the blue alliance side we were experiencing lag that caused us to perform much worse than we should have, and our alliance members seemed to be having similar issues.

What does you DS logs show for dropped packet during those matches.

I’ll check that in the morning.

In 2 of our matches we experienced packet loss and lag on controls.

I’ll ask our drive team and see what they say tomorrow.

If you could upload the .dslog and .dsevents files for the matches with logs that would be helpful.

Happened 1 out of 2 matches on blue side for us. In match 7 I believe all 3 of our alliance members experienced significant lag about halfway through the match. Everything worked as expected in Match 28.

Yeah, we were with you in that match and it got pretty bad.

Did you guys have cameras on your driver station?

I’m wondering if you guys are running into the same problem the field had at Howell.

If you bring up these concerns with the FTA, he/she will be able to bring up field logs to observe what was actually happening in the affected match. With hard evidence in such a form, the FTA would be able to afford a replay for the match if it is determined it could have changed the outcome.

Whether or not the FTA can ‘solve’ the issue moving forward is another matter entirely.

I’ve seen numerous matches with all robots at 6+ mbps with no ill effects. There was only once this year where I saw trip times across the board rise above 20ms. That one match they went to around 120ms. Ironically my team was in that match, and I have no clue the root cause.

@1279, if you post your dslogs (the entire directory as a zip is fine, but please remove all non 2017 files), I can look through them.

EDIT: I have seen in the past that a robot radio was damaged, and instead of running at 300mbps local, it would derate to some slower speed, like 12mbps. I have seen that cause issues in prior years and is a pain to track down. I usually have my laptop in promiscuous mode and use airodump-ng to see everyone’s connection rate when I suspect this is the issue.

This happened to us at Hudson Valley, we never figured out what it was, but it seemed attached to a specific drive station(s).

The lag never returned on the second day so it seems like the problem sorted itself out (hopefully for good).

I’ve seen field at HVR 3 of the last 4 weeks and haven’t noticed any systemic lag issues with the hardware or a specific station. I also don’t remember anyone at HVR letting us know about such an issue - if you feel like your robot is laggy, come track me down in the question box and I’ll be happy to take a look at your DS logs to diagnose the issue.