Discrepancy at Chesapeake, Israel, Waterloo?

[smtoney]

Speaking for Chesapeake:

As one poster on line mentioned "However, in this case, I think it's pretty fair to say you've simply found the tails of the curve. Someone's got to have the highest and lowest scores, after all." I'm even more surprised that Boston, San Diego and Florida had exactly 50/50 splits. (And Boston is where our field was before us!)

Look at the data this way as well. For the 31 regional's where there was a difference 13 of them the difference went to red. Exactly what one would expect from a normal distribution.

Note: that the eventual winning alliance in eliminations played quarters
and semis on blue and was 4-0 on blue.

One of the FTA's present and the Field Supervisor have both e-mailed me to indicated that they felt there was NOT a universal problem on Blue 2. One of our official scorekeepers was keeping independent notes and link failures were pretty evenly distributed over the 6 positions.

To really point to a single station you would need to have the points scored by robots by match to see if there is an anomaly. Take it from me (and my major was Mathematics), what we have here is too little data being stretched to far. Plus using the data published does not account for results changed due to penalty's, and we had at least two that I recall.

Not to belabor the point, but I don't see a statistical discrepancy. And certainly not one that points to a single driver station. Not with this data.

[Nuttyman54]

Originally Posted by smtoney

Speaking for Chesapeake:

I'm even more surprised that Boston, San Diego and Florida had exactly 50/50 splits. (And Boston is where our field was before us!)

Which came from Manchester before that. Both regionals had numerous replays for field errors. I recall that Boston was going to replay matches 44 through 50 at one point, but some of them were declined by the affected alliance.

This is not to say that the replays are the reason for the 50/50 split or anything of the sort, simply that the field at Chesapeake came from two regionals which had major problems with the system.

[Galum]

Not sure if someone mentioned it already (yes I'm too lazy to read through the thread), but Israel had the same communication problem with the central blue outpost. Not with every robot, but throughout the competition we experienced several incidents with this particular outpost.

I'd like this to be confirmed by a judge/FIRST personal as I was mostly in the Pit area.

[kjohnson]

Originally Posted by Dmentor

The field crew and referees were fantastic at NASA/VCU (well actually pretty much everything was awesome at NASA/VCU except getting beat in the semifinals again). They were helping to fix problems all regional long. When 1908's gaming adapter had to be replaced before the quarterfinals, Kyle patiently confirmed the configuration and assured us that he would do everything possible on the field to ensure that they were working properly. And he did, thanks Kyle! While 1908's robot was immobile for nearly all of QF 4-1, I'm convinced it had nothing to do with the gaming adapter.
...
Thanks so much to the NASA/VCU crew for ensuring that all the teams had the best possible opportunity to shine!

Thanks! I'm glad your alliance was able to advance through 1908's problems. They linked with the field during QF4.1 but did not move. They reprogrammed before QF4.2 and never had another issue.

Originally Posted by ColleenShaver

I do think the efforts of the NASA/VCU field crew should be applauded! It's great that they were able to support so many teams and still run a timely event.

Thanks! We were just as surprised as anyone else that we were able to finish on time. At some points, we were even ahead of schedule. For most matches, the field was reset and robots in place before Jeff began announcing teams.

Originally Posted by bandducky511

Good job on making it to semi-finals! I remember going against your bot in Q38. It started during autonomous at the outpost and did move; however, it stopped moving after our alliance partner collided with your bot. There was a huge collision with 3-4 robots around that outpost that match (if I remember correctly). The immobile part may have been caused by the collisions :S
Also, the DS does not need to be enabled or disabled. However, before you turn the robot on make sure it is disabled or enabled and on tele-op. The field judges are supposed to automatically turn each driver station on disable and autonomous at the beginning of each match (from what I have seen)

Yes, that collision caused the communication issue. It showed immediately on the Field Monitor after the collision.

As for enable/disable, until the scores from the previous match are committed, the next matches driver stations are enabled. When the team numbers change to the current match, the DS is disabled. There were a few instances where some robots on the field had already booted and their motors jumped for a split second when the field switched matches.

Originally Posted by pitzoid

WGA is ~15 seconds to boot
DS is 10 to 20 seconds depending on how fast it identifies its USB devices
cRio can boot in as fast as 10 seconds (what I've seen in the shop, mine don't have a bunch of user code in them though)

I've seen WGAs link with the field AP in <2 seconds, and then I've seen them take as long as 20 seconds in the field, and I've seen some that don't link at all

At VCU the DS took typically less than 20 seconds to boot. As long as the DS has booted, it took about 30-40 seconds for each robot to sync with the field (from power on, to confirmed communication).

[Killraine]

A couple notes on the data I posted:

1) It is data from the qualification matches only.
2) It was not intended to prove that there were problems at any regional. I noticed this discrepancy and merely posted the data to stimulate some discussion.

I have a question though, after reading through this thread. What can a team do when they have a pre-match checklist, go through and make sure everything is plugged in and it all checks out, and then get on the field and can't establish communication? I know this was the case for our team in our last qualification match at station Blue 2. The "solution" was that our robot was disabled before the match and the match was played. In fact, the field team at Chesapeake seemed to be assuming that communication problems were robot-side. Our team couldn't do anything to prevent and/or fix the problem and the people running the field can't be expected to troubleshoot every robot that can't establish communication. What can we do in this kind of "no-fault" situation that left all of the students on our team feeling dejected and helpless?

Also, if anyone has comprehensive scouting data for the Chesapeake event, I would like to take a look at it. I would need the points scored by individual robots (not teams, would like to eliminate HP points) correlated to a match number. From there, I could look for correlation between non-functioning robots and the station they were at.

[Rick TYler]

Originally Posted by rcflyer620

One thing I found that was fairly consistent was the flat black ethernet cable provided in the kit was problematic. teams that had swapped it out for real twisted pair ahd almost no problems with communication.

I know I'm late to this thread, but the FTAs at Seattle must have replaced a zillion Ethernet cables. That and telling teams to plug batteries into cRIOs seemingly took half their time.

[Rick TYler]

Originally Posted by Killraine

the field team at Chesapeake seemed to be assuming that communication problems were robot-side. Our team couldn't do anything to prevent and/or fix the problem and the people running the field can't be expected to troubleshoot every robot that can't establish communication. What can we do in this kind of "no-fault" situation that left all of the students on our team feeling dejected and helpless?

I am NOT an FTA, but I did sit next to them for three days. They can do a lot more than assume that it's a robot problem, since their control console sees lots of information on the field and the robots. I heard FTAs telling teams that their main batteries were low, that their driver's stations were flaky (replaced on the spot), that their radios weren't working right (replaced on the spot), and that they had bad Ethernet cables (replaced on the spot). I was really impressed with how much they knew. Only when the radio link was working, all the monitored on-board components were reporting OK, and the field was reporting OK did I start a match with a motionless robot. For what it's worth, the problems weren't spread out -- it was the same handful of robots over and over again.

I am very sympathetic to your plight (kids on my teams have failed to start in a finals match three times in the last two years), but I don't know what else the field crew can do when all the diagnostics are reporting "Good" but the robot doesn't move. I DO know that the FTAs in Seattle sometimes spent five minutes trying to get a single robot working before some matches, and were always disappointed when a 'bot DNS'ed.

[Rick TYler]

Originally Posted by JohnBoucher

Is this by direction of the GDC or a local decision?

At Seattle the FTA assts would either fix it or allow the team to fix it -- all the way through the tournament. The only time we bypassed a robot is when no one could figure out how to get it running in a reasonable amount of time (a couple or three minutes). We still finished on schedule, so you don't have to be harsh to run a tight event.

[Mark McLeod]

We used the Chesapeake field on Long Island after you were done with it. Now it's on it's way to Atlanta.
Blue 2 was indeed very, very slow to link up, and we spent a lot of effort making sure whatever team was in that spot got cabled up as quickly as the field was ready.
With that said, however, Blue 2 was not the cause of any failures during a match, and I paid particular attention to that station. That doesn't mean teams didn't blame it, because it was out of the ordinary and that always makes people suspicious and quick to blame.
The delay in linking up did finally go away when I swapped out the Blue controls for another reason.

The FMS worked every time. That doesn't mean we didn't find cause to swap out cables, have robots slow to connect initially, or pour over the field stats. With every robot failure during a match I was able to identify a root cause and have the team correct it in time for their next match. Team's were still accusing the field of course, but every one of them found what I told them to look for when they got back to their pits. It pays to follow up with each team and then stand with them the next time they have a match. Troubleshooting the field is a psychological as well as a technical exercise. It means talking with each and every team, finding out what they were doing when the robot stops moving, what they last worked on in the pits before the match. Wires pulled out when a cover was shut, batteries with bad cells signified by precipitous drops in voltage by multiples of 2, a cRIO reset itself only once, robots that ran off on their own and stopped responding to the driver, loss of power, DB9's knocked out of drive stations unnoticed, Watchdog's going unfed or worse on the hairy edge of flickering between enabled and disabled, radios going dead or intermittent during a match.

Troubleshooting is an engineering exercise and it pays off big to keep a clear head and not blame unknowns, such as the field, or assuming it couldn't be your robot. That only blinds you to discovering the cause and correcting it. It's also very important that the field crew not randomly throw out blame, but investigate everything about the field that they have control over. I stopped some of our crew from automatically blaming the radio when robots can't link with the field. If you can't positively identify a cause, even if it's by progressively and systematically replacing cables and black box components, then don't tell teams it's the fault of xxx! I worked the WPA at another regional and the field would sent robots back to us blaming the WPA. Not once was it the WPA, and that misdiagnosis undermined the team's confidence in the field personnel. We organized differently at SBPLI. Whenever a robot had communication issues that couldn't be resolved on the field during Practice Day it was just sent to software inspection. In the heat and passion of the competition analytical thought sometimes gets left behind, but that's where it serves you the most. I do still have one team insisting that that it couldn't be their wiring, because they hadn't touched it, so it had to be the field. Even though other mechanisms on their robot were operating fine and only their two drive Jaguars were giving the "no pwm" blink. They're still speaking to me only because they won .

We didn't start a single match at SBPLI without every robot in place and communicating with the field (except for one robot who missed a few matches after they burst into flames...). We did a lot of team training throughout Friday, beginning with the queuers checking for plugged in bridges and making sure the drive teams plugged in when they were told, the field crew making sure the robots were promptly powered up, the tech crew running around troubleshooting non-communicating robots. Driver Stations were dead when they arrived on the field, but we quickly swapped them out with spares we held ready. None died during a match. That doesn't mean teams still didn't forget to turn their robots on, or plug their bridges in, or even completely forget their battery at least once. Yes, we sometimes picked up after them, but we didn't disappoint all those other team members who worked hard for this single event they're able to attend this year.
We were running 5 minute turnarounds and had to slow down to 6 minutes to give the scores time to post. We were able to deliver 11 matches and the solid performance of the field (along with terrific scorers, refs, field reset, queuers, and of course the teams themselves) is what made that happen.

[mtaman02]

Just to elaborate on what Mark has said thus far which he mostly covered everything in great detail...

As the FTAA of the SBPLI Regional we had approached a different kind of sequence then what FIRST had suggested (won't go into details on that). After we seen that we could easily shave a few seconds to a couple of minutes off on this somewhat new sequence the next thing "I" looked for was immediate connection between Robot <-> DS Robot <-> FMS DS<-> FMS. Once I got a green light on my screen that everything is linked the "tree" would also simultaneously green up. After that I started looking for Battery Voltages and Connection Stats and noted anything that would / had caused a team to stop dead in the match throughout the entire match... (some of you noticed me coming to talk to you b/c of low voltages / no voltage reading or some other form of tech advice besides what Mark would have also said)... To my understanding unlike the previous system, this system here can drain a battery well and still keep communicating but too avoid getting to that point as soon as the voltage dropped below 10 1/5 vdc and consistently dropped or steadied out I cautioned the teams to change out the battery for a charged one. With loads of help from Mark and Bharat I was able to give them an exact error that I seen whether by looking at the screen OR looking at the team and their robot themselves. They promptly went over, investigated and solved in a timely manner.

Yea we did have a robot sit dead in the water by disable and if I'm not mistaken it was a DS E-Stop error or Automatic Disable when the match started [Don't remember which one], we had hard reset the DS and Robot to try and fix this... After running a back to back match after the error had occured the team ran fine. Whether it was FMS or the Field Monitor lockup I cannot say only b/c to much stuff went on during the match reset. Aside from that the only other robot to miss matches was indeed 263 for their unfortunate burnout which was later corrected.

That's why I cannot stress it enough that when your regional is well run and is being widely talked about you really need to thank those involved =), Teams for their continued understanding and cooperation, Volunteers and Coordinators who keep the regional going on time and flawless =). I don't think I've seen any other regional work harder to ensure and achieve the multiple goals set forth other then the Championship itself.

[mtaman02]

Originally Posted by Mark McLeod

We used the Chesapeake field on Long Island after you were done with it. Now it's on it's way to Atlanta.

Actually its on its / should be in Michigan AND THEN it goes to Atlanta =P

Some place out in Yipslanti =)

I should know I put it on the truck =P (boy did Bill have it easy that regional =P)

[AlexD744]

Isreal and Waterloo are both small events and might not have as many matchs (I'm not sure about this). If they were less matches wouldn't that mean that a few matches could sway the percentage a lot. Isn't a rule of statistics that the more you flip a coin the evener it will get. Well maybe those fields weren't "flipped" as much and it show in the win percentage. i will check on how many matches were played.