Re: elim field issue?
 

Just got back from Championships. Had a GREAT time! Was a huge bummer to lose the rubber match and not have 3 on 3. That's the only way I want to win or to lose - with everyone at full strength!

Here's what happened...

1) Never lost comm the whole event.
2) First playoff match our alliance captain was in the Red 1 station and had intermittent comm during their match. Cost us the match 12 to 9.
2) Second playoff match everyone ran and we won it 12 to 8 I think.
3) Third playoff match we're in Red 1.
- Robot works fine in systems check right before putting it on the field (with a tether of course).
- We power up on the field, go to the driver station, everyone gets comm but our station (R1).
- I run out onto the field and the FTA joins me. We look at the radio and it has Power and Ethernet but no Data/Activity.
- He says to recycle the radio or robot. I ask which he wants and he says do the whole robot. I do so and walk back to the Driver Station.
- Everything comes up fine. We run auton, never "hit" anything or any bumps or anything but notice it ends it's auton run by just "coasting" to a stop (not normal). We look down and see no comm!
- FTA runs over to our station and resets something but it doesn't come back.
- After the match we all look and again, Power, Ethernet, no Data Activity to the field radio.
- FTA says he's seen a lot of radios just crapping out and maybe that happened to ours even though it comes back the next time. No recourse, we're done for the championships. Blech. :P

I'm going to run that same radio (we have two) back at the school for a few weeks and see if it ever loses comm again. We'll run it literally for dozens of hours and if it never loses comm again, I have to believe it's a flakey field issue. If it fails, then I'll swap in the backup radio and see how that goes.

BTW, our entire electrical system is on thick lexan, nothing is grounded to the frame, everything is shielded, zip tied and super clean. I really, really doubt it's a wiring fault. We did check multiple times as part of our pre-inspection checklist for all 4 events we've been to including Championship and nothing is connected to ground. Also, our power cable to our radio is very securely taped to the radio. You can not possibly remove it without taking a 2" wide piece of tape wrapped around it from the top to the bottom of the radio. It cannot shake or jiggle loose. Same for the ethernet.

If you all have any suggestions for other diags to do, we'll give them a run when we get it back in a couple weeks. Would be great to track this down as it cost us huge.

Thanks!
John

Re: elim field issue?
 

Same here but in Grand Valley. Our auto worked fine then boom nothing. We were in the same spot middle red each time. We asked to speak with the FTA and they refused. The head ref did come speak to us and say it wasn't a field issue. Which we didn't understand because we worked just fine in the other 5 spots. Makes no sense to me. We wanted to replace the router but there weren't any left. Anybody know where we can get a new 1? Can I go to someplace like Best Buy and purchase 1?

Re: elim field issue?
 

There is at lest one other scenario which creates the symptoms you describe. I saw it happen multiple times at NC, where a team's autonomous worked but then had no control in tel-op. When the NI rep looked at it, he found they had an infinite loop in their autonomous code. Since it never completed, it never transitioned to tele-op. One time when they were on the field, this happened again. The during the match they got bumped and the cRio rebooted. When it came back up, it recognized that it should be in tele-op and they were able to begin driving. This can be a coding issue. There are threads both here and at NI.com/first about it.

Testing autonomous and tele-op via tether by seeing if you can run each is not the same as having one run after the other automatically. I'm told that there si a capability on the classmate to run a simulated match which might find such a problem. Another possibility is to download FMS lite and to run your own simulated match using (most of) the same software running on the FIRST fields.

Re: elim field issue?
 

Actually, I beleive Andy from 233, 254's alliance member, told me that they had replaced their radio, still had the problems and then were in the process of replacing their cRio. And I bleive that they didn't have any problems after that. I also beleive 51, our opponent on Galileo, also replaced their cRio and at least for the match we played them in they were fine. Our team was also losing and regaining comms, and after we got out, we were told that it was most likely our cRio. I beleive it could be the ethernet jack in the cRio gets worn, between tethering and coding and eveything.

Re: elim field issue?
 

Correct. According to the FTA, it appeared that the cRio had "stopped running the program" mid-match, so we borrowed 971's cRio and had no further problems.

Re: elim field issue?
 

Ah, nice. I'm starting to think 2854 was having the same issue with a bad cRIO. Especially since we took it off of our robot last year as well.

Re: elim field issue?
 

We run a short 2 foot ethernet wire from our cRio to a female-to-female jack which is mounted to our frame. That way when we plug/unplug in our tether all the time, and also if our bot goes crazy and jerks on the wire, it will only ruin a $3 jack instead of our $1,500 cRio. It works really well. I checked that jack and it is fine. Remember, I had Power and Ethernet lights on the radio both times when I had no data/activity. If the ethernet cable/jack was bad, that light should be out. It certainly goes out when I unplug the wire. Plus, wiggling it as much and hard as you want causes no interruption in the signal/light.

When you all say you replaced the cRio, did you send it in for repair and get a new one or what? What did that cost?

Also, we do have a backup radio and a backup cRio. I'm anxious to get our bot back and start running it back here at the school. If it dies again, then I'll switch each component out one at a time and try and get it to happen again. That might give me a clue.

Finally, I received a PM from someone who said that they don't use Lexan to mount the cRio because it can cause static buildup. They saw that last year. Well, last year was nuts with that Regolith floor. How many of you mount yours on Lexan, and have you ever seen it where someone walked up to the system and touched it and caused it to lockup from a static shock?

Thanks all for your help. I miss the days of the IFI systems that booted in 2 seconds and just ran and ran forever without ever lockup up. Ah well, there's progress for you... :P

Re: elim field issue?
 

For what it's worth, in the Curie QF? match that was replayed for a field fault (ball stuck in return), 1676 was in Red 1 and had Auton but no teleop. Removing and reinserting the USB devices caused some to become active, but the joysticks were still not visible to the classmate. This was repeated several times with same results.