Re: Wrong Field Measurements and Bad FMS
 

Team 1977 was wondering about the FMS too....By our count, somewhere between 10 and 20 teams had issues during matches. Some of that is likely coincidence, but there was way too much interference to mark it all as something from a team. Our robot worked perfectly on the practice matches and in the pit while tethered, but for the first day of qualifiers, we could do nothing. No autonomous, no teleop, nothing. As soon as we put it on the field, we went dead, with no robots hitting us or interference. When we brought it back to the pit, it worked perfectly every time. We had several officials look it over and find no explanation. We also had several people check over the code and find no explanation. We finally made it work, albeit with lag, by disabling the autonomous feature and switching out the CRIO. However, other teams that had communication issues had been cleared up on their own, leading to the possibility that making these changes was coincidence. Our robot was the worst off, losing a full day of competition, but another team was only able to run for half of every match before losing connection. Several times, a team would be dead at the start of a match and gain connection about 10 seconds into teleop mode. Rebooting the CRIO helped for a time, but it takes a lot of time within each match and only seems to be a temporary fix. It seems too big of a deal involving too many teams to be marked down as an error on every team. (Unsure, but it may have happened to a team in the finals as well. Last 10 seconds they were not moving, but it could have been driver error.)

Re: Wrong Field Measurements and Bad FMS
 

The overall dimension of the field is specced as +4.0/-0in. and the tape is specced to trisect this area. This means that +1.33in. should be the tolerance for the size of each zone. Additionally the field and carpet stretching as mentioned by other posters above may cause additional deviation from this measurement that is very difficult for FIRST/event staff to do anything about.

If 1 inch honestly effects your autonomous:
1. You have a pretty solid PID running, it should be trivial for your team to tweak the value to fix your auto
2. It is unlikely your robot will score many goals in teleop this season unless you are using automatic positioning. A driver cannot achieve inch accurate positioning from 30+ feet away. Even with auto positioning any defense at all will cause a deviation of substantially more than an inch.

Re: Wrong Field Measurements and Bad FMS
 

We can and should expect tape to be placed in the right spot. Unfortunately I think that part of this thread got lost amongst the unfounded FMS complaints.

It also wasn't clear whether the tape was incorrectly placed from the start, or whether the tape was placed correctly then appeared to be incorrect after a weekend full of matches.

This is an easy problem to deal with appropriately. As per section 5.5.7 of the manual, the field will be open for measurements for one hour at some point prior to practice matches starting. Go out on the field, take a look at the small details that you know will affect your robot, and point out any errors that are outside the tolerances to the Field Supervisor and/or FTA.