ARENA Fault

[Jimmy Cao]

I understand your frustration with regards to robot(s) losing communication with FMS during matches, but you need to understand a few things.

1) Sometimes, it is genuinely the fault of the robot (or team that fielded the robot). Robots can lose communication with FMS for a variety of reasons, a large number of which result from how the team hooked up their robot. A bad ribbon cable, poor electrical connection, etc. could all cause this. FMS logs will just show a large number (100%) dropped packets for the duration of such events. However, a large number of other events can cause FMS to show 100% dropped packets, hence it is (near) impossible to arrive at a sound conclusion. As much as any of us who've been hit by comm issues doesn't want to admit it, it is very like that the fault isn't in FMS, but its in some aspect of our robot. In the rare situations where FMS did fail, I wholeheartedly trust the people behind the scoring table to diagnose the issue accordingly and act appropriately, but I'm also willing to accept that they can't possibly figure everything out. Remember, our control system consists of a ultraportable PC, a wireless gaming adapter, and an industrial grade controller. Were any 2 of those components really intended to work in unison? No. This leaves plenty of room for small mistakes to cause catastrophic results (consider all the possible issues with the radio's reset button, a plug for the radio that's probably not designed to be shaken as robots collide/cross bumps/etc, and all other potential failure points, these wouldn't be on a system who's sole purpose was to robustly control FRC Robots. They also would probably make the system cost prohibitive).

2) The field crew does its very best to give every team the chance to play; regardless of whether their comm issues are robot-sided or field-sided. Genuine mistakes happen, and the FTA and co. would never intentionally ignore situations in which it is clear that a FMS bug caused robot(s) to lose communication. However, I have yet to see a situation in which FMS causes less than all of the robots on the field to lose communication.

3) The FTAs do their best to diagnose the issue, but understand that they're people too. I know first-hand that the FTA for the TC and Detroit FiM District events will stop at nothing to pinpoint the cause of robots not communicating with the field right. The FTA at Cass Tech was also obviously working extremely hard, as the back of his shirt was clearly covered in sweat. Unfortunately, there were still robots that had comm issues at both events. Nevertheless, it is important to credit the hard work that the FTAs (and FTAAs) do at all the events, since they're the ones working (largely) behind the scenes to make the whole event run smoothly.

4) All that being said, it is crucial that each and every team take all necessary measures to ensure that their robot doesn't become the cause of comm issues. Ensure that all electrical connections (especially those to the radio, cRIO, etc) are secure, especially if you traverse bumps. Ensure your code is robust, as a watchdog bug can (and will) cause a loss of comm, either momentarily or permanently.

5) Remember that FRC competitions are volunteer run. The FTAs are volunteers, the refs are volunteers, the querers are volunteers. If you know a cRIO/controls/something expert who's willing to volunteer at the events to look at robots who've had communication issues, then invite them to offer their help. Otherwise, other teams are more than willing to provide any assistance they can. If you're continuously having comm problems, ask the FTA if you can try to sync to the field after the end of matches on Friday (or maybe even at lunch).

I guess that's all I have to contribute...