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nuggetsyl
05-03-2016, 17:19
We keep losing coms each match when the robot hits a bump. We are not losing power to the robot. It reloads and then reloads code. If you have and suggestions we are all ears.

rtfgnow
05-03-2016, 17:22
My first recommendation is to talk to the CSA or FTA at your event. They have more tools available to diagnose the issue.

Why do you think you are not losing power if your code has to reload? How long is the link down for?

Make sure to double check all wires to the roboRIO and radio and that they are seated correctly. Check the red and yellow fuses on your PDP too. You should be pushing them in until your finger hurts, then push more.

cad321
05-03-2016, 17:43
Ensure that your power cables to the roborio are securely fastened and not in the slightest bit loose. Earlier in the season we had the same issue and were convinced it wasn't the roborio loosing power because we would watch it and the lights never seemed to go out.

It ended up being that the roborio lost power for a 1/10th of a second and then booted back up making the lights appear to always be on. Once we reseated the roborio cables and ensured they were tight, the problem went away.

engunneer
05-03-2016, 18:00
Percussive troubleshooting is in order. For our 2014 bot, we found the bad connection by tapping the back of the electronics board in different spots with a mallet. As you tap around, watch for the problem. When you get it narrowed down to a repeatable spot, you know where to look.

If it doesn't happen with this method, tap harder.

nuggetsyl
05-03-2016, 18:58
Ensure that your power cables to the roborio are securely fastened and not in the slightest bit loose. Earlier in the season we had the same issue and were convinced it wasn't the roborio loosing power because we would watch it and the lights never seemed to go out.

It ended up being that the roborio lost power for a 1/10th of a second and then booted back up making the lights appear to always be on. Once we reseated the roborio cables and ensured they were tight, the problem went away.


I owe you a beer or rootbeer depending on how old you are thanks.

Conor Ryan
05-03-2016, 19:31
Tug Test all wires!

mwtidd
06-03-2016, 07:50
We saw a similar thing, and found that it was with the connection between the radio's power cord and the voltage regulator. If this connection wiggles at all the radio dies. Once you have it snuggly connected (and pull tested). You may want to consider hot gluing the connections to the regulator.

JohnSchneider
06-03-2016, 13:21
You may want to consider hot gluing the connections to the regulator.

Isn't this a pretty controversial interpretation of "not modifying electrical components"? I know we've been called and had to remove hot glue before... is there something I missed?

jajabinx124
06-03-2016, 13:30
So during bag and tag night for Team 2052 KnightKrawler whenever we went under the low bar, the top of our robot hits the bar sometimes and that caused us to lose comms. We think the shock affected the radio and we put some foam like material to absorb the shock near our d-link so we wouldn't lose comms and at lake superior we never had that issue.

Joe Ross
06-03-2016, 13:39
Isn't this a pretty controversial interpretation of "not modifying electrical components"? I know we've been called and had to remove hot glue before... is there something I missed?

Compare the 2014 R64 to the 2016 R66

The Driver Station software, cRIO, Power Distribution Board, Digital Sidecars, Analog Breakouts, Solenoid Breakouts,
RSL, 120A breaker, motor controllers, relay modules, Wireless Bridge, 12VDC-5VDC converter, and batteries shall not
be tampered with, modified, or adjusted in any way (tampering includes drilling, cutting, machining, gluing, rewiring,
disassembling, etc.), with the following exceptions:

The Driver Station software, roboRIO, Power Distribution Panel, Pneumatics Control Modules,
Voltage Regulator Modules, RSL, 120A breaker, motor controllers, relay modules, Wireless Bridge,
and batteries shall not be tampered with, modified, or adjusted in any way (tampering includes
drilling, cutting, machining, rewiring, disassembling, etc.), with the following exceptions:

DonRotolo
06-03-2016, 22:09
Compare the 2014 R64 to the 2016 R66
Wait a minute: Do you mean that the rules change from year to year? When did that start happening? :rolleyes:

JohnSchneider
06-03-2016, 22:55
Wait a minute: Do you mean that the rules change from year to year? When did that start happening? :rolleyes:

Its not really a change. 2016 just doesn't mention gluing specifically but is arguably still included in the "etc." at the end of the rule. So while yes the words of the rule are different, the intent is possibly the same and is therefore controversial.

cgmv123
06-03-2016, 23:07
Its not really a change. 2016 just doesn't mention gluing specifically but is arguably still included in the "etc." at the end of the rule. So while yes the words of the rule are different, the intent is possibly the same and is therefore controversial.

2016 R66-F says adhesives are allowed to secure cables. That was not allowed by the 2014 version of the rule.

Boltman
06-03-2016, 23:12
Good! Since we went dead qual 1 and quickly secured the connections..with adhesives. Worked rest of the way.