Top Ten Reasons Robot Loses Com in a collision ?

[de_]

Just wondering if anyone can contribution ideas as to possible causes to our robot occasionally losing com in collisions on the field. At this point of time I am not aware that the CRio had rebooted as a result but will try to confirm.

This is what we have looked at.
Bridge power jack contact looks solid. (will hot glue it in anyway)
Good soldered connections from bridge to converter
Converter to 12v plug in power distribution board looks solid
Crio power power plug, Crio power plug in power distribution board.
Network cable contacts at Crio and bridge ? Any risks there ?
Terminal lugs in main power distribution board possibly coming loose (main circuit breaker lugs, power distribution lugs)
Loosening contacts on battery terminals

Any other suggestions or recommended good practises that may not be obvious ?

Anyone know how good the regulation is for the 12 and 24 volt outputs on the pdb ? How low can the battery go before the CRio or Bridge is at risk ?

[Vikesrock]

Check for ground shorted to the robot frame. The cRIO and camera are both chassis grounded and must be isolated from the robot frame. Also, if you are using any of the RS-775 motors make sure they don't have a lead shorted to the case.

[Colin P]

Anderson cables disconnecting even momentarily will reboot the robot.
cRIO power cables coming undone
Radio power cable getting knocked out from the radio. We lost com twice at an event, taped the radio power cable in, and were fine the rest of the event.

Zip-tie your anderson connectors together, check you cRIO power, and tape down your radio power cable. These are the three problems we had and our three solutions.

[Alan Anderson]

For how long do you lose communication? 20-30 seconds is a cRIO reboot. 45-60 seconds is a DAP reboot. 1-2 seconds might perhaps be a network cable issue.

The 12v and 24v boosted supplies out of the PDB are good down to less than five volts input from the battery.

[davidthefat]

I would say make a big PCB board instead of having tons of wires. If you can't don't use connectors, solder them.

[nuggetsyl]

Reason number 1
Because its not an IFI controller.

[Danny Diaz]

Originally Posted by nuggetsyl

Reason number 1
Because its not an IFI controller.

No, reason #1 is:

"Because it's not CHUCK NORRIS!"

-Danny

[crake]

Originally Posted by Danny Diaz

No, reason #1 is:
"Because it's not CHUCK NORRIS!"

THAT'S IT! I knew there was a feature missing.

In all seriousness - lots of good tips in the thread. Definately make sure you're connected to the correct PD outputs as well. Though as pointed out, if you get a reset, it would be longer than a few seconds.

[de_]

Originally Posted by Alan Anderson

For how long do you lose communication? 20-30 seconds is a cRIO reboot. 45-60 seconds is a DAP reboot. 1-2 seconds might perhaps be a network cable issue.

The 12v and 24v boosted supplies out of the PDB are good down to less than five volts input from the battery.

More than 1-2 seconds. Will watch closely at regional next weekend.

[Al Skierkiewicz]

Crio is disabled when battery falls below 5.5 volts. 24 volt, 12 volt and 5 volt power supplies fail at about 4.5 volts at the battery input to the PD.

[Tom Line]

I haven't seen anyone mention the reset button on the router. The old one was a spring-retained button and could be triggered by slamming down on the bump last year. We hot glued that one too.

[LightWaves1636]

We lost comms because our battery slipped out and knocked into our PDB connections. So

A: Secure the battery really well and
B: Protect your electronics in a well ventilated area

[bladetech932]

The number one problem at the regionals that I have been to has been the Ethernet cable between the bridge and the c-rio after collisions teams would lose comms so make sure the connections are secured