Controller/Cortex Connection Issue

Hey everyone! I know this issue is very prevalent among the cortex based system but we just had a competition yesterday and our controllers keep cutting out every 20 seconds (they come back after 3-5 seconds). The main controller flashes red sometimes (which obviously signals loss of connection) but also the controllers seem to be perfectly fine yet not controlling the robot. We had to completely replace the cortex and the controllers but we still don’t know what the issue may be. If you all have any suggestions that would be greatly appreciated.
Solutions tried:
Keys securely connected to both cortex and controllers (so they don’t fall out)
Fresh Robot and Controller Battery Replacements (We don’t have a backup battery though)
Cortex/Controller Replacement

A picture of the robot? I’ve seen people put their radios in the middle of a mass of metal before. It turns out radios don’t work very well in a Faraday cage. If your radio is deep in your robot with lots of metal around it, try moving it out with a short USB extender.

I’m on Raghib’s team, and our robot has the cortex so one side (the one with the key) is facing the outside of the robot, with no metal obstructing it. Our cortex last year was in the center of our DR4B (we had metal all around it), and we had no problems. I don’t have any pictures on me right now, but I can try to get some soon.

Yeah I got a few pictures IMG_0518[1].JPG

We also have a power expander on our robot too.

Doesn’t look like you have a backup battery. It’ll help with this.

The root cause of this issue for me was that the battery would disconnect. A solution I’ve seen (but haven’t tried) is literally jamming something next to the battery connection to keep constant contact.

Alright thanks man for the solution we’ll try that! Also what do you suggest to “jam” the battery in?

My team uses a single link of chain that’s cut in half and we just shove the little piece that connects the links together in next to a battery extension

I’ve heard this. I’ve also heard of a 393 motor screw, but I’m more scared to try it. Pretty much anything Vex legal that’ll seem to work will probably be fine.

@Got a Screw Loose
If you aren’t using a vex 393 motor screw that what holding your motors on? That is the required screw to hold edr motors on. What are you doing?

Lol, miscommunication. We’re talking about bracing the battery to ensure a consistent connection. And zip ties and duct tape are always good answers.