Robot light going red or orange when it hits a platform

Our team is still using cortex on the robot, but when we try to get on to the platform, the robot light on the cortex goes orange or red. Generally speaking, it doesn’t affect the robot, but sometimes the movement control will start to jitter until you power cycle it. We have replaced the battery and cortex and also have switched the movement motors to seperate circuits (i.e. right motors on first 5 ports and left motors on last 5 ports). Any help would be appreciated.

V5 or cortex?

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Our team is currently using cortex.

which light? battery or vexnet?

The battery light on the cortex

then maybe your cortex’s battery port is loose or wonky in some way. but then you say you’ve tried replacing it. I can’t think what else it could be tho, try recreating the event by shaking the robot or something. or wiggling the battery cord.

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This is probably right. Are you using a backup battery also?

Unplug that, and jitter around the battery cable connection to the cortex. If your joystick loses connection briefly, then it’s probably that the connection is loose.
I’ve heard of teams who used a broken chain link to shove next to the loose battery connector to force it to stay in contact with the Cortex. I used to have the same issue myself, but it was fine again when I plugged in the backup battery.

Amusing Anecdote

I forgot to plug that backup battery in for one match, and I got hit and died. Thankfully, it was a lucky pairing and the match was still won. It was embarrassing to be dead in the water, though.

What is probably happening is that when your motors hit the platform, they are consuming a lot of power, which triggers the low voltage warning you are seeing. How many motors do you have on your drive? If it doesn’t disconnect, I don’t think there is much to worry about. Are you using a power expander?

Unfortunately, we somehow lost our only power expander and are currently using 4 motors on our drive.

Back when we used cortex loose battery ports were a fairly common problem. A team in our area recommended that we use the battery extension cable because they tend to hold the battery a bit tighter and can be replaced more easily than a cortex if the port does get messed up. We took their advice and it almost completely eliminated the problem.