Losing connection when ramping over defenses

[Landonh12]

Has anyone else experienced this? I have checked and made sure that all of the wiring is good on our robot, yet every time we ramp over a defense (i.e. rock wall) and slam down, our robot drops connection. All wires are secured and locked in to their ports (power, ethernet, pwm, etc.)

Could this be a result of shock causing the radio/roboRIO to reboot?

If you have had this problem, please share your solutions.

[Jon Stratis]

Check your main breaker to make sure it isn't bad. There are a couple each year... With the bad ones, you can tell by lightly tapping on the red button while watching the LED's on the robot - with a bad one they'll flicker.

My team's main breaker was bad, but in a different way- the lever inside that lets you turn it on was broken. Brand new, out of the box for may be a day. It was the only one I've seen broken like that. Fortunately, we had a few spares sitting around

[GeeTwo]

We had this happen to us a few times Saturday during our first test drives over the defenses. We are going to do trouble-shooting this evening. I also saw another thread that described a similar (possibly the same) problem.

[evanperryg]

Originally Posted by Jon Stratis

My team's main breaker was bad, but in a different way- the lever inside that lets you turn it on was broken. Brand new, out of the box for may be a day. It was the only one I've seen broken like that. Fortunately, we had a few spares sitting around

We had the same issue a couple years ago, had to mash the lever or a little bit of vibration would cut power to the bot. OP, if it isn't your breaker, check to see if the power cable for your router is firmly attached. We found that those hard impacts can cause it to get loose unless securely mounted. If it's available to you, I strongly suggest a 3D printed holder for the plug to keep it well secured.

[Christopher149]

We have been having this issue, and I think ours came from the voltage supply blacking out. We plan to modify our drive train so that hopefully it won't recur.

[Al Skierkiewicz]

Double check that the fuses on the PDP are full inserted. They can look good but are actually far from fully mating. Are you getting just a very short (one or two seconds) drop or are you getting a radio reboot?

[Landonh12]

Originally Posted by Al Skierkiewicz

Double check that the fuses on the PDP are full inserted. They can look good but are actually far from fully mating. Are you getting just a very short (one or two seconds) drop or are you getting a radio reboot?

It seems like a radio reboot, I'm just speaking from what the students have told me. It goes down for a good 30 secs.

I'll check the main breaker as well. Thanks guys.

[Joe Ross]

What do you learn from the driver station logs? http://wpilib.screenstepslive.com/s/...og-file-viewer

[cad321]

We have been experiencing this exact same issue. When we go over the defences we drop connection. We have isolated the issue to the roborio. We're still trying to figure out how to fix it. We're currently trying to add suspension to our roborio and hoping that fixes it.

[rich2202]

What power plug in to the radio are you using? Wiggle it. If you do not get stable power, that might be your problem.

[catacon]

We had this happen last night too. The power connector for the radio came unplugged while going over the rock wall.

[Landonh12]

Originally Posted by Joe Ross

What do you learn from the driver station logs? http://wpilib.screenstepslive.com/s/...og-file-viewer

I haven't personally seen any of the logs, but I can check when I get to the meeting this afternoon. Usually there aren't any errors from what I've seen, but I could be wrong.

[Procolsaurus]

Originally Posted by Al Skierkiewicz

Double check that the fuses on the PDP are full inserted.

We had very similar comms issues, which were solved by checking the fuses.

[Alan Anderson]

Originally Posted by Al Skierkiewicz

Double check that the fuses on the PDP are full inserted.

Those minifuses are very good at pretending to be fully seated when they really aren't. My advice to teams for getting them in all the way:

• Push them in all the way.
• Let go and notice how they look like they're in all the way.
• Push harder. Literally until it hurts.
• Notice that they go in a lot more.

As a rule of thumb (!), if you can pull them out with your fingers they aren't pushed in hard enough.

[roystur44]

If your using a two speed transmission check to make sure your in low.