We are using photonvision on a raspberry pi 3 b+. What is the best way to stream the camera to the drivers? We have tried opening the stream in a web browser and have also tried it on shuffleboard and both seem to freeze up at competitions but work fine tethered in the pits or at our shop. We aren’t using any code to set up a camera server. Should we be?
What bit rate are you using at the shop?
Also recommend a second screen placed up higher for the drivers to look at.
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We do have a second screen that isn’t what I meant though. I lowered the stream to nearly the lowest and it still freezes up and is unusable during matches. We actual unplugged the PI and stopped trying to use since it never worked during a match.
By lowest do you mean both resolution and frame rate? Also by freeze up, do you mean lots of buffing/freeze but a few frames get through now and then or do you just not get an image or just one image?
Resolution is set to 640 x 480 and stream is 320 x 240 I think. We may have tried even lower for the stream. Also when I say freezing sometimes it just lags bad other times it is just one image the entire match
I’d have to check frame rate tonight at the shop.
Where do we set bit rate? I see Resolution and Frame Rate. I think we were running at 640 x 480 30 fps. and the stream was at 320 x 180.
Looking back thru the driverstation logs we had a ton of dropped packets and latency while trying to use photonvision at the competition. When we unhooked the pi from the network switch that completely went away.
Did you measure the bandwidth your robot was using? Measuring Bandwidth Usage — FIRST Robotics Competition documentation
We have not. But now that you have pointed this out it is the first thing I am doing in the morning.
Other than the camera system what could be using band width to cause an issue?
We don’t have any other sensors on our robot other that the encoders for the neo’s and falcons.
We’re using mk4i swerve with falcons and cancoders for the drive system.
The manipulator has 3 neos and one falcon.
And LEDS via a blinkin plugged into a PWM port.
That’s all we have. Soft limits and Pid/set points for holding the manipulator system where we want it for pick and placing game pieces.
I’ve seen some teams say they are using multiple cameras with little to no issue. We can’t seem to get one working. This was problem last year as well.
