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JeVois Frequently Freezing

0 votes

I just got my JeVois and am running into a problem.  I flashed the SD card with the latest image (SD card came with the beginner kit) and plugged the USB cable (also supplied with the beginner kit) into a USB 3.0 port on a MacBook Pro.

When I run the TensorFlowSingle (464x240) in either JeVois Inventor or Webcamoid it will work for anywhere from 10s to 1m, then freeze.

If using Inventor, that's it -- I need to unplug/plug the device to get it back.  If using Webcamoid, I have to stop/start the camera a few times to get it back.

I'm just using out of the box demos per instruction with all JeVois parts...so I don't think I'm doing anything wrong.

I can't imagine this is normal.  It seems like a cool device, but if it freezes so frequently, I can't use it in my device.  Any suggestions?


asked Jan 10, 2020 in Hardware Questions by nickbild (120 points)

1 Answer

0 votes
Usually, this could be either a problem with the USB cable, or with the connectors. The mini-USB connector on the camera is not designed to handle mechanical stress. If you are moving the camera around to look at various objects, it can sometimes disconnect (even though the connector is still plugged in, the connection gets temporarily broken). Usually when we give demos where the camera moves a lot, we mount it on a tripod and we secure the USB cable to one leg of the tripod so that it will not move at all at the connector when the tripod is moved. Some First Robotics teams have designed mounts with strain relief. Look for 'jevois' at thingiverse.com, for example this one:


which also has a mount for a ring of LEDs (for night/IR vision).

If the problem occurs when the camera is not moving at all, then the next likely cause is a bad USB cable. We have had a few reports of bad cables. We have changed cable brand since then but maybe try another cable if you have one around.
answered Jan 28, 2020 by JeVois (46,580 points)
In my case it was the power.  A single USB 3.0 port wasn't sufficient under heavy load.  Plugging into 2 USB 3.0 ports keeps it running.
Thanks for letting us know! Usually USB 3.0 ports are no problem (They are supposed to be able to source 5V @ 0.9A = 4.5 Watts and JeVois uses less than 3 Watts). Good to know for the future.