MartyG-RealSense
commented
4 years ago Hi @azalac In situations where the camera can no longer be detected and hardware_reset() does not solve the problem, some RealSense users have solved the problem by resetting the entire USB port with an Ubuntu script instead of just resetting the camera. I recommend googling for ubuntu usb reset script for research leads.
The link below has an example of a USB port reset project that a RealSense user developed.
https://github.com/IntelRealSense/librealsense/issues/2161#issuecomment-587457793
Another RealSense user with camera enumeration problems greatly improved reliability by using industrial grade USB cables.
https://github.com/IntelRealSense/librealsense/issues/2741#issuecomment-548914984
If a program uses set_real_time in the False state then it may also be more prone to issues when stopping the pipeline, whereas such errors are less likely to occur if set_real_time is set to True. Here is an example:
azalac
Issue Description
I have a python script that I'm using to process the output of the camera. Since this script is still in development, it occasionally hard crashes (seg faults, when I sigkill it due to freezes, etc). After doing this a few times (3-4), my D415 stops connecting to my PC entirely, forcing me to reboot to fix it. I've previously used a D435, and I still had the issue. Unfortunately, I don't have access to the D435 anymore, so I won't be able to use it.
I've tried unplugging the camera, and plugging it back in, but that doesn't fix anything. I can't send a hardware reset to the camera, since it's not even detected in lsusb.
I don't believe this is a power issue. I can run the script for many hours without issue. The only time this occurs is after my script crashes, and the pipelines don't get closed properly.
Looking at dmesg, it seems like there's a driver issue. I've tried reloading the uvcvideo kernel module, but it didn't have any effect. I've also tried to disable and re-enable the entire hub, but it only caused the hub to stop working properly.
Here's the relevant parts from dmesg:
I'm not sure if the 'Failed to query' errors are normal - I get many of them even when the camera's working properly.
During this specific issue, I didn't re-plug the camera before reloading the uvcvideo module, but I've done it in the past and it's had no effect. After re-plugging it, I just get lots of 'new device / device read error' messages in dmesg before I finally get an 'unable to enumerate' error.
I've had this issue countless times (at least 10 times by now), so I've looked at a lot of usb related realsense issues but I haven't found any that are similar to my issue. Any help would be greatly appreciated.