USB Cameras Going Rogue

[flynn248]

Background Info

Currently the PID's of each device is saved in a file in the logs/ directory. This is then read by stop_data_collection.sh to kill these devices.

Description

For some reason the PID saved in the file for one of the USB cameras does not correlate to the PID outputted by
$ sudo fuser /dev/video{port}
This results in the camera not being killed successfully. Then when the devices are started up again, the ROS script that runs the camera fails because it cannot open another stream for that camera since it still exists.

Currently each script's output is sent to the logs/ directory and not to the terminal. There are currently no automatic checks to see if a device truly booted up successfully.

Possible Solutions

1. Develop a more robust system that will inform the user right away if a device did not boot up successfully. Should be done anyways.
2. When stopping the devices, add extra checks for the USB cameras to see if they were successfully killed. If not, then forcefully kill them using
   $ sudo fuser /dev/video{port}

[flynn248]

Currently implemented solution 2. Added an extra check to see if the USB camera did in fact get killed in stop_data_collection.sh.

This has not been tested fully. But on some quick tests, it should be functioning properly.

Solution 1 should also be worked on, but may be put into a separate issue.