Ar tag detection manual 484

[MewtR]

Assignee Section

Description

Essentially same as #482 with some minor improvements. If this is approved we can actually skip merging #482 and just merge this one instead because it has all the same commits.

Main points:

• The AR stream is only started when a request is made to start it (by clicking on the AR button)
• Clicking the AR button while AR detection is on will only kill the nodes if no one else is currently using it.

Steps for Testing

Prerequisites (from #482)

• Make sure you install ar_track_alvar: sudo apt install ros-melodic-ar-track-alvar
• Calibrate your camera by following the instructions here
• Print out some AR tags. They can be found here for example.

I won't include the steps for testing the actual AR detection (making the red square turn green). Refer to #482 for how to do that.

1. Start the project as usual
2. Start a video stream as usual and click on the AR button to get the red square (it takes a few seconds).
3. At this point you should see /ar_track_alvar_X as well as /ar_tracker_X in the output of rosnode list. (X being video0Cam or whatever the topic is called)
4. Click the AR button again and wait for it to shut down. Go back to the terminal and make sure the AR nodes are no longer in the output of rosnode list
5. Click the AR button again to turn it back on.
6. Open the project in a new tab and get an AR stream going there as well.
7. Clicking the AR button in the first tab tab shouldn't kill the AR nodes but the red square should still disappear.
8. At this point you can play around with turning them on/off in either tab. As long as one of them remains on the AR should nodes should remain alive.
9. Turn off the AR streams in both tabs and watch the AR nodes die again.

closes #484

The approval from all software team leads is necessary before merging.

Reviewer Section

Aside from local testing and the General Integration Test it is implied that static analysis should be included in the verification process.

• [x] Local Test Performed Successfully
• [ ] General Integration Test Performed Successfully

For Pull Requests that do not include code changes, it is not required to perform the tests above.

[MewtR]

Refer to #482 for beginning of the discussion.

[domludera]

Tested the steps locally, and it works as specified

[PeterGhimself]

Same as @domludera, just tested and it works fine on my end