Troubleshooting: Some AprilTags Unavailable for Targeting and Registration
To register scans with AprilTags in Dot3D, you must ensure that there are at least three unique AprilTags selected for targeting. This will typically take place automatically as shown here, however you sometimes may need to readjust the active tags in each frame if you have multiple tags in the same key frames (multiple tags in view of the scanner at the same time during scanning).
It is recommended that you spread out your AprilTags so that each one can be captured in a separate key frame. This will likely avoid any of the issues noted below, and will also result in a tighter registration between the data sets.
It is recommended that you spread out your AprilTags so that each one can be captured in a separate key frame. This will likely avoid any of the issues noted below, and will also result in a tighter registration between the data sets.
Otherwise, if Dot3D is failing to recognize all your AprilTags as available for targeting, please be advised of the following:
- If there are several tags detected in a single key frame, the system automatically selects the one as active that is most centered in the image.
- This may result in some AprilTags being unavailable for targeting if not automatically selected as the active target in any key frames.
- In this case, the user can correct this with the "View / Change Associations" option. To do this, you will need to open the relevant key frame, then click/tap on a green AprilTag and "Set As Main":
Open a key frame from this dialog (note that all the main (circled) Tags are the same (Tag ID 2)):
Click on a green AT and "Set as Main"
AT becomes circled as a consequence:
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