Apriltag relocalization not relocalizing?

[Kessie]

Hi,
We have enabled en_tag_fixed_frame in voxl-vision-hub to use apriltag detection as a way to relocalize indoor.
Am i correct to assume that the following is a tag located on the ground at point 0,0,0?
"T_tag_wrt_fixed": [0, 0, 0],
"R_tag_to_fixed": [[0, -1, 0], [1, 0, 0], [0, 0, 1]]

What would be the rotation matrix for a tag located forward against the wall?
What's the best way to test that the relocalisation actually happens?

---

system-image: 1.7.10-M0054-14.1a-perf
kernel: #1 SMP PREEMPT Fri Sep 27 21:59:02 UTC 2024 4.19.125

hw platform: M0054
mach.var: 1.0.1

voxl-suite: 1.3.5

[James Strawson]

yes, that's the correct rotation matrix for a tag on the ground.

For a tag on the wall with a center 1m off the ground you can use:
"T_tag_wrt_fixed": [0, 0, -1],
"R_tag_to_fixed": [[0, 0, 1], [1, 0, 0], [0, 1, 0]]

The second video of this docs page walks you through the voxl-vision-hub command line args to help you debug relocalization.