Apriltag and accurate rotation measurement

Apriltag tag25_09 is used for rotation measurement. I have tag size constraint. Can’t use tag size bigger than 6cm.
So rotation angles are quite fluctuate and noisy.
How can I improve the rotation angle accuracy in such situation?

You should filter the rotation angle input. After detecting a tag once you should be able to track it and filter the rotation angle by expecting movement to follow a certain profile.

Also, increase the camera exposure and decrease AGC, this makes the image more stable.

Thanks for the reply.
Say the expected rotation angle is 20deg.
But it is varying in quite wide range.
So you mean I need to take most frequent data?

What the quality of the lock? Like, how many pixels can it see. The algorithm needs a lot of pixels of the tag for a good measurement.

yeah you are right. When the distance is far a lot fluctuation and get closer, quite ok.

We have a new camera with dram coming soon that can do VGA AprilTags and above. The frame rate isn’t high but it works.