Why is precision of the camera position is so low?

[keszegrobert]

I can see in the video and also in my environment (https://github.com/keszegrobert/ros_robotic_arm) that the camera's position is not so precise(±2 cm), and this precision doesn't change even if the camera sees more markers. I would like to improve the precision, but need a little guidance to do this.

[CesMak]

Hey, unfortunately I am at the moment not actively working anymore on this project.
Best would be to print the markers in high definition and glue them precisely to your wall - especially the edges!
This usually has a great effect!
Did you consider to use a kalman filter and include info from your wheels position as well?

[keszegrobert]

Hi, I have investigated a little bit and looked at he code. The problem is that the code considers the nearest AR tag as its main source of information and if another one becomes the nearest, it will reconsider. I think it would be much more precise if we would compute camera's position from every visible AR tag, not only the nearest one. I don't know the mathematics beyond this approach, but maybe there is a study out there, which computes the camera's position based on every visible marker.

[CesMak]

Hey @keszegrobert ,
that is a very good Point! Would be cool if you can test that on your end and share with me the changes (pull request) so that everyone can profit from your improvemements :). I guess it would be best to put every new marker into the kalman filter and define for each marker a certainty value!

[keszegrobert]

I will do my best