How to track many small objects in a small space?

Question

Electronics

Hello.
I can't think of a way to track many objects in an area the size of an ordinary desk (1x2 meters) with an accuracy of 1-2 cm. All objects have an internal number.
There are / were several options:

1. Use of computer vision. Didn't fit, because maybe 2 parts that look the same but should be defined as different
   
2. Using rfid to determine the location - put a label on each detail and already determine the location from it. I saw that this is used on large areas (about 100x100m and with an accuracy of 0.5 m), but I don’t know if such a solution is suitable for smaller areas and greater accuracy
   

Can you suggest a possible solution, or at least suggest which direction to google?
upd: I forgot to point out that all objects have internal unique numbers. Because of this, computer vision options are not suitable.

Answer 1

Use of computer vision. Didn't fit, because maybe 2 parts that look the same but should be defined as different

And what is the difference between them?

Answer 2

Stick a piece of paper with a number on each part and read the numbers using OpenCV.

Answer 3

If they do not overlap each other, then computer vision is also possible. You have to first note which one has which number.
Kinect?
Laser frame?
Still, it would be easier to help you if you did reveal what these objects are.

Answer 4

How is it done now? How do people distinguish them? If you do not give answers to these questions, then there is nothing to automate.