Tracking Precise Object Location

Question

I am trying to track the precise location (within 1 mm) of up to about 200 objects within an area of about 2 meters.

Factors:

1. Accuracy needed - within 1mm
2. Number of objects - 100-200
3. Area about 2 meters squared.
4. Objects are mostly stationary but may move.
5. No need to track speed or read the movement in real time but new location the object moves to needs to be established.
6. Line of sight will not always be possible so computer vision / cameras aren't super viable.
7. Would hopefully be able to make it for max a couple of hundred dollars for hardware (readers and tags etc...)
8. Tags need to be small and unpowered.
9. x, y, z axis position ideally would be known.

I have looked into both passive RFID and UHF reader and magnets with magnetometers but I'm struggling a bit to understand where to start with either / both. How many antennas for RFID, which models of readers and tags would you recommend? For the magnets, how many magnetometers and if you know any make and manufacturers that could work.

Any help would be super super appreciated.

Thanks so much!

Answer 1

I don't think that this is possible. Such an accuracy is not realistic. Just think about the orientaion of the tag antennas and how that influences the radiation pattern. On top there are tolerances of the individual tags.