I think you might want to look into https://espresense.com/ https://espresense.com/ Basically, this will net you "room precision" location of people, but i can

I think you might want to look into https://espresense.com/ https://espresense.com/ Basically, this will net you "room precision" location of people, but i can't see why it won't work for gadgets if they have a Tile on them. Not quite "in 3D space", but may be useful enough...