We've got the whole workstation availability thing licked, but I want to be able to show our users which study seats are available here in the TFDL. That's one of the top two most common complaints here; that students spend too much time wandering around looking for a place to sit/study.
Here's my stream of consciousness on the issue. The solution can't be built in to the chairs, because those can move from table to cubicle etc. I think the most accurate bet is going to be a small proximity or motion detection device at every single table top, either above (subject to being blocked by study materials) or below (subject to confusion by a pushed-in chair?). The problem with that solution is cost and infrastructure. Unless very efficient, each unit would require electricity and a wifi transmitter. Building or buying and maintaining several hundred small Arduino-like devices seems too cumbersome and expensive.
Some other ideas I've come up with, or that have been suggested by colleagues, include cameras that can monitor a large space and tell which spots have bodies sitting at them. Possibly IR cameras? Tracking the number of active wifi connections on a floor, or around a particular antenna, and then guestimating that there must be a certain number of available seats, though not able to pinpoint them on a map.
Are you aware of any solutions out there already?