If you want an OCCUPANCY sensor, as opposed to a MOTION sensor, the most reliable solution I have found is Hiome.
Hiome
Rethink what your smart home can do with true occupancy sensing that just works.www.hiome.com
I've been using them for over a year now, and while the first few months were a little rocky (occasionally missed my entering or leaving a room) I guess they (silently, I never had to do anything) updated the firmware because now they are very reliable.
They appear as HomeKit Occupancy sensors, and I use them for exactly what you want. Basically my home setup is
- some lights go on in the afternoon (based on a Hue light sensor)
- all lights come on an hour before sunset (but many of them to 30%)
- when I walk into a room the 30% goes to 100%
- when I leave a room a timer starts and, after 3 minutes, they revert to 30%
To get this fancy you also need Homebridge (to provide HomeKit timers and HomeKit state variables). But for the basic concept you want, the room OCCUPANCY [without having to wave your hands every fifteen minutes]) I've been very happy with Hiome.
Thanks for sharing that info, I will definitely look into it. I was under the impression that an occupancy sensor was just a glorified motion sensor. I will have to look into how it triggers events for entering and leaving.
The reason I like the idea of it being something like an airtag is its small and cheap so it can be added to multiple rooms very easy but if occupancy sensors achieve what I am looking for, that's good too. Thanks Again.