Human presence sensors....

[skywatch]

Does anyone have any suggestions for a 'directional' human presence sensor?

It needs only about 3-4M range but a 90 degree field of view would be ideal for corridor doorway detection.

I have seen some listed online but I believe that they have a 360 degree sense area and this would not be suitable for my application.

[TheoL]

There are some new AI based radar nodes that can detect human presence even if a the body is not moving. They use an Serial protocol and should be simple tu use. You can setup alarms within several disctances. I'm still not sure if I want that kind of sensors in my house tbh. But it should be a one weekend project to get it up and running
Maybe I will mount one on my desk to control the lights. And one on the outside of my house, but I will not install many inside the house.

[britishbook]

AI-based radar nodes sound like an exciting advancement, especially for security and smart home automation. The ability to detect human presence without movement could be useful for elderly care, energy efficiency, and security systems. Using a serial protocol makes integration straightforward, making it a feasible weekend project for those familiar with microcontrollers. However, privacy concerns are valid—just like with any smart home technology, balancing convenience with data security is key.

[britishbook]

This post is deleted!

[TheoL]

https://esphome.io/components/sensor/ld2420.html I believe the radar model they use is in that artical. It's pretty simple to use. If you preset the zones you get a trigger and read the zone. Not sure if an atmel is fast enough to keep up with the readings of the sensor. But they aren't expensive, they are actual very affordable and fun to play with

[CodeGarage]

I use similar LD2410 with atmel for 4 years now without any problems. Just configure boudrate little bit lower (via PC connection) then use interrupt pin as triger and uart only for changes in config.

[TheoL]

@CodeGarage does it give many false positive or false negatives? I want to mount one under the porch at the frontside. Also did you post this project somewhere?

[CodeGarage]

@TheoL I have cat and no false at all. But it is not simple to proper design of radon for this kind of sensors. I not posted it anywhere, but from firmware side it is straight forward - I use this one https://github.com/ncmreynolds/ld2410 + simple sketch for mysensors.

[TheoL]

@CodeGarage Bot sure what you mean with a proper design of Radon and Google translator didn't help much. I have a big renovation ahead. But after that I should have a 32 square meter hobby space. That one is the first project I'll be doing over there

[CodeGarage]

@TheoL "A radome (a portmanteau of "radar" and "dome") is a structural, weatherproof enclosure that protects a radar antenna."
In other words, it is special designed enclosure. If you want 100% predictable results, it must be good design.

[TheoL]

@CodeGarage I guess I have a lot of research ahead )

[CodeGarage]

@TheoL It's not that hard For me, most challenging part of design was to determine material properties (I was using 3d printing technology).

[TheoL]

@CodeGarage What I want is a lion powered Sensor if possible. And that in a case I can stick to the door frame. As I cannot screw or drill into the doorframe. But I have no idea how much current that draws.