[Mellow_Labs] wanted an Everything Presence Lite but found it was always out of stock. Therefore, he decided to create his own. The kit uses a millimeter wave sensor as a super-sensitive motion tracker for up to three people. It can even read your heart rate remotely. You can see a video of the project below.
There are a few differences from the original kit. Both use the C4001 24 GHz human presence detection sensor. However, the homebrew version also includes a BME680 environmental sensor.
If you haven’t seen a millimeter wave sensor—often written mmwave—before, it is essentially a tiny radar that can measure movement, acceleration, and angles very accurately. They are available at different microwave wavelengths and have onboard processing to easily provide useful information for a processor like the one in this project. The processor on board is an ESP32, which works well with [Mellow_Labs’] home automation system.
A 3D-printed case rounds everything out. Circuit-wise, there isn’t much going on since everything is on a module PCB. You essentially just have to connect everything together.
These sensors can do a lot of things. For example, inspecting pipelines. Another common way to detect people is to use a specialized camera.
Multi-colored LEDs lighting up his parts bin, cool!
Did I miss something or the sensor is in the wrong side of the door? I mean why turn on the light once you already been hit by the robber?
sensor works through doors
Can confirm wydmynd’s statement, at least for indoor doors with gaps at the bottom, hardwood floors, and a cheap Amazon mmWave presence sensor. My bathroom light will turn on once I open the first closet door while the bathroom door is still closed (both are aligned with the presence sensor). Might even do it before I open the closet door since it takes a while for the switch that I see to turn on (the switch I see is turned on due to a Google automation for the switch that the presence sensor turns on through a different Google automation).
I’ve been experimenting with mmWave presence sensors. Most options do not implement people counting in the sensor board, and the few devices offering counting are only accurate up to 3 people.
Inspecting pipelines hyperlink links to this article. Awesome advertising.