I recently had to build an infrared close proximity sensor that could tell if something was dropped in a parcel delivery drop box. After some searching, I ended up using a microcontroller and a piece ...

[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors ...

In the microcontroller era today, Arduino is more than just a tool to accomplish hobby tasks. There is actually a close relationship between microcontroller technology and home security, since you can ...

Unlike infrared optical sensors that use an LED transmitter and IR receiver, the PIR emits nothing. As its “passive” name suggests, it responds only to infrared energy radiated by the object being ...

Some readers may recall building a line-following robot during their school days. Involving some IR LEDs, perhaps a bit of LEGO, and plenty of trial-and-error, it was fun on a tiny scale. Now imagine ...

Passive InfraRed sensors (PIRs) are electronic devices which are used in some security alarm systems to detect motion of an infrared emitting source, usually a human body. All objects, living or not, ...