It’s a fairly simple project, too: just hook an Arduino Uno up to a motion sensor and an electronic switch called a relay, then plug in your fan, and you’re good to go.

PIR motion detector module (HC-SR501 or equivalent) C945 NPN transistor D965 NPN transistor 1N5819 Schottky diodes 5-mm white LEDs (generic) 1K2 ¼-W resistors 100K ¼-W resistor 2 Ω ¼-W resistors SPST ...

It is likely that many of us will at some time have experimented with motion detectors. Our Arduinos, Raspberry Pis, Beaglebones or whatever will have been hooked up to ultrasonic or PIR boards whi… ...

We’re still not sure exactly how [connornishijima]’s motion detector works, though many readers offered plausible explanations in the comments the last time we covered it. It works well… ...

Belkin WeMo Switch + Motion Want to control your lights at home from across the globe? The Belkin WeMo Switch + Motion provides a simple entryway into the world of home automation.

Turn on then off Turn on/off it motion detected (this one obviously requires the motion-detector) This rather basic-sounding set of rules is surprisingly powerful. Let’s take an example.