Make sure the adjustment knobs for sensitivity and on-time for the motion sensor are facing up so you can modify how sensitive your device is and how long it stays on to signal your Arduino.

TK has combined a PIR with an Arduino to create a smart safety light for the house or workshop. Follow along as this gets built out into a more extensive project.

The project’s goal — in excess of a lighting solution for an entrance hallway — was the learn the ins and outs of the Arduino and motion sensors.