You'll have a bit of control over what you choose for the motion sensor, motor, and jumper wires. You can pick up a pack of six SG90 motors from Amazon for a little under $12. A 10-pack of the HC ...

An Arduino is a popular open-source single-board microcontroller. Learn how to program one and let the possibilities take shape. By The Big Book Of Hacks Published Jan 10, 2013 3:00 AM EST ...