Piezo Hacks

Here's a fantastic project using an arduino, a motor, and a piezo sensor which allows you to both record and detect knocking patterns to unlock a door.  The video below does a fantastic job of demonstrating how it works: It's completely mobile...

Using some piezo sensors, this DIYer created some DIY midi drums for the Arduino. �All it takes is a handful of the sensors and a few resistors to put together. �He's already assembled the soruce code, parts kit and detailed instructions so you...