I love my cats. But they can be really annoying... One of them tries to enter our bedroom every day at 5am, by scratching the door. I want to be able to stop it!
That's why I created my water-spray!
It's based on an Arduino Pro Mini at 5V, an HC-SR04, a small stepper motor (modified), an L293D H-bridge, a micro-switch and some 3D-printed parts.
You can find all the steps, trials and source code on IoT-Experiments.com