Problem

Racoons are a recurring theme now, on this blog. However, this time it’s more more sinister. They’re not knocking over garbage, they’re defecating in a pool. It was really gross. The last time Racoons gave me trouble, my solution was to rig a sprinkler to a motion sensor. That wasn’t a safe setup, however.

Solution

This time, I thought I’d go with something smaller and safer but still cool! I went with this water gun. and this PIR motion sensor and then just a low volt. relay and an NPN transistor. And just to make it seem a little more stock and easier to use. I built the motion sensor into a Nerf rail attachment so that it was easily removable as well.

The figure on the left is a quick schematic of the circuit used.

And finally, here’s a build gallery with probably enough detail to recreate this, if you like! :)

Build Gallery