Arduino Catbot

We have 3 cats and 3 dogs in our house.  Whenever I go to bed, I can hear the little monsters walking around on the counter.  This drives me crazy and I wanted to find a solution.  What better way to keep cats off the counter than an Arduino?

First off, I know you can buy something to easily solve this problem.  That's not nearly as fun though.

To start, I picked up the Parallax Ping Sensor.  This thing sends out a sonar wave to detect any object in front of it.  It then returns back a measurement that I can convert into inches.  I mounted that on top of a 180 degree servo that I spin around.  To save power, I only trigger it all when my motion detector is set off.  Since these things will sit on top of the counter, they should only trigger when a cat jumps up.

The plan is to shoot a water gun at the intruder (cat) until it is gone.  I'll be mounting the water gun on top of the servo and ping sensor, so it will always be pointed in the direction of the intruder.

Once the final design is complete, I'll build 3 or 4 of these things and leave them around the counters.  That should teach them not to jump up there.  Long term plan is to network them and have them signal eachother so they can work in unison.  I think I can keep this simple and use some kind of IR signal.  Once that's all working, maybe I can even put one on wheels and have it patrol the kitchen.

So much to do, so little time.