This pet bowl opens when the animal with the receiver approaches it and stays closed for all other animals.
Step 1: Circuitry Used
I was asked to make a "special" pet bowl by a friend. She has two cats. one is over weight and eats anything left out and the other is too thin and would eat more if the food was available all the time. So, I made a bowl that will only open for the skinny cat.
This is a luggage alarm. You're supposed to put the little fob in your luggage and keep the big receiver. The receiver will vibrate and beep if your luggage gets a certain distance away from you
Step 2: Circuity Used
Since this system uses about an amp it needs to be plugged in instead of battery use. So, there's a 6V regulator. Two SPDT relays are also used as seen in the diagram.
And, since batteries aren't used it's a perfect spot to put the luggage receiver so I can get tothe sensitvity adjustmen without taking the bowl apart.