Using a Raspberry Pi Acmecorporation made this Automatic Pet Water Bowl Project. This project is designed to keep your pet bowl filled with fresh water and also gives you the ability to keep an eye on your furry friend. The designer is a native french speaker so there are a few spelling mistakes but his English is much better than my French.
“During the summer, when i leave at home my dog for several hours, i have the problem that water inside its bowl become warm in few time. Then i’ve create this system that can empty and re-fill the bowl with fresh water each preselected time, maintain constant water level and finally spies my pet.”