Projects Past: The 2009 Automatic Cat Feeder
In 2009 I took a week off from work to build an Automatic Cat Feeder to ration food to the overweight household cat. This was a project built from need and it had a deadline because my girlfriend and I were heading out of town for Thanksgiving. The requirements were simple: It needed to be easy to refill and dispense the correct amount of food twice daily. Early on I had an idea for a large rotating drum to dispense the food, it needed to be easily removable for refilling and heavy enough that it could sit on a motorized wheel and cause enough friction to be turned. Figuring out a latch mechanism that dropped the correct quantity of food after one rotation was the first tricky part. I didn't want any electronics on the drum so it had to be completely mechanical. In the end I hot glued a small box to the outside of the drum which filled during rotation, when it started moving back towards the top a tab would be hit to fling a door open and drop the food out. A magnet held the