I find that I do a lot of fun projects but I’m very bad about documenting them when I’m done. Holidays are for hacking (in my mind) so I usually plan ahead and do something cool during my time off. This project, which I loving call the Autodine-2009, was a spontaneous event over Thanksgiving that I’m just getting around to writing about.
Our cat’s want to be fed at 6am and are very insistent about it. Like most folks, I’d rather be sleeping at that time of day so I built an automatic cat feeder. Now we sleep while the cats eat. We don’t want to rely on a hack to feed our cats when we’re away so I didn’t go the route of an Internet-enabled multiple-dose feeder. Instead, I used parts on hand to create a single-serving dispenser on a timer. A servo rotates a false bottom to gravity-feed the cat food. The servo doesn’t have control circuitry so it is controlled through an h-bridge (I did have to buy 2 transistors for that) by an AVR ATmega8 microcontroller. There are two salvaged tactile switches to set the time and timer, and a serial LCD display that I’ve had sitting around for years. Power comes from an old cell phone charger a friend had just given me that spawned the feeder idea when I asked myself “hmmm, what can I use this for”?
I’ll demonstrate this recycled device for you in a video after the break. This wasn’t as hardcore as my AVR Tetris build but I’m much happier now that I can sleep in a bit.
