Looking for some guidance for an automatic pet feeder

So, I just received a few arduinos for x-mas and i've just found some time to start looking into them. My girlfriend's cat wakes us up at 5 A.M. daily to make sure we feed him. Nigel (her cat) also doesn't know how to ration his food if we go away for more than 24 hours.

I'd like to make an automatic pet feeder that has some sort of internet connectivity to a web app or server of some sort to send commands to feed him. I have an ethernet shield, but I'm not sure where to start. I've been watching some videos but I figured I should come here first. Any suggestions, tips, help, etc would be greatly appreciated.


Break your problem down into a series of smaller problems and solve them individually. As you already have the ethernet shield, I would start with that. Connect it up and find the libraries for your shield. Most libraries have an example of a web server, where the Arduino waits for an incoming web request so start with that. Once you have the example working, see if you can start changing it so that you can send a “FEED” request and receive it successfully on the Arduino.

Once you have all of that working, you can move onto the hopper for the food (I assume it is dry food).

And test, test, test. Turn the power off at multiple, random times, that sort of thing.

NodeMCU + A 3.3V relay board + solenoid + 12V power adapter (for the solenoid) and one with a USB out (5.5V) for the NodeMCU board would be nice.

The NodeMCU board comes with an ESP8266 IC that makes wireless internet connectivity a breeze and there are plenty of online resources for how to get one up and running.

Step 2 is to have a basic web-page that you can update…it would only need to change to say “feed” on the main page.

When the NodeMCU “GETS” the webpage, it reads the contents…if it sees “feed”, it turns on a GPIO pin to trigger the relay board/solenoid that will release the food.

For simplicity, you could have multiple relays and solenoids to a “packet” from a multi-compartment food hopper is released at different times.

12V relay board (should be able to be triggered with 3.3V logic)

NodeMCU - 80MHz with Wifi! Can use Arduino IDE to program…and uses many arduino libraries.