How to Make an Easy Automatic Pet Feeder for Less Than $25!

Hello pet lovers! Are you going on a trip but then think about your pet? That's that happened to me a few days ago. I went online at first, but then backed off when I saw the prices. Well, in this instructable, I will will tell you how to make a Simple, easy and cheap automatic pet feeder with Arduino!

Supplies

1 Arduino UNO. (This one is cheap and inexpensive.) $18
1 micro servo. (Here is a cheap 2 pack) ~$4
Jumper wires (M to M) (Here's a lot of a cheap price) ~$1
3d printer (Optional)
Any food container (Depends) ~$5
Some cardboard (Depends) ~$0-1

Step 1: Making the Circuit

We start by making the circuit. The servo motor acts as a lid to the food container, and the Arduino is the commonly known microcontroller. The servo motor will rotate at a certain angle therefore opening and closing the lid. You can wire it by looking at the picture above. The colors of the wires represent where they should plug into.

Step 2: Building the Physical Object

Option 1 (What I used): 3d print the physical object. Download the files below and 3d print them, or send an email to drjhxie@gmail.com, and I'll send you one for a low price.

First, Glue or screw the base to the stand. Then, attach the servo to the "Assem1_-_SG90_plastic_Horn-1.STL". After that, glue the servo below the two pillars. Lastly, glue the bottle neck at the top of the build. Use the images above for reference.

Option 2 (Not tested, should work): Get a reasonably sized cardboard box or something, and cut a hole about the same size as the servo. Your servos also should come with a small plastic bag containing the "horns" of the servos. Pick the one that is like picture 2. Now cut off a piece of cardboard a bit bigger than the size of the hole you made earlier, and glue it to the top side of the horn. Now you can attach the servo to the side of the box.

Step 3: Testing the Servo

Twist the servo horn without power connected, and it should turn ~175°. If not, change the position accordingly until you can turn it ~175°. Use the 2 (horribly drawn) pictures for reference. (lol)

You could also use the servo tester to do the job if you have one handy.

Step 4: Programming the Arduino

This program should be pretty straightforward. Download the file below, and upload it to your Arduino. Basically, you start the code at 7 am, and it will deliver the food. After 7 hours, it will open again, which is at 2 pm, then at 9 pm, it will open again. Finally, it will wait 10 hours, and it will start again at 7 am. In the code, it will explain a bit more.

The video above is how the build should look and work like! (Sped up to 5-sec intervals for video purposes)