Introduction: Sleeping Cat

Does your landlord not allow pets? Are you so anxiety ridden and feel a burnout creeping up on you that the only solution seems the warm embrace of death or the sight and presence of a sleeping cat?

Well honey, have I got the project for you!

With this project you'll be able to build a sleeping cat that 'breathes' and moves it's tail after touching it's paw.

Step 1: Requirements

The requirements for this project are pretty simple. You will need:

Arduino parts:

  • 1 Arduino Uno
  • 1 Breadboard
  • 1 Circuitboard
  • Male/male jumpercables
  • 1 10Ohm resistor
  • 1 Photoresistor
  • 3 Servo's
  • 1 9V battery
  • 1 9V Battery clip

Crafting parts:

  • Cardboard
  • Iron wire
  • Tape
  • Soldering iron
  • Glue
  • Paper Mache
  • Soft, fur like fabric

Step 2: Wiring & Coding

Wire your board and modules as in the example above.

Download the arduino file containing the code. Upload and run it.

Step 3: Soldering

Convert your breadboard setup to your circuitboard and solder all the wires. Make sure you use long jumper cables between your circuitboard and your photoresistor since we're going to be placing it somewhere else.

Step 4: Housing Assembly

Take a big piece of cardboard and sketch the outline of your cat. I made it about 50 x 25 cm but just to be careful you can always draw a but bigger. I used the picture above as reference, you can find the source here:

Once you're done sketching use your iron wire to build a wireframe of your cat. I taped it to the cardboard for stability. Make sure to keep enough space on top and above the hind legs since there will be servo's located there.

Cut out the carboard on the inside of your wireframe, then, cover the entire wireframe in paper mache except for the holes we left open on top, above the legs and at the tip of one of the hind legs.

Now is a good time to make the little flap/cover for the big hole on top, this is what the servo's placed there are going to be pushing against to create the effect of ribs moving, and thus creating a breathing effect. I, again, made a wireframe first and then covered it in paper mache.

Once your paper mache has dried, cut out the entire mold from the cardboard only leaving a little line of cardboard where the wireframe is taped to it. Cover the entire thing in one more layer of paper mache, pay close attention to the edges because if you don't cover that up it will get loose in the future.

After that layer is dry take another piece of cardboard and trace the contour of you cat onto it. Cut that piece out. Mount your Arduino uno and circuitboard in the center of the piece of cardboard you just cut out. Make sure you have enough space on all sides since we're going to be mounting to servo's on top of it. I recommend you put the 'lid' of your case (the paper mache cat mold) on tom a lot to see if it fits. After that, build a little table on top of it, this is where the two servo's go. Make sure it's pretty solid since the servo's are going to lift pretty heavy stuff.

Tip: secure a lot of your stuff with iron wire, for example, the little table the two servo's are going to be mounted on!

Build little tower about 5-6 layers of cardboard thick and place them on top of the table, secure them tightly. Place your two servo's on top, make sure the little propellers are placed on the sides of the towers so they have space to move, as shown in picture 6 above.

Now take your photoresistor and place it at the tip of the feet, where you left a hole in the paper mache. Make sure it can peek through the whole when the 'lid' is mounted. Tape the wires down securely.

Lastly, build a little table underneath the hole in the hind legs. Place your last servo on top. Make sure it's aligned with the tail!


When all is done, take your 'lid' and cover it in fur like fabric, use a strong fabric glue! Cut a small hole on the bottom of the cat's back where we can put the power cable so your arduino has power. Take a long piece of iron wire and wind it up into a tail, cover that with fur as well and place it at the cat's bottom. Make sure it doesn't cover the hole above the hind legs that exposes the servo. The last step is to take the propeller from the servo above the hind legs and make a attach a little iron wire tail skeleton and attach a piece of fabric to it, this can be done by simply using a stapler. Re-attach the propeller to the servo, aligning the fabric attachment with the tail, this is the of the tail, which is going to be moving when the photoresistor is covered. Cover the hole with a piece of fabric while your presenting your mechanical cat.

Power your arduino and that's it! Congratulations, you've just build a new mechanical pet.