Almost everybody knows them: the bird mobiles where you pull a string to make it flap its wings. But what if we can automate it? My wife and myself gave it a try and came up with this:

In this instructable we will build the bird and automate it so that it works on 110 - 230V DC. We also entered this instructable in the kinetic sculpture contest so if you like it then please vote for it. Thanks

Step 1: What Do We Need?

For this instructable we need:

Cardbord: We used 3 layer cardbord for this project.
Fabric: We used plain white cotton fabric (also known as an old sheet)
A Weight: How heavy?? Well that will depend on your bird so you'll have to wait until you finished it before you find that out.
Fishing line
A 110V or 230V motor with reducing gears: Our rotates at about 10 RPM
Electrical wire and plug
some plastic or wood or metal: to make an arm
A spacer or a screw
Scissors, needle, tread, glue
Some clothespins

Step 2: Make a Design

Making you own design full-scale can be a bit daunting, so it's better to start with a small drawing. The drawing that you can see in the first picture is only 9 x 9 cm.

When you are happy with the design, you can devide the paper in squares of 1 by 1 cm.

On the cardboard you should draw the same amount of squares but 10 x 10 cm. This makes it easier to transfer the design on the cardboard and scale it up at the same time.

Now you can cut out every part with a pair of scissors or an exacto knife

After this, you need to trace every part on cardboard again and cut those out too. Now you should have two bodies, two tails and four wings.

Step 3: Give It Some Skin and Assembling the Bird

Take your fabric and lay out the cardboard pieces on it. Trace around the pieces at a distance of about 2cm and cut them out.

Then place the cardboard piece in the middle of its piece of fabric and fold the fabric over the rim while you secure it with glue. Do not glue the fabric to the sides or the front.

Give it some time to dry before you continiue.

When everything is dry, you can stitch the 2 halves of each body part together but leave an opening on the bellyside of the bird.

Now stitch the wings together through the body.

You can also attach the tail to the bird by stitching it to the body.

Step 4: Building the Mechanism

The mechanism to make this bird fly is not very difficult to build. All we need to do is to connect the wires of the motor to a wallplug and build an arm on the axis of the motor that makes the bird move up and down.

In my case, I had a leftover pendulum from my Photo wobbler project, but you can use wood or metal if you like. The arm that I mounted was about 10 cm long (measured from axis to attaching point).

I glued the arm on the motoraxis with Cyano-Acrylic glue.

I added an spacer on the arm as mounting point. A nut, glued tot the other end, should prevent the wire from falling of.

Step 5: Bring Everything Together and Make It Work.

So this is the final step in this instructable:

Now we need to string up the bird. For this you will need your fishing wire. Our motor came with 2 ideally placed mounting holes, so we could use those to attach the wing to. On the picture you can see where to attach the wire to the wings. The length of the wire depends on how big your bird is. If you make it to short, then you bird will wobble in a strange way when the arm goes to the left or right side. When you make the wires to long, you might find out that your ceiling isn't heigh enough.

When this is done, you can attach a string from the back of the bird , straight up to the mounting point of the mechanism. Make a nice loop on that side so that the wire doesn't wind up itself when the arm spins around.

When all this is done, you can test your bird and you will likely find out that it doesnt hang balanced. That is why we left the belly open. Attach some clothes pins to the bird until it hangs as you would like it. Then calculate the weight of those pins and find yourself something of the same weight. Add this weight inside the bird and now you can close the belly.

Attach a string to the mechanism so that it can hang from the ceiling and you are done!!!

Ofcourse you can add all kinds of decorations to the bird (thats up to you), but you should add them before you balance the bird.