This is my latest automaton. It picks up knex balls and eats them.

It has two moving arms, a head that turns, and a mouth that opens.

If you're making this, make sure you have at least 4 ball joints, 2 ball sockets, 2 hinges, and 4 pulleys.

Step 1: Base

This is the base of the automaton.

Step 2: Scaffold

This part will hold the motor.

Step 3: Motor and Crankshaft

I'd recommend using the motor where the battery pack is separate from the motor.

Step 4: Adding Motor and Crankshaft

This is how the motor connects to the scaffold.

Step 5: Bearings

These wheels will help keep the head on straight.

Step 6: Neck

This is the main axle. It will turn back and forth.

Step 7: Adding the Neck

This part fits in the middle of the bearings.

Step 8: Spine

These are all the parts that will go on the main axle.

Step 9: Adding the Spine.

Pay careful attention to the direction of each part on the spine.

Red connectors are used because they make the right arm go further than the left arm. This is needed because the crankshaft makes the left arm go further than the right arm.

Step 10: Adding the Base

The spine will go through the white connector in the base.

Step 11: Arms and Shoulders

Step 12: Adding the Arms

The Shoulders are connected to the Scaffold, and the Arms are connected to the Spine.

Step 13: Head

Most of this step can be replaced later.

Step 14: Finished!

Add the Head to the Neck, and attach the back of the head to the scaffold.

Now you're done! Turn on the motor to make sure nothing is jamming. If it is, go back to step 9 (adding the spine) and make sure everything is pointing the right way.

Step 15: Entrance and Exit Tracks

This is an example of an entrance and exit track. I'd suggest making your own. When you design your ball machine, try to avoid the need for the scaffold in this step.