I’ve taken a few different mechanisms and combined them in this new project. Most of the paper animations that I make complete their story with a single turn of the handle. With this design I’m hoping to have four turns of the handle to make one story. Here’s the effect I’m going for: turn the handle and the eagle turns left, faces straight ahead, turns right then faces straight ahead again, each move corresponding to one complete handle revolution.
I’m aiming to make a rather grumpy looking eagle who will look around him and flutter his wings menacingly. The blue shaft will be the main rotating shaft to which the head will be attached.
The Geneva drive makes a nice divide-by-four mechanism. For each turn of the handle the Geneva cross turns a quarter of a turn.
The Geneva cross is then linked to a crank and thence to a scotch yoke. The moving yoke is connected finally via a linkage to an arm protruding from the blue vertical shaft twisting it from side to side. It works well with me holding the parts in place.
The shaft connected to the handle is quite long, you can see it dissapearing behind my index finger in the picture above. Hopefully I’ll be able to connect some sort of cam to this shaft and use it to move the eagles wings.
My next step is to mount the whole thing into a single box.