The Geneva Stop, a mechanism that transfers continuous circular motion into intermittent circular motion, is the heart of film projectors and mechanical clocks, and therefore also the most important component of this project.In a film projector, every frame that gets pulled in front of the lens must pause there for a fraction of a second (ie. 1/24, 1/18, etc), in order to be registered by the human eye. The beam of light is interrupted by the shutter in the split second while the next frame is being pulled into place. Therefore, our eyes do not register the time lapse and blurring image in between the frames, and our brain interprets the sequential static images as motion. It is this synchronized relationship of multiple pieces of machinery that I am duplicating. Go here for a great animation explaining how this mechanism works. Go here for more information about film projectors and movie camera technology.
I first built a working model out of MDF, and then was lucky enough to buy a real one from a junk collector. I subsequently fabricated the aluminum housing that holds it together, and modified bicycle gear hubs to mount to the shafts on both the input and output ends of the Geneva Stop.
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