Wobbling pin gear reduction mechanism

The input shaft drives a disc that is tilted slightly off-axis, causing it to wobble instead of rotating normally.  The pins on the wobbling disc engage with the gears on both sides.  Because the two sides have a small difference in tooth count, each full rotation of the input only advances the output by a small amount, creating a high reduction ratio in a very compact package. For smoother operation, I recommend applying a small amount of grease between the input shaft and the wobbling disc.