Harmonic Drive

A working educational model of a "Harmonic drive" also named a "strain wave gearing" using a 3/4" chain and some plexi. This one has a gear ratio 1/5. The chain counter-rotates in a wave form, almost moving like a serpent... it works rather strange and funny, but they are used in high tech gear applications. more info : http://en.wikipedia.org/wiki/Harmonic_drive animation on : http://www.youtube.com/watch?v=lstQwLbAG0g