Animations of mechanical models

Original model

(7)-1 Multiple trammel gear (2)

A ditch is cut every 60゜in the dark purple disk. Two arms are connected to the handle's axis, and the tips of the arms have rollers moving inside of the ditches. Axes of the disk's and arm's rotation are parallel, and the distance between the axes is equal to the radius of the arm's axis. Two rotations of the arms translates to one rotation of the disk. [Animation: DI JING, Graduate school of informatics, Apr 2000]