ABSTRACT
Cycloidal mechanisms can easely be tailored to provide one of three common motion requirements: intermittent motion, with either short or long dwells; rotary motion with progressive oscillations, where the output undergoes a cycloidal motion during which the forward motion is greater than the return motion; or rotary-to-linear motion with a dwell period. All cycloidal mechanisms are geared. This results in compact positive devices capable of operating at relatively high speeds with little backlash. It is not always realized that cycloidal mechanisms can be replaced by other types of cycloidal mechanisms that produce exactly the same motion and yet are more compact. The kinematic equivalent mechanisms of epicycloids are pericycloids, in which the planetary gear is stationary and the output is taken from the ring gear. Such arrangement usually lead to a more compact design.
