Harmonograph in action

A harmonograph uses two pendulums swinging in perpendicular planes to create a graphic representation of harmonies. This device uses the same relationships found in musical harmonies, but at the much lower frequencies of pendulums. The design for this harmonograph came from “100 Amazing Award Winning Science Fair Projects“ by Glen Vecchione, with minor alterations during the build and test phases. Another interesting book on this topic is Anthony Ashton’s “Harmonograph: A Visual Guide to the Mathematics