Science East harmonograph

Abstract

A harmonograph is a device that uses swinging pendulum motion to draw complex geometric patterns, known as Lissajous curves. This device is typically found in many science exhibitions all over the world. We have been tasked by Science East to design and build a two-pendulum harmonograph. The new device will replace their existing three pendulum harmonograph which is prone to continuous failure due to defects in its structure. The new design contains gimbals as pendulum pivots allowing the range of motion required and steel for general construction to improve overall robustness. Calculations have been performed to demonstrate that the selected pillow block bearings will not wear out during the device’s lifetime; pivoting joints will not be at risk of failure due to stresses imparted, and that the table will adequately support the device and other additional stresses caused by visitors to the center. Construction and testing have proven the device works as intended meeting the client’s requirements.