Inkjet Pendulum
Mercer University Physics
The support constrained pendulum produces beautiful artforms. When configured with an x-y recorder to produce patterns such as the examples provided on the Mercer Physics webpages, the traces are black and white.
A previous version of this "science as art" pendulum used an inkjet impactless timer (IJIT) mounted on one end of a rigid boom, the other of which was attached to a universal joint. As this pendulum swings, its motion is mapped by the microdots of ink that are dispensed by the IJIT, one droplet every 50th of a second. The resulting pattern has an additional feature of diversity--a complex Moire type structure that results from the following: where the pendulum speed is low, the dots are closer together than at those places where the speed is greater.
The students of this project will build a color version of the IJIT, in which a Hewlett-Packard color inkjet head is used instead of the black and white dispenser. By switching on the various combinations of the primary colors (magenta, cyan, and yellow), any color of the rainbow will be possible. Moreover, the colors can be altered as the amplitude of the motion decays. If you find the black and white cases interesting, then it is expected that you will find the colored patterns to be nothing short of magnificent.