Students were asked to design and make a system and object that displayed properties of periodicity. Periodicity occurs when the same pattern of events is seen to run through a higher development as has been contained in a corresponding pattern from a lower sequence (Gowan). For example, periodicity was helpful to Mendeleev, the designer if the periodic table, because it showed him gaps in the table where elements should be. This helped scientists find new elements because they could be expected to display certain characteristics based on the location they would take in the table. Now that the elements have been discovered, scientists and students used periodicity to make predictions about how elements will behave in chemical reactions, and their physical properties (Helmenstine). Periodicity is also present in the phases of the moon and we can observe the pattern of a periodic travelling wave in many other natural phenomena, such as bird population fluctuation, electro-magnetic solar activity and the menstrual cycle. 

Fabio Fidanza, Arman Ataman, Christian Pecher, and Yiming Yang imagined an alien race whose only means of perceiving the world was through visual periodicity such as repeating patterns in architecture, fabric, and images. The design consisted of an aluminium helmet housing a computer vision vision system that sonified the characteristics of a visual grid depending on its density and colour. The helmet was very well finished and the technical achievement considerable. More thought to sound mapping would help make the work more legible. An interesting paradox here is how the design requires its user to imagine she is an alien – what then should sound affordances entail?

Phillip Quiza, Samantha Selin, Hengshi Kang, and Leah Mentzis also used computer vision to register ‘players’ in game of projected coloured circles. The idea here is that each person appears as an orange dot. Orbiting blue dots around the orange evoke the periodicity of the planets. Consensus seemed to suggest that an alternative version with orbits shown as circulating trails helped to understand what was happening. The unreliability of image recognition systems was a key factor here, especially given the lack of control over latency and spatial arrangement.

 

Pierro Pozella and Vivek Muralidhar showed a large inflated white balloon around which white chalk was arranged. This was then bounced, kicked, and slid across the floor leaving faint white trace marks. Inside the balloon were two more sizes of sphere, the smallest of which flashed blue on impact. The concept of spheres within spheres in a changing kinetic relationship to each other nicely embodies some of the characteristics of periodicity but the group felt the system was hard to understand since we could not see the inner shapes.

Jessica Scalzo, Miyuki Oka, Yi Tian used a laser pen fixed to a rotating spiral to draw light patterns around the room. The work featured a double instance of periodicity; one, speed of rotation; two, the elliptical pathway of the light oscillation on the copper spiral. An interesting effect here was that the patterns were invisible to the naked eye and could only be captured using long exposure photography. The group had initially planned for the laser pen to expose photographic paper or to paint light sensitive emulsion directly onto the walls of the room. Constraints of time and cost prevented this, but the group worked very hard to master unfamiliar technology.

Overall, a deceptively complex subject was handled with diversity of means and sensitivity to audience. Periodicity is close in concept to resonance, involving frequencies, scale and repetition. As we progress it will be fruitful for students to integrate or investigate the difference between the two phenomena.