‘Polagons’: A tool for framing colour-changing mosaics

For inspirations and aspirations to prance out of fantasy novels and sublimely narrated podcasts, we require, in addition to the adeptness of mind and hand, the expertise that comes with a scientific disposition. An understanding, hence, of technical aspects pertaining to one’s field of interest and practice then becomes imperative. It is for the same reason that architecture students are introduced to the study of structural design, artists are encouraged to not only scavenge for natural entities which can become a source of desired colour pigments but also the modes and methods of extracting them, and designers are expected to understand the behaviour of the materials they work with as well as the technique of taming them with the help of industrial tools.

However, while some tools and techniques aid the process of design, a few technologies steer and define the course of creation. One such invention, or rather discovery, is the ability of regenerated cellulose to create polarised light mosaics. A new design tool, namely Polagons, developed by MIT researchers (led by Ticha Melody Sethapakdi, a Ph.D. student in electrical engineering and computer science and an affiliate of the MIT Computer Science and Artificial Intelligence Laboratory), enables the creation of colourful light mosaics that can be printed on cellophane ‘to make data visualisations, passive light displays, mechanical animations, fashion accessories, educational science and design tools, and more.’ Other collaborators on the research project include Laura Huang, Vivian Chan, Mackenzie Leake, Stefanie Mueller, Lung-Pan Cheng, and Fernando Fuzinatto Dall’Agnol. The group has also recently published the paper Polagons: Designing and Fabricating Polarized Light Mosaics with User-Defined Color-Changing Behaviours, delineating the technicalities of their research.

The usage of cellophane sheets in particular is due to the presence of a property called birefringence, which polarises the light that passes through it. Cellophane sheets of different thicknesses deflect light waves at different angles. Utilising this phenomenon, Sethapakdi, along with her colleagues, designed the Polagons system. “When the sheets get put into a “sandwich” of two polarizers (material that only lets certain polarities of light pass through while blocking others), they appear coloured. The colours you see depend on different factors in the material, like thickness and the angle of the material relative to the two polarisers. To create that colour-changing effect, you just need to rotate the image, or the polarisers, because then you’re changing the angle of light propagation,” reads the press release shared by Sethapakdi.

Sethapakdi cites her inspiration for Polagons in Austine Wood Comarow, who is touted as the inventor of polage art and was the founder of Austine Studios, a US-based practice. Comarow, during her artistic explorations, discovered that certain transparent materials, despite holding no pigment, light up with different colours when illuminated with polarised light. A statement from her website reads thus: “When I first encountered polarising filter and experienced how it could break light into colours when combined with clear cellulose, I was instantly hooked by the colours and the magic of their appearance and change. I had never experienced anything like it. To me, this changing nature parallels my belief in the essential mystery of existence.”

Since then, most of her practice revolved around the navigation of means that could help control this phenomenon and be harnessed for the creation of a new artistic medium. While Comarow passed away in 2020, due to ovarian cancer, her work stands tall as a potent example of the limits that can be transcended when art and technology are brought together deliberately. The late artist’s powerful statement about her work further illustrates, perspicuously, how curiosity linkages the worlds of art and science: “My work primarily explores the environment, focusing on ‘invisible’ nature—what we don’t notice because we don’t take the time to look. I love to study the architecture of a leaf, stare at a twig to learn how the buds are set, or depict the iridescent colours in a butterfly wing. I translate what I see into images that incorporate movement and change. I often juxtapose two subjects, not in space like a diptych, but temporally, creating two images that occupy the same space, emerging separately in time.”

Further delineating the role that Comarow’s practice played, in inspiring the MIT researchers to create Polagons, Sethapakdi narrates, “I was really impressed by how Austine Wood Comarow was able to create these intricate, colour-changing mosaics using everyday materials (i.e., cellophane and polarising film). As I learned more about the artistic process, I found that these mosaics were meticulously made by hand, and being able to craft them at the same level as Comarow requires many years of practice. After finding out that the colour-changing phenomena can be modeled mathematically, I saw an opportunity to build a design and fabrication system that could help users create these mosaics more easily.” The intent behind the creation of Polagons was, hence, the democratisation of the art of creating colour-changing mosaics.

Sethapakdi says, “In creating this system, I was mostly interested in democratising this art form and helping preserve something that might only be accessible to skilled individuals. If something happens to the creator of this layering principle, Austine Wood Comarow’s family, does the art then die with them? I think there is a real benefit to building these systems that democratise niche art forms. We hope this tool can expand the community of modern polarised light mosaicists. Since we are making this process accessible to a larger group of users, it can add new programmable material to the palette of options in [human-computer interaction].”

Polagon's computational design system comprises a design tool and a codified fabrication process that requires minimal assembly by the user. Polagon's toolkit allows users to design and visualise colourful mosaics made from cellophane. Users are first required to choose a design template that best befits the complexity of the mosaic they have in mind. Upon choosing the template, the user is led onto another page that displays the varied appearances that the Polagon can embody. During this step, one can also create their own mosaic designs and import them as SVG files. The Polagon Studio then recolours the different pockets of the mosaic to the closest colours possible with the user’s cellophane. Upon hovering over the different swatches of colours on the composed mosaic, the users are intimated about the material requirements (such as the type and number of sheets needed) essential to achieve the colour. One can refine and change this palette by juggling and specifying the cellophane type in the filter category.

Once the user is satisfied with the design and colour palette of the mosaics, they are, once again, introduced to a series of Polagon templates, from which they can finalise the ones that they would like to create physical versions of. One may also interact with the virtual Polagons—rotate the concentric sub-parts in order to witness the changing appearance of the mosaic. Additionally, a 3D CAD plugin within Polagon Studio enables the user to project these compositions upon objects such as sunglasses, clocks or decorative showpieces. Once satisfied with the results, these designs can be exported for fabrication.

The fabrication process entails the placement of cellophane (of required thickness) upon an acrylic base and the execution of laser cutting and welding on the sheet. The excess cellophane is then removed and the process of cutting is repeated with another sheet (placed upon the previously cut parts) until all fabrication components are cut. In the end, one is left with a cohesive mosaic, cut and splintered in the shapes preset on Polagon Studio. The final mosaics are dynamic creations. Their components can be individually rotated and slid across other sections of the Polagon to achieve different compositions.

Sethapakdi further explains the possibilities of upgrading the Polagon Studio, “The computational backend of our system has the ability to support ‘advanced’ use cases which we have not yet explored. For example, if a designer wanted to change colours in their mosaic after fabrication, the system can tell users the minimum number of cellophane layers that need to be added or removed to achieve their desired colour. While our work uses a 2D fabrication process, we also believe that our method can be extended to work alongside a 3D fabrication process (e.g., 3D printing). This would give us more control over the colour palette and support more complex geometries.”

Polagons has certain limitations, too. It cannot help produce all the colours. However, the team believes that further experimentation with the fabrication process can, perhaps, help build more hues. This would essentially require the inclusion of more variations of birefringent materials in the module. On being asked about some of the challenges faced by the research and design team pertaining to the project, Sethapakdi shares, “We had to develop our own computational fabrication process. We chose laser cutting because laser cutters can be used with a variety of materials, including delicate ones such as cellophane. It took a while to find the right laser cutting settings because of the delicateness of cellophane: we needed to ensure that the heat from the laser was high enough to hold the layers of cellophane together, but not too high that the cellophane breaks down.”

The potential of Polagons is limitless. Since it does not require electricity or stored power to function, it can be used in spaces where the transmission of current is difficult, such as underwater nooks, higher terrains and remote islands.