Design and Fabrication

Before even setting out on it, I knew that the fabrication aspect of this physical computing project was going to be about as much fun as it was going to be challenging. I have never worked with CAD software or 3D printing before, and have little to no experience with the design of physical, worldly objects. But the idea of slowly, gradually realizing a physical thing—beginning with no more than a sketch or a hazy idea in mind—is so exciting to me that the learning curve of everything involved in actually accomplishing this realization was almost negligible.

With that said, the single theme that most defines my path working on the fabrication component of this project is that of collaboration.

My initial sketches were inspired by the warped, slightly squashed, orb-like form of countertop essential oil diffusers and humidifiers (although, retrospectively, this form much more accurately reflects that of the new Google Home donut devices). I began modeling these sketches in Vectorworks in preparation for 3D printing. Work on this modeling was difficult, as although I have experience working with two-dimensional modeling software, there is really no comparison between this kind of modeling and 3D.

Chester Dols, a second year student at ITP, was an incredible help to me, and helped me considerably with furnishing the skeleton of the two halves of my orb enclosure. The work was done in Rhino, and yielded two .obj files (one for each half of the orb) and a composite .3dm file.

For the printing itself, I opted to have it arranged at the LaGuardia Studio instead of printing it on the ITP floor. Owing to the dimensions of the two halves of the enclosure, the job would take upwards of ten hours (during which, owing to floor policy, I would have to be present to supervise the printing). So being able to drop off the plans and pick up the finished piece when ready would be hugely convenient.

And it turned out for the best, as there were some errors and inconsistencies in the two obj. files that needed ironing out. The incredible staff at LaGuardia helped me fix the files in CAD software and ready the enclosure for a successful, error-free printing.

The only thing left to do was to determine the nature of the print — such as color, material, printer, and a few other considerations.

I had intended the orb enclosure to be opaque enough for the components inside (i.e. Arduino, battery pack, bluetooth module, Neopixel strip) to remain obscured, but transparent enough for the light diffused by the Neopixel to be visible and relatively vibrant, so it made the most sense to consider a blend of colored and clear material. Namely, a blend of transparent plastic and a sort of ivory white. So, the team at LaGuardia arranged for several sample chips of different ratios of clear to white in the two thicknesses represented in my orb to be printed for my consideration (the walls of the orb are approximately twice the thickness of the thinnest sections at the very top and bottom). This batch included six tiles of 30%, 40%, 50%, 60%, 70%, and 80% white to clear blends.

I decided on the 40% ratio, as that was the best compromise between opaqueness and transparency. With the details set, the printing was ready to begin.

Upon picking up the print job just ~4-5 days later, I had my first alarming setback of working on this project. The orb was printed at half scale, and could only barely accommodate an Arduino board, and most definitely could not have accommodated the Arduino in addition to the other components necessary for its intended functioning.

3D printing can be a finicky venture. Between the complex files that dictate the printing, to the delicate machines that accomplish this work, a large number of things can go wrong. Luckily, we were able to print at proper scale before the day of presentation…

 

Leave a Reply

Your email address will not be published.