I want computing to be tangible and accessible. By “tangible,” I mean I want students to be able to see, as much as possible, how a computational artifact comes together and/or interacts with the world. By “accessible,” I mean I want students who don’t consider themselves “computer people” to have opportunities for positive and meaningful interactions with programming and/or other computational technologies.

Just before break, a colleague asked me if we how hard it would be to develop a sensor that students studying Environmental Science could use to monitor light and temperature levels around a building, both on a fixed schedule and when motion was detected. (The answer: it takes 120+ hours of research, design, development, and testing.) Last year, first-year students build a cardboard computer — an Arduino glued to cardboard instead of soldered to a PCB. Building on that idea, I developed a sensor that would achieve the stated goals while also allowing for all of the major components (processor, sensors) without difficulty. The original board design looked like this:

The board design was done in OmniGraffle. The gray areas are velcro (for attaching the board to the enclosure), the gold areas are copper tape (making it easy to bring several ground wires together, for example), and the rest are wires that students would solder between various connectors. They would print the board, glue it to a manila folder, cut it out, punch holes, and start gluing headers to the board; I expect the total assembly time to be between 3 to 4 hours.

Now, the substrate leaves something to be desired: it is floppy and a bit annoying to work with. Further, it is tedious to punch holes through the board for every header connection. And while I like the fact that there is a certain amount of craft involved, I’d like to cut some of it down. So, I went looking to Ponoko, to see if I could laser cut the board.

I hadn’t used Inkscape before, but it wasn’t too difficult to get the hang of. The color blue indicates a cut through the material, gray indicates raster surface engraving, and green indicates vector engraving. (Letters are vector engraved.) Now, here’s the kicker. The material (cardboard) cost $0.41 for a 7″ x 7″ piece. This is fine. The laser work costs $2/minute, and my design will apparently take a little over five minutes to engrave and cut, meaning the laser work costs around $11. Handling is about $5, and shipping around $4, meaning the total cost for a Ponoko laser-cut board is $18 in cheap cardboard. Yes, that is more expensive than designing a PCB and having it produced and shipped in quantities of 10.

All of that said, I wanted to see it would come out, so I went ahead and ordered one. The reason? I want a laser cutter. A laser cutter is an incredible tool for crossing disciplinary boundaries. I can have students engraving parametric equations from their multivariate calc class onto balsa surfaces, capturing (cheaply, but robustly) the most beautiful 2D and 3D equations they can design. Or, we can explore paper cutting, or using more robust (cardstock), have students in Theatre doing scene design just like the pros. There are no end to the applications in Art. It would be a powerful tool for grounding outreach into the community (making laser cutting available to area middle- and high-school teachers and students), as well as a centerpiece for a new hacker/makespace. And, for me, I can be working with students on small-scale robotics using some of the tools that make bespoke and custom robotic work possible.

If I had my own laser cutter, this would have cost $0.41. And, in the end, getting a prototype in-hand is worth $18. But the real power from tools like this comes from having them readily available to make new collaborations and innovations possible.