Remember the components I picked up a few weeks ago? Some of those have already found their way into projects. Some of them, more specifically sixty-four of the hundred red LEDs, are now part of a three-dimensional LED matrix powered by an Arduino Uno. This is something of a milestone for me, as it was a video on the web of just such a cube that was responsible for rekindling my childhood interest in tinkering and building things like this from scratch. Having completed the project and run a few different program routines on my LED cube, I can now move on to bigger and even more complicated projects.
What follows is something of a photo montage documenting the build process of my 4x4x4 cube. I didn't take nearly as many photos as I should have as I decided to enjoy my quiet weekend evening inside instead of burden myself documenting every single step. Additionally, many of these were taken with my smartphone as my hands were dirty, so I apologize for their poor quality.
At this point I was only just starting to connect the first layer of the cube. I took a lot of inspiration from the guides found on instructables.com, though one I found especially helpful. I used some spare material, specifically cardboard, to serve as a jig to hold things together while soldering. However, unlike most of the guides out there that offer templates to print or exact measurements to mark, I punched holes in the cardboard using nothing but a visual rule of thumb. Turned out just fine!
Having finished two layers, I decided to solder them together for a quick test. It turned out that this test revealed a few necessary modifications to make to the bends I put on the ends of my anodes and cathodes, so this was a very useful test. A surprise encounter between my thumb and the barrel of the soldering iron also made me painfully aware of just how difficult it is to solder the centrally located LEDs despite only being halfway done. But I persevered, determined to have a working cube by 2:00 AM. (It was about 10:30 PM at that point.)
A few minutes past 2:00 AM and my cube was structurally finished and completely wired with resistors and everything else necessary, looking like it does above. A half hour later I’d fixed a couple of solder joints that had snapped apart and was uploading my first test program to the Arduino. That first program, taken directly from the referenced guide, looked like this:
Proud of my handicraft, I then ziptied everything to the box my Arduino originally came in and set it out on the dining room table to show off. It wasn’t long until the novelty of a three-dimensionally rendered spinning helix began to wear thin and I began to notice just how ugly the whole setup looked. Realizing I have more prototyping boards than I can possibly use by the end of the (academic) year, I decided to dedicate some to this project, constructing my own shield for the Arduino Uno out of two additional proto-boards.
Having done away with the unsightly breadboard wires, I now had an easily removable and re-installable shield for my Uno.
This is the finished cube sitting atop the 'duino. Now that I was finally, truly done working, turned my eye towards finding some routines that were more visually stunning. This is one of them:
And as an added bonus, here's a picture of the early prototyping stages from when I was toying with the idea of hardwiring the cube to an Arduino Nano:
(Edited March 18, 2015: Added picture of cube attached to Arduino Nano board.)