After Utopia Festival last year, Bob made a very sensible observation about the Disco Robots. The moving ear-antennae looked great, but once the smoke and haze got going they had a tendency to disappear. So naturally, in my mind, the solution was obvious: just add more LEDs. The problem was working out how to do that without making the robots look garish or disturbing the overall aesthetic. I didn't want to simply stick a strip of LEDs onto the side of their heads and call it finished, so it took me ages to formulate an idea that I actually liked.
It then took considerably longer to translate that idea into something I could physically build. There were quite a few 3D prints that ended with me looking at them and muttering, “Bloody idiot, of course that won't work,” mixed in with plenty of, “Yes, that works... but if I just did this, it would be even better.” And, inevitably, an added sprinkle of, “Remind me again, why did I decide to do this?” Eventually, though, the new ear lighting fixture started to become an actual thing rather than an embarrassingly large amount of 3D printing waste.
Along the way I made one particularly interesting discovery. I'd been printing the diffusers in transparent PETG, using the word transparent fairly generously because FDM 3D printing isn't exactly famous for producing optically perfect transparent objects. In this case, however, the imperfections turned out to be useful. The layer lines in the printed PETG scatter the light perpendicular to the direction of the layers, so instead of simply seeing a matrix of individual LEDs through the diffuser, the light stretches into a series of bright vertical lines.
The result is rather lovely. What should technically be an imperfection in the manufacturing process turns the LED matrix into something that looks almost electrical: a row of glowing vertical bars running through the ear fixture. It wasn't an effect I'd designed deliberately, but having discovered it, I'm very definitely keeping it. The fixtures are now at the testing stage and, for once, the answer really was: just add more LEDs.