It may smell amazing, but that fresh cut Christmas tree in your living room can be a genuine fire hazard if you don’t regularly water it. But a dried tree engulfed in an inferno of flames almost seems safe next to this digital Christmas tree that spins a strip of flashing LEDs at terrifying speeds to create a neat holographic effect.
It’s another creation from hardware hacker Sean Hodgins, who always seems especially inspired around the holidays. In years past, Hodgins has created tiny TV ornaments that actually play retro holiday commercials, but this year, he stepped up the complexity considerably, with a tree that’s easy to decorate and even easier to store the rest of the year. Unfortunately, it’s also really scary and was prone to breaking during the build.
Through some trial and error that involved failed bearings, an overly shaky support frame, and a burned out motor that had to be replaced with a half-horsepower electric AC motor, Hodgins eventually got the “tree’s” simple triangular metal frame to spin at speeds that allowed the persistence of vision effect to work properly. But the wind resistance of the square metal tubing used to build the tree meant the whole thing had to be shortened to just five feet tall for the motor to have enough power to spin it fast enough.
A Raspberry Pi is used to power the strip of LEDs, which flash to produce images based on input from a static hall effect sensor detecting a magnet attached to the top of the spinning tree. Animations are created by filling a folder with sequential still images, and while the resolution of the strip of LEDs is relatively low, the pixelated effect of the decorated tree is a big part of the charm. It definitely looks hacked together, and the safest way to huddle around it to sing Christmas carols is behind a sheet of bulletproof glass, but at least you don’t have to drag it to the curb when New Year’s rolls around.