Ferrofluids are liquids that react to a magnetic field, and a group of students at the University of Oslo — going by the moniker ‘Applied Procrastination’ — have decided to create a display with this substance. They’re calling the resulting 252-pixel monster, ‘Fetch,’ and they’re documenting the build process starting with the video seen below.
While the large display is still something of a mystery, initial freeform and electromagnet experiments appear to be amazing. In fact, as the black ferrofluid flows and pools in its thin tank, it looks something like an exotic sea creature. The culmination of this video is a 6x6 electromagnet prototype, which attracts dots of fluid to each in a square pattern. Closer packing of the cylindrical electromagnets used here is possible, but they found that further collapsing things complicated the project too much.
Even so, the electronics needed to drive the prototype display’s 36 magnets turned out to be massive, though they were eventually able to simplify things by using surface-mountable ULN2004 motor drivers. The project is controlled using an Arduino board, and while some of the details are still a mystery, the visual results shown so far are stunning. One would imagine the full-scale design will be incredible, though you’ll need to subscribe to their channel or check back later to see what happens!