UTAKATA Is a Ticker-Like Bubble Display
This Arduino-based ephemeral device uses electrolysis to show scrolling characters on a liquid surface.
Researchers at Ochanomizu University in Tokyo, Japan have come up with a novel display method called UTAKATA that can create letters in flowing liquid. The ephemeral device uses seven electrodes to produce electrolysis in a water-based electrolytic solution of instant coffee, sodium bicarbonate, and cornstarch. These electrodes are arranged in a row to generate a line of floating “pixels,” which are pushed along by a water pump, making a sort of ticker tape effect.
The device is controlled on an Arduino Uno, which employs a number of MOSFETs to handle the current needed for electrolysis in the solution. As each electrode is activated, hydrogen bubbles form, floating to the surface and dissipating as they flow downstream. The array of electrodes act as cathodes here, while a common anode is inserted into the solution as well to complete the circuit.
UTAKATA was conceived of after previous experiments with a static 10x10 bubble display, which created bubble cluster images in under three seconds, but took 10 seconds to disappear. This flowing interface improves on that refresh rate significantly, and could be implemented to signify the ephemeral nature of life, and perhaps the actual message that's spelled out!
More details are available in the researchers’ paper, and you can see it demonstrated in the video below.