Computing with Water
Over the years, some pretty weird items have been used to create simple computers, in the hope of finding a substance that will replace current computer hardware. Researchers have even suggested organic materials will one day replace computer motherboards (leaving me wondering if my next computer will be a machine or a pet).
Now researchers at Aatlo University in Finland have added another substance to the list of materials vying for a place in computer technology: water. And we’re not talking water with any special properties here; it’s the same type of water produced naturally or by water purification companies.
Previously, researchers used water to create “fluidic” computers, using continuous streams of air or water controlled with jets of fluid. In a Finnish study, however, water droplets were used to perform simple Boolean logic operations, the foundation upon which computing is based.
Superhydrophobic Droplet Logic
Superhydrophobic droplet logic sounds like a zany children’s show, but it actually describes the Finnish water computer quite accurately. To create the computer, researchers coated grooved copper plates with silver and applied a powerful fluorine-based water repellant. When tiny water droplets rolled down the plate grooves, they didn’t merge if they collided, but instead bounced apart like billiard balls.
Each droplet in the system acted as a little information packet of potable water, mimicking the action of information packets in real computers. The researchers were able to construct logic AND / OR gates using collisions between the droplets.
For instance, a flip-flop memory switch was created using a single groove that split into two separate grooves. One water droplet sat at the junction where the grooves split. When droplets ran down the single groove, they hit the stationary droplet and alternatively went down the right and left grooves. Researchers were able to alternate grooves without error for 100 droplets.
Okay, now for the inevitable question: so what? It’s a neat little trick, but perhaps isn’t ready for widespread consumer use. As one of the researchers himself noted, he was able to conduct “some of the early experiments on water-repellant plant leaves from my mother’s garden.” It’s not like we’ll be contacting water purification companies to repair our computers anytime soon.
The beauty of the system though, is that a water-droplet based computer, even a very simple one, runs without power. In other words, hydrophobic droplet logic could be used to control simple mechanisms in areas where power isn’t available, or where power supplies are unpredictable.
The researchers also note the water droplets could be used to deliver targeted chemical payloads by infusing each droplet with specific chemicals. This could have medical applications, as well as pave the way for chemical-based printing.
And besides, when all’s said and done, making a computer out of water is pretty cool.