Logic Gate Study Analyzes Crab-Inspired Computing
April 16, 2012

Logic Gate Study Analyzes Crab-Inspired Computing

A team of scientists from Japan and the UK have built a computer that is inspired by a most unusual source -- the real-life movements and swarming behavior of soldier crabs, PCMag.com's David Murphy and Wired UK's Olivia Solon reported over the weekend.

The researchers, who are affiliated with Kobe University and the University of the West of England (UWE), devised the system for defining computer logic based on the crabs' movements and their "natural tendency for swarming," which according to Murphy "can be exploited in a maze-like environment to serve as living representations of AND, OR, or NOT functions."

"When a swarm of soldier crabs is set in a corridor, it is expected that a swarm acts as a robust ball and goes straight, and that two swarm balls are united into one ball after colliding," authors Yukio-Pegio Gunji, Yuta Nishiyama, and Andrew Adamatzky wrote in their study, 'Robust Soldier Crab Ball Gate,'. "Because of velocity matching, a swarm ball resulting from the fusion of two balls has a summary velocity of two colliding balls."

Essentially, what they did was construct a series of gates featuring a pair of walled tunnels which came together into another, lone walled tunnel, he added. The soldier crabs were placed into each of the tunnels, where they obeyed their natural instincts and followed the walls to the point where the two tunnels merged into one. Once they met, the two groups of crabs would combine together into a single swarm and continue down the single tunnel, and their actions essentially recreate an "OR" function, PCMag.com said.

However, Solon said, when the scientists tried to sent their teams of 40 crabs through a path representing an "AND" gate -- that it, a place where the combined crab swarm is set to head down one of three different tunnels -- the results were "less reliable," with the crabs not performing well when it came to choosing the primary "AND" gate and ignoring the other two tunnels in the process. That said, the researchers told Wired that they believe that they can improve the results by making the environment more "crab-friendly."

The Kobe University and UWE study builds upon an idea that originated back in the early 1980s, according to a report published by the MIT Technology Review. The theory, which was first put forth by computer scientists Ed Fredkin and Tommaso Toffoli, analyzed how it could be possible to build a computer out of billiard balls.

"The idea," according to that article, "is that a channel would carry information encoded in the form of the presence or absence of billiard balls. This information is processed through gates in which the billiard balls either collide and emerge in a direction that is the result of the ballistics of the collision, or don't collide and emerge with the same velocities."

Image Courtesy Peter Ellis/Wikipedia (CC BY-SA 3.0)