Cricket ‘Hearing’ Sense Copied in Lab

Crickets are famous for making a racket disproportionate to their size. What has drawn many biologists to them, however, is their “hearing” -- or more precisely, how they use cerci, super-sensitive hairs on their back, to pinpoint minute shifts in air currents, such as the waft of an attacking wasp or spider.

Now, a team of physicists has recreated an admittedly crude facsimile of the insects’ efficient sensory system in the lab.

Attaching a few hundred thin plastic wires to sockets on silicon wafer sheets, the researchers developed “a prototype for technologies, such as hearing aids and sensors, that could help aerospace engineers visualize how air currents move across wings,” said Gijs Krijnen, a physicist who led the project with colleague Remco Wiegerink at the University of Twente in the Netherlands.

They describe their work in the current issue of the Journal of Micromechanics and Microengineering.

Like the crickets’ cerci, the wires are up to 1 millimeter long and are capable of rotating in response to air currents. That movement creates a tiny electrical impulse that is fed through the socket to a central computer.

Krijnen concedes that his team has yet to figure out how cricket neural networks are able to correlate data from cerci in time to help the insects hop safely away from predators. Thus, the physicists cannot mimic that process in their artificial system.

Still, Krijnen said, his device is already a viable prototype. “It can measure air pressure and particle velocity with much more precision and sensitivity” than existing technologies, he said.

Krijnen’s team created the artificial cricket hairs as part of CICADA, a European Union project aimed developing a life-like perception system.