Penn State engineers have devised a circuit inspired by the way barn owls can so precisely determine where a sound is coming from and track their prey in the dark. Eventually, this fine example of biomimicry could lead to more accurate electronic navigation devices. Essentially, the owl's brain calculates the difference between when a sound arrives at the left ear compared to the right ear and uses that information to locate the source of the sound. After that is when things get interesting. From Penn State:
The speed of sound is faster than the owl's nerves can function so after the owl brain converts the sound to an electrical pulse, the pulse is slowed down. Then the brain's circuitry uses a lattice of nerves of different lengths with inputs from two ends, to determine which length is where the two signals coincide or arrive at the same time. This provides the direction.
Saptarshi Das and his team have created an electronic circuit that can slow down the input signals and determine the coincidence point, mimicking the working of the barn owl brain...
The team created a series of split-gate molybdenum sulfide transistors to mimic the coincidence nerve network in the owl's brain. Split-gate transistors only produce output when both sides of the gate match, so only the gate tuned to a specific length will register the sound. The biomimetic circuitry also uses a time-delay mechanism to slow down the signal...
"Millions of years of evolution in the animal kingdom have ensured that only the most efficient materials and structures have survived," said Sarbashis Das. "In effect, nature has done most of the work for us. All we have to do now is adapt these neurobiological architectures for our semiconductor devices."
"Barn owls may hold key to navigation and location" (Penn State)
