Crickets spend most of their lives on the ground, making them vulnerable to wandering and flying predators. Species such as the wood cricket Nemobius sylvestris have developed a pair of hairy appendages at the abdominal end of their body called cerci, which are incredibly good at detecting small fluctuations in air currents the kind that might be caused by the beating of a wasp's wings or the jump of an attacking spider.
Each of the hairs on a cricket's cerci is lodged in a socket, which allows them to move in a preferred direction. Airflow causes a drag force on the hair, rotating its base and firing specific neural cells, which allows the cricket to pinpoint low-frequency sound from any given direction by using the combined neural information from all the sensory hairs on the cerci.
Physicists at the University of Twente in the Netherlands have now succeeded in building artificial sensory hair systems, which they hope will enable them to unravel the underlying process and develop sensor arrays with a variety of important applications.
The Twente team, led by Gijs Krijnen and Remco Wiegerink, have shown that they can make mechanical hair sensors and are able to fabricate them in large arrays of long hairs for the first time. They have also obtained experimental results, which reveal how good these artificial cricket hairs are at sensing low-frequency sound.
Contact: David Reid
Institute of Physics