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Flow sensors based on hair structures of cavefish

Although members of the fish species Astyanax fasciatus cannot see, they sense their environment and the movement of water around them with gel-covered hairs that extend from their bodies. Their ability to detect underwater objects and navigate through their lightless environment inspired a group of researchers to mimic the hairs of these blind cavefish in the laboratory.

While the fish use these hairs to detect obstacles, avoid predators and localize prey, researchers believe the engineered sensors they are developing could have a variety of underwater applications, such as port security, surveillance, early tsunami detection, autonomous oil rig inspection, autonomous underwater vehicle navigation, and marine research.

Vladimir Tsukruk and graduate students Michael McConney and Kyle Anderson conducted preliminary experiments with a simple artificial hair cell microsensor made of SU-8, a common epoxy-based polymer capable of solidifying, and built with conventional CMOS microfabrication technology. They found that the cell by itself could not achieve the high sensitivity or long-range detection of hydrodynamic disturbances created by moving or stationary bodies in a flow field. The hair cell needed the gel-like capsule, called the cupula, to overcome these challenges.

“After covering the hair cell with synthetic cupula, our bio-inspired microsensor had the ability to detect flow better than the blind fish. The fish can detect flow slower than 100 micrometers per second, but our system demonstrated flow detection of several micrometers per second,” said Tsukruk.

Source: gtresearchnews.gatech.eduAdded: 15 September 2009