U.K. researchers have developed a new kind of sonar inspired by dolphins. The sonar outperforms traditional sonar in bubbly waters, according to research forthcoming in the December 8 edition of the Proceedings of the Royal Society.
Clouds of underwater bubbles disrupt traditional sonar images, muddying the picture. Lead author Timothy Leighton recently explained the problem this way: “Cold War sonar was developed mainly for use in deep water where bubbles are not much of a problem, but many of today’s applications involve shallow waters.”
Leighton knew that dolphins hunted fish with “bubble nets,” however. “It occurred to me that either dolphins were blinding their sonar when making such nets, or else they have a better sonar system,” he says. “I sat down and worked out what pulse I would use if I were a dolphin.”
The solution he came up with was a kind of sonar that emits two pulses, one right after the other, one the inverted form of the other. He and his team tested the system first in a tank, and then in the Southampton waters, where marine traffic generates a lot of bubbles. In the wake of large ferries, the dolphin-inspired sonar outperformed traditional sonar.
Leighton envisions a range of potential applications, everything from harbor protection to improved ultrasound to the detection of improvised explosive devices.
Interestingly, though the invention was inspired by imagining how dolphins might use sonar, it remains unknown whether they do in fact use the type Leighton developed.