Autonomous underwater vehicles have become versatile tools for exploring the seas. But they can be disruptive to the environment.
Purdue University researchers are studying an alternative: highly manoeuvrable, low-cost underwater gliders that operate silently. Components and sensors of the glider also can be easily swapped out or added according to a wide range of mission specifications.
“Most underwater robots have limited battery life and must return back after just a few hours. For long-endurance operations, an underwater glider can travel for weeks or months between charges but could benefit from increased deployment opportunities in high-risk areas.” said Nina Mahmoudian, associate professor of mechanical engineering.
An underwater glider differs from other marine robots because it has no propeller or active propulsion system. It changes its own buoyancy to sink down and rise up, and to propel itself forward. Although this up-and-down approach enables very energy-efficient vehicles, it presents several problems: The vehicles are expensive, slow and not maneuverable, especially in shallow water. Shaped like a torpedo, the new glider solves these problems.
“It can operate in shallow seas and coastal areas, which is so important for biology or climate studies,” Mahmoudian said. “And because it’s totally quiet, it won’t disturb wildlife or disrupt water currents like motorized vehicles do.”