Autonomous Robotic Sea Creatures Map, Monitor the Waters

Aquatic robots equipped with computer vision allow researchers to monitor marine biodiversity and habitats without disturbing the creatures they are observing. Eventually these devices can be used to map ocean floors and detect ships.

Image credit: National University of Singapore

Jacques Cousteau once said, “The sea, once it casts its spell, holds one in its net of wonder forever.” The mystery of the deep remains, and IoT technologies are helping researchers find new ways of discovering what lies below.

One window to the ocean comes from underwater autonomous vehicles, programmable robots that glide beneath the water. They can help researchers conduct experiments or take underwater images and measurements to monitor sea life and their habitats. They tend to look like mini submarines or missiles, but a new class of underwater vehicles is emerging, and it’s modeled after sea creatures themselves.

A Ray of Hope

Engineers at the National University of Singapore have developed the MantaDroid, a lightweight vehicle designed to help researchers study marine biodiversity and measure hydrographic data; it could conduct underwater surveillance in the future.

Like the real-life manta rays it mimics, the MantaDroid is flat to accommodate various sensors. Approximately one foot long and two feet wide, the MantaDroid weighs about 1.5 pounds. By flapping its flexible fins, the MantaDroid can travel 1.5 miles per hour for up to 10 hours, powered by a single motor on each fin and water propulsion. The team is still testing the MantaDroid to see how it performs in the open seas.

The MantaDroid won’t be the only robotic ray in the seas. Albayrak Savunma, a Turkish drone maker, teamed with researchers at Karadeniz Technical University to create the Wattozz, a stingray-shaped autonomous device designed for military use. Made of titanium and aluminum, the silicone-coated device has three integrated engines and cameras for eyes. It glides like a stingray underwater, traveling about 6.3 mph for up to 12 hours, and it is controlled using cryptographic acoustic sound waves. Typically used for observation, the stealthy Wattozz can carry explosives and attach itself to ships.

Fish Tales

Joining the stingray droids is SoFi, a soft robotic fish from the Computer Science and Artificial Intelligence Lab (CSAIL) at MIT. SoFi is designed to swim in three dimensions, so it can help researchers study aquatic life without disrupting it. SoFi has an on-board camera with a fisheye lens, of course. A soft robotic actuator and air pockets enable SoFi’s tail to move back and forth, mimicking the motion of real fish, but emitting less sound than a typical robot would.

Robot shaped like fish swims over ocean floor

Image credit: MIT CSAIL

The device is operated by a human diver with a remote control that communicates the speed, angle, and vertical dive maneuvers via sound waves. A control unit can change the air flow, enabling the robotic fish to dive or rise as it follows or mingles with other sea life. In tests, SoFi was able to collect data near coral reefs in the Pacific Ocean, while avoiding other marine life, and successfully operated 18 meters deep.

It’s possible that one day these robotic devices will be used with a docking station that sits in the water. Engineers at Purdue University are building a portable mobile docking station that would extend the time underwater vehicles can operate autonomously. Once docked, the vehicle can recharge their batteries and share data with researchers, without human intervention.

According to Nina Mahmoudian, an associate professor of mechanical engineering at Purdue, multiple docks could be strategically placed in the open water or adjacent to autonomous surface and underwater vehicles, to optimize the working life of each robot. She notes that the design is platform-agnostic, so the devices would determine when to dock, similar to the way a Roomba operates and recharges autonomously.