Scientists Inch Along in Developing Snail-Bot to Tackle Ocean Plastic

Scientists have developed a robot prototype that may one day scoop up microplastics from the surfaces of oceans, seas and lakes. The robot’s design is based on the Hawaiian apple snail (Pomacea canaliculate), a common aquarium snail that uses the undulating motion of its foot to drive water surface flow and suck in floating food particles.

“We were inspired by how this snail collects food particles at the [water and air] interface to engineer a device that could possibly collect microplastics in the ocean or at a water body’s surface.”

Sunghwan “Sunny” Jung, professor in the department of biological and environmental engineering at Cornell University

Currently, plastic collection devices mostly rely on drag nets or conveyor belts to gather and remove larger plastic debris from water, but they lack the fine scale required for retrieving microplastics. These tiny particles of plastic can be ingested by marine animals, thereby entering the food chain where they become a health issue and potentially carcinogenic to humans.

The prototype, modified from an existing design, would need to be scaled up to be practical in a real-world setting. The researchers used a 3D printer to make a flexible carpet-like sheet capable of undulating. A helical structure on the underside of the sheet rotates like a corkscrew to cause the carpet to undulate and create a travelling wave on the water, sucking in microplastics.

“We needed to understand the fluid flow to characterize the pumping behavior,” Jung said. The fluid-pumping system based on the snail’s technique is open to the air. The researchers calculated that a similar closed system, where the pump is enclosed, would require high energy inputs to operate. On the other hand, the snail-like open system is far more efficient, running on only 5 volts of electricity.

Due to the weight of a battery and motor, the researchers may need to attach a floatation device to the robot to keep it from sinking, Jung said. While the microplastic-cleaning robot is still in early stages, the researchers hope their slow but steady progress will someday make a dent in the growing plastic pollution problem facing our oceans.

The study was funded by the National Science Foundation and you can read the full paper in Nature at this link.

Staff Writer

Our in-house science writing team has prepared this content specifically for Lab Horizons

Leave a Reply

Your email address will not be published. Required fields are marked *