Thanks to human behavior, the ocean is cluttered with pollutants like oil and contaminants from drinking water. These materials are harmful to the ecosystem, as they prevent vital oxygen from reaching marine life and are also toxic. Currently, to clean up oil spills, people are sent on ships to do this by hand using inefficient and dangerous methods. These include breaking the oil up into smaller droplets and dispersing it into the ocean, starting a fire at the surface to burn off the oil, and collecting it using skimmers.

A team from UC Riverside came up with a genius new idea to tackle this problem in a quicker, and less energy consuming, and polluting way. Their solution, published in Science Robotics, is an elegant robot that has the ability to independently collect pollutants, using a built-in layered film system.

“Our motivation was to make soft robots sustainable and able to adapt on their own to changes in the environment. If sunlight is used for power, this machine is sustainable, and won’t require additional energy sources,” said Zhiwei Li, a chemist at the institution. “The film is also re-usable.”

The device is named Neusbot, after the classification of animal neustons that can be found gliding along the water’s surface. Taking inspiration from these insects, the robot was designed to pulse along any body of water in a similar manner. Creating this flexible oscillatory movement in a robot is an engineering first, and key to its control and function.

“There aren’t many methods to achieve this controllable movement using light. We solved the problem with a tri-layer film that behaves like a steam engine,” Li explained. This film contains some iron oxide and copper nanorods, which act as a kind of vaporizer. It works by converting light into heat energy, allowing the robot to evaporate the surface water which powers the pulsating movement. Using light and water as an energy source makes the device renewable.

Scientists working on the project need to refine its movement and collection mechanisms before these gliding robots can be deployed, but this advancement in robotics is very exciting and much needed for the future of ocean conservation.

Source study: Science Robotics – Light-powered soft steam engines for self-adaptive oscillation and biomimetic swimming