The University of California at Riverside has developed a floating robotic film. The device already works autonomously and controls movements, and in the future it will be able to collect oil and purify water.

Initially, scientists wanted to create soft robots that would be self-sufficient and able to independently adapt to changes in the environment. They need sunlight to get energy, so they can work endlessly. In addition, these robotic films can be reused.

The robot was named Neusbot after neustons – animals that live on the border of water and air. This group includes water striders. These insects move along the surface of lakes and slow streams in pulsating movements. Neusbot was taught the same movements.

The prototypes of robotic films had been invented before: they could bend under the influence of light, but they could not create the controlled mechanical vibrations that Neusbot is capable of. And this movement is the key to controlling the robot to make it workable.

There are few ways to achieve this controlled movement with light. Scientists solved the problem with a three-layer film that works like a steam engine. The middle layer of the film is porous – it retains water and nanorods of iron and copper oxide. Nanorods convert light energy into heat, evaporating the water and providing pulsed motion across the surface of the water.

The bottom layer of Neusbot is hydrophobic, so even if the ocean wave sweeps over the film, it floats back to the surface. In addition, nanomaterials can withstand high salt concentrations without damage.

The direction of movement of the Neusbot can be controlled by changing the angle of the light source. That is, working only from the uniform light of the sun, the robot simply moves forward. And with an additional light source, you can tell Neusbot where to swim and what to clean.

Now the film robot has only three layers. But the research team wants to test other options, such as adding a fourth layer that can absorb oil or other chemicals. Usually ships are dispatched to oil spills for manual cleaning. Neusbot could work on tasks like a robot vacuum cleaner, but on the surface of water. Scientists also want to learn how to more accurately control the vibration mode and enable the robot to move in more complex patterns.