For this, we used a special material that responds to temperature changes.
A team of researchers from China has created tiny wings that can move faster than butterfly wings. As a source of energy, they use only sunlight. This is stated in a study published in the journal of the American Chemical Society.
According to the authors of the device, the design will allow tiny robots to fly without the need for additional power. Researchers added that using wings, you can even collect excess solar energy.
The miniature wings of Chinese scientists are a thin polymer sheet with a special metal film that responds to changes in temperature. When the sun shines on the strip, the wings bend, and the metal film expands more than the polymer layer.
After twisting, the metal falls into the shade, the temperature decreases and the wing unfolds. The two-stage process can be repeated at a speed of up to 4.5 times per second.
To demonstrate the work of the wings, the team created a mill and a tiny boat that used only the energy of the sun. In one of the demonstrations, they also showed a device that turns artificial light into electrical voltage.