Chinese researchers develop robot chameleon

Chinese researchers have developed a robot that can change color based on its background. With the camouflage technique, the researchers want to show how vehicles and armor can disappear into the background in the future.

The robot chameleon is made with a 3d printer, after which the robot is covered with plasmonic screens. The aim of the research is to develop a method that allows active camouflage to quickly adapt to its background. To achieve this goal, the researchers opted for plasmonic modulation. Plasmonic nanostructures of metal can be used to tune both optical reflection and absorption. As a result, the displays can change color when using the interaction between electric fields and nanostructures.

The researchers created the displays using a glass plate with a pattern of holes, each 50 nanometers apart. Gold was placed in these holes. Thereafter, the glass plate was placed in a housing of electrolytic gel containing silver ions. Changes in a local electric field cause the silver ions to stick to the gold surface, causing the screens to change color.

When light strikes the gold nanostructures, it produces plasmons that determine the reflection and absorption characteristics. When this happens, the screen appears red. If silver ions are then added with an electric field, this changes the properties and produces a different color.

The robot can detect the colors of its environment. Based on that, the electric field can be adjusted to get the desired color. At the moment, the robot chameleon is only able to produce the colors red, green and blue. The next step is to make all colors available. “This allows the robot chameleon to completely blend in with its environment,” said researcher Guoping Wang.