Camouflage has broad engineering and military applications. Most existing adaptive camouflage materials are limited by the need for additional stimulation or external sensors.

The researchers demonstrate the feasibility of using light-driven dynamic surface wrinkles for adaptive camouflage in a bilayer system inspired by the color-changing ability of cephalopods.

The authors used a polymer film to compose the rigid skin layer of the bilayer system. The soft substrate layer was composed of polydimethylsiloxane mixed with pigments that expand in response to certain wavelengths of light. The mismatch between the materials in the system in response to light resulted in the reversible formation of wrinkles.

In the wrinkled state, the system strongly scattered light and the pattern and color of the pigments were readily visible. In the smooth state, the pigmentation was no longer visible, leaving only the color of polydimethylsiloxane, which was chosen to match the background.

The authors adjusted the system to adaptively camouflage in response to various wavelengths, including sunlight under natural conditions. Because the system does not require sensors or additional stimuli, it provides an inexpensive and configurable approach to adaptive camouflage, according to the authors. 

https://www.pnas.org/content/118/48/e2114345118