New camouflage technology has been developed that allows rapid changes in coloration based on sensing the environment. This new type of camouflage is based on an understanding of how biology works. Cephalopods, such as octopuses and squids, can change their skin coloration very quickly as they move among different environments. The newly developed electronically controlled camouflage technology works in a similar way.
Research was carried out at the University of Houston and the University of Illinois at Urbana/Champaign. John Rogers was one of the lead scientists who developed this new camouflage technology. The report on the research was published in the journal Proceedings of the National Academy of Sciences.
Cephalopods are able to change their coloration in milliseconds. They have cells in their skin called chromatophores that contain pigments that provide the color. Their skin also has cells that contain opsins that can receive light and determine the wavelengths of light from the environment that hit the skin’s surface. These cells exist in layers of the skin with the chromatophore layer on top, a muscle cell layer in the middle that moves the pigment cells, and the opsin cell layer on the bottom. Since color is dependent on the wavelengths of light, analyzing the composition of wavelengths of light hitting the skin allows for interpretation of the color in the environment. The cells in the skin of cephalopods can therefore continuously read the wavelengths coming from the environment and then alter the pigments in the chromophores to make the colors match. Cephalopods are capable of creating many colorful patterns in their skin.
The new camouflage technology works in a similar way to the camouflage mechanism in cephalopods but it can only change from black to white. It cannot produce reds, blues, greens or other colors. The technology is similar in that it both reads the state of the environment and then directs the changes in coloration accordingly. It therefore matches the pattern of the environment rather than the variation in hues.
The camouflage technology employs layers in a similar setup to that of cephalopods. The top layer has black pigment molecules that can turn transparent with heat. A middle layer consists of little reflective tiles that make the material appear white when the top is transparent. Another middle layer is made up of little motors, called actuators, that can produce heat if white in the environment is sensed. The bottom layer is the sensing layer that analyzes the environment using electrodes. These electrodes are only capable of sensing black or white, which means they only sense the amount of light reaching the electrode at that spot. The sheet with these layers is only about 200 microns thick and is very flexible.
The researchers who developed this technology have reported that they were tasked with studying how camouflage systems work in natural settings where there is an autonomous response to the surroundings. Their goal was to design a new camouflage method based on nature. They have reported that much more needs to be done to make this technology work successfully as a camouflage system in real life applications. One of the next developments that will be worked on is to add changes in color to the system.
By Margaret Lutze