The solder of the future may be able to sneak into enemy-held locations and evade opposing forces by wearing disposable stick-on camo – based on squid biology – that renders them undetectable to night vision-enabling infrared cameras and sensors.
Although not yet ready for use, the technology has been presented by its inventors from the University of California at Irvine, who believe it has considerable potential for use in the field.
“Soldiers wear uniforms with the familiar green and brown camouflage patterns to blend into foliage during the day, but under low light and at night, they’re still vulnerable to infrared detection,” said lead researcher Dr Alon Gorodetsky.
“We’ve developed stickers for use as a thin, flexible layer of camo with the potential to take on a pattern that will better match the soldiers’ infrared reflectance to their background and hide them from active infrared visualization.”
With an appearance and texture similar to sticky tape, but coated with a reflective protein, the camo is designed to stick to the fabric camp uniforms of soldiers.
Known as “invisibility stickers”, they would be worn only when needed, and are designed to quickly be added or removed as required: the team envision soldiers carrying a roll of the camo with their kit, ready to be used at a moment’s notice.
Although not the most sophisticated solution to camouflage, the stickers are designed to be very cheap to produce, making them an appealing way for cash-strapped militaries to provide ground troops with infrared-proof camouflage.
“We’re going after something that’s inexpensive and completely disposable,” added Gorodetsky. “You take out this protein-coated tape, you use it quickly to make an appropriate camouflage pattern on the fly, then you take it off and throw it away.”
The protein coating the infrared-resistant surface is known as reflectin, and is also found in the camouflage-inducing cells of squid, called iridocytes.
The researchers saw squid biology as key to producing the infrared-resistance capabilities, and were able to identify the reflectin and reproduce it using bacteria.
However, finding a workable way to trigger the light-reflecting properties of reflectin on the camo has been more challenging.
The researchers first tried exposing the film to acetic acid vapors, which works in that it makes the film invisible to infrared cameras but would be a nightmare in the field.
“What we were doing was the equivalent of bathing the film in acetic acid vapors – essentially exposing it to concentrated vinegar,” said Gorodetsky. “That is not practical for real-life use.”
Now the researchers are working on a solution that stretches the material to make it infrared-proof, and also allows multiple stickers to respond in unison.
However, the team believe that the stickers could also be used to trap or release body heat in clothes if re-tuned to a different infrared wavelength, meaning this squid-inspired technology could form the climate-adapting clothing of tomorrow.