A prototype artificial skin that can mimic one of nature’s masters of camouflage, the squid, has been created by a group of researchers from Bristol University, advancing smart materials.
The team from the University’s Department of Engineering Mathematics said it has designed a smart materials system similar to natural chromatophores – cells largely responsible for the colour changes in squid and octopods’ skin that help the creatures elude predators.
The researchers created the artificial skin from electroactive dielectric elastomer – a soft material that can copy the action of biological chromatophores found on squid skin and can be electrically controlled. These pigmented cells work by expanding and contracting to change skin colour and texture instantly.
Aaron Fishman, visiting fellow in engineering mathematics, said: “Our ultimate goal is to create artificial skin that can mimic fast-acting active camouflage and be used for smart clothing such as cloaking suits and dynamic illuminated clothing.
“The cloaking suit could be used to blend into a variety of environments, such as in the wild. It could also be used for signalling purposes, for example search and rescue operations when people who are in danger need to stand out.”
The system uses simple local rules in the artificial chromatophore cells, so that they can sense their surroundings and manipulate their change. By programming the sets of cells in linear arrays, the engineers explored whether the system could produce multiple patterns.
The research, published in the Journal of the Royal Society publication 'Interface', found that the cells could mimic the complex patterning in real cephalopods – including the predator-diverting Passing Cloud display, where bands of colour spread as waves across the skin.
Five-to-ten millimetre thin sheets of dielectric elastomer were used in making bio-inspired artificial skin embedded with artificial chromatophores. The team is hoping to produce more patterns that could resemble the natural world.