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A D V A N C E D
M A T E R I A L S
&
P R O C E S S E S |
S E P T E M B E R
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designed a smart materials system, in-
spired by biological chromatophores,
which creates patterns that change and
morph over time and mimic biological
patterning. The artificial skin, made
of an electroactive dielectric elasto-
mer, can effectively copy the action
of biological chromatophores—small
pigmented cells embedded on a ceph-
alopod’s skin, which can expand and
contract and that work together to
change color and texture.
The system achieves the dynam-
ic pattern generation by using simple
local rules in the artificial chromato-
phore cells, so that they can sense
their surroundings and manipulate
their change. By modeling sets of arti-
ficial chromatophores in linear arrays
of cells, researchers explored whether
the system was capable of producing
a variety of patterns. They found that it
is possible to mimic complex dynamic
Three prototype artificial cephalopod chromatophores shown in unactuated states. Chro-
matophores are made of dielectric elastomer using tape coated with black carbon grease
electrodes. Courtesy of University of Bristol.
patterning seen in real cephalopods
such as the Passing Cloud display,
which is when bands of color spread as
waves across the skin. This visual effect
acts to distract and divert predators.