Chameleon-Inspired Robot Uses Thermochromic Camouflage to Turn Its Skin Into a Flexible Display

Researchers from Seoul National University and Hanyang University have unveiled a soft robot capable of altering its coloration using thermochromic patterns — inspired by chameleons and their color-shifting skin.

"Development of an artificial camouflage at a complete device level remains a vastly challenging task, especially under the aim of achieving more advanced and natural camouflage characteristics via high-resolution camouflage patterns," the team explains of the problem to be resolved. "Our strategy is to integrate a thermochromic liquid crystal layer with the vertically stacked, patterned silver nanowire heaters in a multilayer structure to overcome the limitations of the conventional lateral pixelated scheme through the superposition of the heater-induced temperature profiles."

In short: The team has created a robot that's able to sense the colors surrounding it and automatically change its patterning to match, near-instantly — taking as its inspiration the chameleon, though powered by an Arduino Mega 2560 board and AMS TCS3472 color sensors rather than nature.

"At the same time, the weaknesses of thermochromic camouflage schemes are resolved in this study by utilizing the temperature-dependent resistance of the silver nanowire network as the process variable of the active control system," the paper's abstract explains. "Combined with the active control system and sensing units, the complete device chameleon model successfully retrieves the local background color and matches its surface color instantaneously with natural transition characteristics to be a competent option for a next-generation artificial camouflage."

"This chameleon skin, the surface, basically is a kind of display," Seung Hwan Ko, Seoul University professor and co-author of the paper, tells MIT Technology Review of the work. "It can be used for a soft or stretchable or flexible display."

The team's work has been published under open-access terms in the journal Nature Communications.