Researchers from the University of South Australia, in conjunction with Australia’s Department of Defence, have developed a range of lightweight panels capable of changing color on demand. The panels use electrochromic polymers, which change color in response to an electric field. The colors may also be tuned to specific voltages.

The advance will allow drones to match the colors of their environment.

“Similar technology has been used in luxury cars, for dimming mirrors, and on the windows of the Boeing 787 Dreamliner,” said Kamil Zuber, research fellow at the University of South Australia. “But those applications are slow, require high power consumption to switch, and the electric flow must be maintained to sustain the change state.”

The new panels can change in a matter of seconds and offer color memory, meaning they can retain their switched color without a continuously applied voltage. The panels operate in the range of −1.5 to 1.5 V, meaning that they only need a AA battery to operate.

“We have built a small-scale frame of a UAV and put our panels on it. We have demonstrated it against all sorts of different sky states and completed a range of validation testing showing how these materials can respond to actual use,” Zuber said.

The panels come in about five or six different materials, each of which are capable of producing two to three different colors, he added.

“At this stage, we’ve been working mainly on the panels and the hardware, but during the latest stage of the project we’ve developed prototype electronics for the controller, which is something that could test the state of the sky and then automatically adjust the voltage to the panel to tune it to the right color,” Zuber said. “So if the UAV passed in front of a cloud, it would turn pale, then when it moved back into blue sky, it would turn back to blue.”