Researchers develop artificial skin capable of detecting temperature changes

Using similar biological mechanisms to those that allow snakes to sense prey through heat, engineers and scientists at California Institute of Technology (Caltech) and ETH Zurich have developed an artificial skin that's capable of detecting changes in temperature.

Published Feb. 1 in Science Robotics, the paper details the materials development from synthetic wood in a petri dish to temperature sensitive skin. Led by Caltech's Chiara Daraio, researchers used the long-chain pectin molecule found in plant cell walls to give the skin its temperature-sensing capabilities.

"Pectin is widely used in the food industry as a jellifying agent; it's what you use to make jam. So it's easy to obtain and also very cheap," said Daraio, a professor at Caltech.

Currently, electronic skins are able to sense temperature changes of less than a tenth of a degree Celsius across a five-degree temperature range. The new skin has a sensitivity rate an order of magnitude smaller and has a responsivity that is two orders of magnitude larger than current methods. By detecting changes between five to 50 degrees Celsius (41 to 158 degrees Fahrenheit), the skin makes for a more human feel when used in robotics and biomedical products.

Researchers hope that this skin could cover prosthetics to restore temperature sensing to amputees or be used as a bandage to sense the increase in temperature on a wound developing an infection. Daraio’s team is currently working to increase the range to 90 degrees Celsius (194 degrees Fahrenheit) to make the sensors useful in consumer electronics or robotic skins.