The "skin" includes a sensor as well as two layers of transparent film that is based on a carbon nanotube structure that is "airbrushed" onto silicone.
According to the researchers, "nanobundles" align themselves into the direction the silicone is stretched. When released, the structure retreats to its original dimension and the nanotubes create "spring-like" structures that enable repeated stretching without deforming the material. The scientists described their discovery as an "artificial super-skin".
The two-layer structure acts as a sensor that can maintain conductivity in both the stretched and unstretched states, enabling it to "detect and measure the force being applied to them through these spring-like nanostructures, which serve as electrodes," the researchers said.
The middle silicone layer is used to store electricity, similar to a battery: "When pressure is exerted on the sensor, the middle layer of silicone compresses, which alters the amount of electrical charge it can store. That change is detected by the two films of carbon nanotubes, which act like the positive and negative terminals on a typical automobile or flashlight battery."
This effect could allow researchers to extract a sense of "feeling" and even locate it directly at pressure points where deformation happens. So far, the team says it has not spent much time on "optimizing" the sensitivity of the sensor. However, they did not express concern that this will be a significant hurdle either.