Spray-On Antennas and Skin Could Transform IoT and Robotics for Manufacturing

A pair of new spray-on technologies could help engineers and plant managers increase performance in their factories.

The first is a spray-on antenna. Researchers at Drexel University’s College of Engineering have created a method for spraying invisibly thin antennas, made from a two-dimensional metallic material called MXene, that function on the same level as the antennas in today’s mobile devices and routers.

MXene is a titanium carbide that can be dissolved in water to create an ink or paint. Its exceptional conductivity enables it to transmit and direct radio waves—even in coats that are mere tens of nanometers thick. It would allow antennas to be embedded in—or sprayed on—a variety of objects and surfaces without adding much weight or circuitry. The surface doesn’t have to be rigid either.

MXene “Antenna Spray Paint.”

"The ability to spray an antenna on a flexible substrate or make it optically transparent means that we could have a lot of new places to set up networks,” said Kapil Dandekar, a professor of electrical and computer engineering at Drexel. “This technology could enable the truly seamless integration of antennas with everyday objects which will be critical for the emerging Internet of Things."

The other interesting breakthrough is an electronic skin that can be applied in a sprayable solution to robotic parts. Developed by a team from the Korea Advanced Institute of Science and Technology research team, the technology is a stretchable skin-like tactile sensor that can be sprayed on irregular-shaped objects such as robot parts.

The structure of the skin was designed to respond differently to strain than to pressure. Under applied strain, conducting pathways adapt to change the material’s resistance. Under pressure, on the other hand, there is little change in response, rendering the skin non-responsive to pressure.

The research team also used electrical impedance tomography (EIT)—a type of medical imaging that uses low-frequency electrical current to probe a body and is sensitive to changes in electrical conductivity—to map the strain. By using EIT, it is possible to minimize the number of electrodes needed, increase durability, and enable easy application onto three-dimensional surfaces.

"Our electronic skin can be mass produced at a low cost and can easily be coated onto complex three-dimensional surfaces,” said Professor Steve Park, co-lead of the research team. “It is a key technology that can bring us closer to the commercialization of electronic skin for various applications in the near future."

Sprayable Tactile Sensors for Robots.

The ability to give almost any object an antenna, and almost any robot a touch-sensitive skin, promises to open many possibilities for manufacturers to better interconnect their assets—and make them more responsive to manufacturing needs.

Read more about integrating electronics into complex materials at Bend, Flex, and Twist: Flexible Electronics Are Coming.