Engineering researchers at the University of Minnesota have created a 3D-printed bionic skin, potentially creating a way for robots to feel like humans do. Based on stretchable electronic sensory devices also make it easier for other robots to walk and interact with their environment.

This revolutionary 3D-printing process is a major step forward in printing electronics on the real human skin, developed for endless possible applications, from surgical robots to wearables that can detect explosives.

A new 3D-printed bionic skin could soon allow robots to feel the world around them. Researchers say it’s a step toward electronic devices that can be printed directly onto the human body. Image credit: Shuang-Zhuang Guo and Michael McAlpine, University of Minnesota

How Does It Work?

Researchers made the unique sensing fabric with a one-of-a-kind 3D printer they built in the lab. The multifunctional printer has four nozzles to print the various specialized “inks” that make up the layers of the device—a base layer of silicone, top and bottom electrodes made of a conducting ink, a coil-shaped pressure sensor, and a sacrificial layer that holds the top layer in place while it sets. The supporting sacrificial layer is later washed away in the final manufacturing process.

Unlike conventional 3D-printing systems, which use hot, rigid liquid plastic, these layers of ‘ink’ set at room temperature – meaning it could be printed directly onto human skin. The end product is a flexible fabric of electronic sensors that can stretch up to three times their original size.

Michael McAlpine, the lead author of the study and a mechanical engineer at the University of Minnesota, explains: This is a completely new way to approach 3D printing of electronics. Putting this type of bionic skin on surgical robots would give surgeons the ability to actually feel during minimally invasive surgeries, which would make surgery easier instead of just use cameras like they do now.

According to the team’s papers, this technique also makes it much easier to transition to practical use, as the manufacturing is built right into the process. 3D-printed bionic skin offers infinite possibilities for the future – from health monitoring to energy harvesting to chemical sensing. Since researchers haven’t printed on human skin yet, their next step is to move toward semiconductor inks and printing on a real body.