At the University of Minnesota’s Characterization Facility and Polymer Characterization Facility, a new 3D printing material has been developed. This project, funded by the National Institute of Biomedical Imaging and Bioengineering of the National Institutes of Health, is detailed in the latest issue of the journal Advanced Materials.
This project was helmed by University of Minnesota Mechanical Engineering Associate Professor Michael McAlpine, who had previously “integrated electronics and novel 3D printed nanomaterials to create a ‘bionic ear’” in 2013.
Now, McAlpine and his team “have developed a revolutionary process for 3D printing stretchable electronic sensory devices that could give robots the ability to feel their environment. The discovery is also a major step forward in printing electronics on real human skin.”
As McAlpine explains, “this stretchable electronic fabric we developed has many uses. 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 using cameras like they do now. These sensors could also make it easier for other robots to walk and interact with their environment.”
Eventually, this wearable technology could “be used for health monitoring or by soldiers in the field to detect dangerous chemicals or explosives.” In order to create this material, the team developed a custom 3D printer. This multifunctional device “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.”
McAlpine went on: “while we haven’t printed on human skin yet, we were able to print on the curved surface of a model hand using our technique. We also interfaced a printed device with the skin and were surprised that the device was so sensitive it could detect your pulse in real time.”
The next step for this University of Minnesota team is “to move toward semiconductor inks [in order to print] on a real body.”
Image and Quotes Courtesy of the University of Minnesota