With this 3-D printed "bionic skin" that can sense touch we're one step closer to true humanoids

In recent decades, the world has witnessed humanoid robots rapidly cross over from fantasy into real life. Now, engineers and scientists are one step closer to true humanoids with a 3-D-printed, skin-like fabric that can sense touch.

Scientists at the University of Minnesota essentially created sheets of bionic skin that may end up on robots or humans in the future. The flexible fabric, which can stretch as far as three times its normal size, is constructed in four layers laid down as “ink” from 3-D printers. First, scientists created a silicone base, then added two layers of electrodes that operate as pressure sensors. The last layer, which binds everything together, eventually was stripped away to keep the sensors exposed and sensitive to touch.

Artificial skin has captured the interest of scientists and engineers since the 1970s, who have long hoped to use it on burn victims or diabetes patients who suffer from severe skin ulceration. Interest in 3-D printing has been around for almost as long — 3-D printing was invented by Charles W. Hull in the mid-1980s — but this is the first time that both fields have come together in tandem with with sensors.

“I haven’t heard of anything like [this],” Robert Langer, a professor at the Massachusetts Institute of Technology who led research that developed a polymer-based layer of artificial skin in 2016, said in a phone interview. “The interesting thing is now you can have a smart skin, so to speak, right? This is all speculation, but maybe there could be a skin that can detect things in the environment.”

Most applications are left to the imagination for now, but the fabric’s sensors are sensitive enough to pick up on something as light as a human pulse. Scientists can’t yet print the fabric directly onto a human body, but the good news is that the inks from the 3-D printer already manage to set in a room-temperature environment. Normally, 3-D printing uses hot liquid plastic, which would make it impossible (and downright painful) to print onto human skin.

In the meantime, researchers have at least one other idea on how it can be used.

“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,” Michael McAlpine, the study’s lead researcher, said in a release. “The possibilities for the future are endless.”