Potential Key to Prosthetics That Feel

Over the past dozen years advances in prosthetics have enabled some troops who have lost use of a hand or lower part of a leg to continue to serve; some airborne soldiers have retained their jump status because of strong and sophisticated prosthetics.

But touch, feeling something coming into contact with the prosthesis, is something no one has regained – yet.

That soon could change with the development of an ultra-thin, featherweight electronic sensor foil that can be shaped or molded to any surface. The technology builds on other recent breakthroughs, including a flexible electronic circuit developed at the University of Illinois, Urbana-Champaign, that monitors body movements when applied to the skin.

At the University of Tokyo, engineer Martin Kaltenbrunner is taking that technology to another level by developing bendable circuits than can be applied over large areas. The touch sensor foil Kaltenbrunner is developing is 2 micrometers thick (the width of a strand of spider web silk is anywhere from 3 to 8 micrometers) and is 27 times lighter than a sheet of office paper, according to Kaltenbrunner.

They are extremely flexible and can be crumpled like a tissue or conform to any object, he said, allowing them to be used in a variety of applications healthcare, mobile appliances and even in architecture and design. And that includes being applied to prosthetic limbs, effectively giving wearers a sense of feeling.

“I would definitely say that our technology can be of use to treat wounded or injured, as the main focus of our research lies on medical devices,” Kaltenbrunner said in an email to Defense Tech. “Artificial limbs or prosthetics could most certainly be equipped with our ultra thin sensor sheets, but I can imagine them as well to be worn by patients for post-operative monitoring and treatment.”

The hope, he said, is that extremely thin, flexible e-skins can be used as a way to monitor a patient’s heart, blood pressure, body temperature and more, or to place it near the site of a surgery or wound for post-operation follow-ups.

“The basic idea is to have a form of ‘smart’, unobtrusive batches that can tell the patient or the doctor more about his physical situation and the process of healing,” he said.

Kaltenbrunner said he has not had any inquiries from the Department of Defense about the e-skin.

“I can imagine they would be interested in our research,” he said. “However, as far as I know, the University of Tokyo is not allowed to conduct military-funded research, so this might be a little complicated here. But I would believe that any research aimed at patient treatment will be fine.”

About the Author

Bryant Jordan
Bryant Jordan is a reporter for Military.com. He can be reached at bryant.jordan@military.com. Follow him on Twitter at @BryantJordan.
  • LtKitty

    God, it’s this sort of innovation and development that really gets my heart pumping. I hope they can turn this research into a practical product instead of it getting lost in “what could have been” technologies.

  • hibeam

    You should show a picture of a drone. Drones are the key to our people getting injured in the first place.

  • blight_

    From a robot of the future: “I know now why you cry”


    Can we take a moment now to respect the men and women that serve in our military; and realize how helpful this technology is? I know that respect and courtesy isn’t something you see here on this site, but honestly, our soldiers might be able to live normal lives; lets respect that.

  • blight_

    I’d be more excited at the idea of materials that can conduct sensation from the surface into the PNS/CNS. There’s always the possibility of implantable materials that would do motor someday, and enable the paralyzed to walk again.

  • Dfens

    I notice it is ribbed. I thought that was for her pleasure.

  • Rob C.

    This great news, not only for injured soldiers coming home from the battlefield, but also people in general who are crippled. I hope this technology is able fully developed soon and its costs kept down accessible levels for all. Good News!

  • hibeam

    We can transplant limbs now. Stop with the silly cyborg stuff. Waste of time and money.