Experimental prosthetic arm allows amputees to 'feel' again
A longtime amputee was able to pluck grapes without crushing them, pick up an egg without cracking it, and put on his wedding ring thanks to a new prosthetic hand that allows its wearers to artificially “feel” again.
Real estate agent Keven Walgamott lost his left hand and a portion of his arm during an electrical accident in 2002. Since his amputation, Walgamott has been unable to feel anything in that limb.
That is, until he was fitted with an experimental prosthetic arm for the first time in 2017 that can be directed by the user’s thoughts.
“It almost put me to tears,” Walgamott said in a press release on Wednesday. “It was really amazing. I never thought I would be able to feel in that hand again.”
Inspired by Star Wars hero Luke Skywalker’s robotic hand in the film “The Empire Strikes Back,” the new-and-improved “LUKE arm” was developed by researchers from the University of Utah in collaboration with the University of Chicago and the Cleveland Clinic.
The enhanced prosthetic mimics the way a human hand feels objects by sending signals back to the brain, according to the researchers.
“We changed the way we are sending that information to the brain so that it matches the human body. And by matching the human body, we were able to see improved benefits,” the project’s lead author Jacob George said in the release.
In order to allow the wearer to sense if something is soft or hard and how to pick it up, the researchers developed a system that allows the prosthetic to “tap into” the user’s nerves through a bundle of 100 microelectrodes and wires that are implanted into the amputee’s forearm and connected to an external computer. The computer then translates these signals to direct the arm to move.
“What we're doing is trying to communicate with the body in the body's natural language and by doing that we saw enhanced benefits with sensory feedback,” George told local station KTVX on Wednesday.
To replicate a sense of touch for the user, the research team outfitted the robotic hand with sensors that send signals to the remaining nerves to mimic the feeling of holding an object.
“We’re not quite there yet, but the sense of touch and the sense of movement that we're able to recreate does seem very real, though not quite as rich as what the biological realities are,” Gregory Clark, a biomedical engineering associate professor at the University of Utah, explained to local station KTVX on Wednesday.
While the current prototype can only work while connected to a computer outside the body, the developers said they hope to create a portable version that would be completely wireless.
The research team said they’re hoping to have the prosthetic arm ready for test subjects’ to take home by 2020 or 2021, pending regulatory approval by the U.S. Food and Drug Administration.
The academics’ findings have been published in the journal Science Robotics.