MIT Researchers Make Strides In Robotic Limbs

Imagine an artificial limb that responds to muscle movement and can bend at the knee or elbow almost as deftly as the real deal.

Researchers at the Massachusetts Institute of Technology did just that on rats, and the potential result is a breakthrough in the science of blurring the line between man and machine.

“Using biomechanical, electrophysiological, and histological evaluations, we demonstrate a viable architecture for bidirectional signaling with transected motor nerves,” team member Hugh Herr, a professor of media arts and sciences and a double amputee himself, said of the technique in the journal Science Robotics this week.

What Does That Even Mean?

What it means is that, for the first time, people will be able to feel and control robotic limbs through a method that physically attaches nerves and muscle to the prosthesis.

Currently, when a limb is amputated, people have no way of sensing the position of their artificial limbs.

“They have to visually follow their hands or their limbs, because there isn’t any feedback from the device or residual limb that tells their brain where their prosthetic limbs are in space,” Shriya Srinivasan, a graduate student and lead author on the paper, said on the school’s website.

The procedure was conducted on rats. Researchers severed muscles and nerves in the back right leg of seven rats, then grafted a pair of muscles from elsewhere on the animals and grafted on nerve endings.

When electrodes were attached, the muscles worked in tandem, one stretching while the other contracted.

Could Be Used On Humans In 2 Years

“This is fairly low-risk. It’s minor surgery,” Rickard Branemark, an orthopedic surgeon and prosthetics researcher at the University of California-San Francisco, told the journal Sciencemag.

With the new method and a smart prosthesis, “there’s every expectation that the human will feel position, will feel speed, will feel force in the same way that they once felt when they had a limb,” Herr, who lost his legs below the knees to frostbite while ice climbing, told the journal.

He said the procedure would be used on humans within two years.