Robotic prosthetic ankles allow amputees more ‘natural’ and stable movement

Researchers at North Carolina State University (NC State) and the University of North Carolina at Chapel Hill built on previous work that found neural control of a powered prosthetic ankle can restore a range of abilities, including standing on challenging surfaces and squatting.

For this study, the researchers worked with five people who had amputations below the knee on one leg. Participants were fitted with a prototype robotic prosthetic ankle that responds to electromyographic (EMG) signals that are picked up by sensors on the leg.

Aaron Fleming, co-author of the study and recent Ph.D. graduate from NC State, said: “EMG sensors are placed over the muscles at the site of the amputation. When a study participant thinks about moving the amputated limb, this sends electrical signals through the residual muscle in the lower limb.

“The sensors pick these signals up through the skin and translate those signals into commands for the prosthetic device.”