It took four decades for Fred Downs to be able to pinch himself with his left hand. Or open a jar. Or turn a key in the front door of his Virginia home.
Downs now sports a new prosthetic arm funded by the Defense Advanced Research Projects Agency (DARPA), and which only last week received Food and Drug Agency approval for commercial use.
Downs’ arm, with movable fingers and wrist that let him grasp and pinch, replaces the metal hook he had since losing his arm during the Vietnam War 46 years ago. The program concept began in 2006 and DEKA Research and Development Corporation brought the concept to reality. For Downs’ prosthetic, he controls every movement via sensors strapped to his shoes. The system of sensors and wireless signals lets wearers simultaneously control multiple joints and perform varying movements of wrist and fingers, says Justin Sanchez, program manager for DARPA’s Revolutionizing Prosthetics program under the Biological Technologies Office.
The size, shape and weight of the prosthetic are as close to human as possible, allowing for users to get used to and adapt much quicker to the arms. “If it feels natural, that’s a good thing,” Sanchez says.
Researchers too have developed a system in which quadriplegics can control artificial limbs via wireless sensors using an interface of microchips implanted on the surface of the brain. “They just think it and it moves,” Sanchez says.