To adequately mimic the function of a human hand and arm, a robotic prosthetic must interface with the wearer’s nervous system in a way that enables the wearer both to control the arm through brain commands and to receive sensory feedback from the limb. DARPA-funded research has now delivered on both of these requirements with recent tests demonstrating the successful efforts of researchers at the University of Pittsburgh and the University of Pittsburgh Medical Center to deliver sensory feedback directly to a test subject’s brain from sensors placed on the fingers of a robotic hand.
Breakthrough Builds on Earlier Brain Interface Success
Previous DARPA-funded research resulted in test subjects being able to successfully control the movement of a robotic arm and hand through a machine to brain interface. Both studies employed a robotic arm developed by the Applied Physics Laboratory (APL) at Johns Hopkins University.
In the most recent clinical trials, the subject, Nathan Copeland who suffers from quadriplegia, had tiny microelectrode arrays implanted in specific sites in the sensory and motor cortexes of his brain, those responsible for processing sensory information from the fingers and palm. These arrays were connected by wires to the prosthetic limb, enabling electrical signals originating in sensors on the robotic hand to travel directly to the brain where these signals were recognized by the subject with nearly 100% accuracy. As researchers applied pressure to each finger, Mr. Copeland, who was blindfolded for the test, was able to determine which finger was being touched and stated that he felt as if his own hand were being touched by the researchers.
Changing The Way Humans Interface with Machines
Justin Sanchez, Director of DARPA’s Biological Technologies Office and the program manager for Revolutionizing Prosthetics said of the research that, “This new capability fundamentally changes the relationship between humans and machines.”
The ultimate goal of DARPA’s Revolutionizing Prosthetics program is to develop technology that provides users of prosthetics with nearly natural control and sensation with their prosthetic limbs. Looking even further ahead, this research and the resulting technologies may one day re-define the relationship between humans and machines through seamless interfaces.
The findings of the University of Pittsburgh and University of Pittsburgh Medical Center team were published online in the journal Science Translational Medicine.
For further information on this research at DARPA’s website, visit http://www.darpa.mil/news-events/2016-10-13