By Erin DostalThe Daily Northwestern
Since the 2003 start of the Iraq war, more than 500 U.S. soldiers have arrived home missing arms and legs, prompting the Defense Advanced Research Projects Agency to provide $48.5 million to companies and schools for research and development in prosthetics. Northwestern is one of the 30 institutions taking part in the initiative.
The initiative officially began in early 2006, but proposals were started in 2005, said Feinberg Prof. Richard Weir, a project investigator.
“There’s a disproportionate number of casualties coming back from Iraq who have had amputations due to the fact that they wear body armor,” Weir said. “It tends to keep you alive but the only thing sticking out of the body armor are your hands and legs.”
Weir’s team of researchers is designing the physical hardware for prosthetic hands and for an arm system. The current initiative does not involve research into prosthetic legs, Weir said.
NU researchers are working closely with the Austrian branch of Otto Bock – a leading maker of prosthetics – on two prototypes, Weir said. The first prototype is made up of a shoulder, a humeral rotator and a wrist flexion unit.
The second prototype is something called an “intrinsic hand,” a prosthetic hand that has all the motors and electronics that move the prosthetic located within the fingers and the palm, Weir said.
Another team of NU researchers, headed by McCormick Profs. Ed Colgate and Michael Peshkin, is building an extrinsic hand with the motors and electronics located in the forearm.
Researchers are also hoping to make use of “implantable sensors,” which would detect muscular activity in the body and would be used to provide greater control and freedom of movement to the user, Weir said.
NU was already working on research for implantable sensors when the initiative began. The first project was sponsored by the National Institutes of Health, and additional funding fueled the process, Weir said.
The new initiatives are very different from the existing technologies available to amputees. Most current prosthetic arm systems include only an elbow, a rotator and a hand. This allows the user about one degree of freedom per joint, which Weir said isn’t much.
“This project is full-armed with a hand that has all the articulations in it,” he said. “You have 22 degrees of freedom in your hand and arm, and this project seeks to replicate those.”
This is a huge jump for what prosthetic arms are capable of, Weir said, adding that the initiatives are also hoping to create better prosthetic arm control for patients.
“We’re essentially doing the mechanical design for all these systems – getting them fabricated and tested, and trying to make them all work,” he said.
Reach Erin Dostal at [email protected].
