Dallas, TX – This week, KERA 90.1 is airing a series of reports: 'Engineering Hope: Groundbreaking Research That Could Change Our Lives'. In today's report KERA's BJ Austin visits a lab where researchers from North Texas universities are developing the next generation of prosthetic limbs for injured soldiers. It's cutting-edge research that could allow amputees to move more naturally and sense feeling with their artificial limbs.
In a busy Starbucks, two things make 28-year-old Clint Barkley stand out in the crowd: his clean cut good looks and his walk.
Barkley: We were just south of Fallujah in 2005. We ran over a land mine. I lost my left leg. Our gunner lost both of his feet below his knee.
The former Marine from Bedford walks unevenly, slightly stiff, but full of confidence. He wears a ten pound, titanium leg. It attaches mid-thigh and has a computerized knee.
Barkley: It reads your body weight, how you're moving and it reacts accordingly. I put my heel down then as I go and put all the pressure in my toe it knows I'm taking a step so it releases and kicks the foot back forward for me.
But what it doesn't do is allow a smooth, natural gait. And the leg does not allow him to feel the gravel in a driveway or the heat of an asphalt parking lot in August. But that could be in his future.
A consortium of scientists and engineers in North Texas and elsewhere are working on a way for the brain, the body's nerve impulses and an artificial limb to "talk" to each other. That could allow an amputee to "think" about moving an artificial arm or leg and the limb would respond immediately and more naturally. Conversely, the artificial limb would talk to the brain, giving it sensory input, thereby allowing the amputee to "feel". The research is being led by Marc Christensen, Professor of Engineering Innovation at Southern Methodist University. But, part of the project is taking place in a noisy, unassuming lab at the University of North Texas. That's where Christensen talked about the research, being funded initially by a 5.5 million dollar grant from the Department of Defense.
The idea is to put thousands of microscopic, silicon-like sensors on a single fiber - maybe as thin as a hair. Christensen says the combo of sensors and fiber optics would be implanted in the body and pass nerve signals to and from the artificial limb.
Christensen: We have incredibly sophisticated robotic arms. What we don't have is a perfect interface that when you think it, it does it. And when it feels something you experience it.
Christensen says there's a lot of similar research going on, but SMU has a secret weapon. It's Dr. Volkan Otugen, Chairman of Mechanical Engineering who has pioneered the microscopic sensors that connect to the optical fibers.
Otugen: They would sense the activity, nerve activity, nerve signal and transmit it to another location. From there it could also activate and create another light pulse to stimulate another part of the nerve. So it would be both sensing and stimulation. So, it's a two way communication between let's say the brain and a limb.
Dr. Otugen is making the super-tiny sensor "spheres" out of a spongy, silicon-like material that's almost like body tissue. And that's much better than the surgically implanted metal electrodes used in many other projects. They can damage tissue and can be rejected by the body's immune system. UNT's Dr. Guenter Gross, Professor of Biological Sciences, is testing the squishy-type materials and single cells for compatibility. He showed me how he monitors the neurons on computer screens.
Gross: The one on the front is really a bio-chemical test. This is now day 11.
Marc Christensen says this is extremely exciting work. And to think it started with a lunchtime discussion over Italian food, and diagrams on a napkin.
Christensen: This is a brand new idea that not anyone had really thought about more than a year or two ago. We're bringing together leading researchers in everything from photonics to packaging, to mechanical engineering to neuroscience trying to bring all of those pieces together to develop this new interface for the human nervous system. I think this is something where engineering and science can do good in the world. I think it is a very audacious, but very relevant goal.
Dr. Otugen cautions the research is in the very beginning stages. Right now, they're working with a bullfrog.
Otguen: He's in the biology department at SMU in the basement, and he's well-fed for now.
Human trials are at least a decade away.
Former Marine Corps Corporal Clint Barkley and his buddies can't wait.
Barkley: Any advance would be gigantic. It would be enormous for someone in my place.
Joining SMU and UNT in this research are the University of Texas at Dallas; Case Western Reserve in Cleveland, and Vanderbilt in Nashville.
The University of Texas at Arlington is doing related research under a Department of Defense grant.