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'60 Minutes' video: The Pentagon's bionic arm

In all the wonders of modern medicine, building a robotic arm with a fully functioning hand has not been remotely possible. But that is starting to change.

When Americans are wounded in Afghanistan or Iraq, no expense is spared to save their lives. But once they're home, if they have suffered an amputation of their arm, they usually end up wearing an artificial limb that hasn't changed much since World War II.

In all the wonders of modern medicine, building a robotic arm with a fully functioning hand has not been remotely possible.

But as 60 Minutes correspondent Scott Pelley reports, that is starting to change. One remarkable leap in technology is called the DEKA arm and it's just one of the breakthroughs in a $100 million Pentagon program called "Revolutionizing Prosthetics."

Fred Downs has been wearing the standard prosthetic arm since 1968, after he stepped on a landmine in Vietnam.

"It's a basic hook. And I can rotate the hook like this and lock it," Downs told Pelley, demonstrating the limited movement ability of his prosthetic arm. "In those days they didn't have a lot of sophistication about it. They fit you and say, 'This is your arm, this is your leg.' And it was the best technology in those days and you just had to make yourself learn how to use it and I did."

Today, Downs is the head of prosthetics for the Veterans Health Administration. He told Pelley the technology used for his arm was developed during the World War II era.

"There's a hook, something out of Peter Pan. And that's just unacceptable," Dr. Geoffrey Ling, an Army colonel and neurologist who's leading the Revolutionizing Prosthetics program, told Pelley

Col. Ling is a physician with big dreams and little patience, especially when touring Walter Reed Army Medical Center and meeting the troops he's working for. "We have a saying in the military, 'Leave no one behind.' And we are very serious about that. And that doesn't mean just on the battlefield, but also back at home," he said.

Ling told Pelley they've made great strides in artificial legs, but a good arm has never been within their grasp. "If you look at your hand, it's an incredibly complex piece of machine. What nature provides us is extraordinary. The opposable thumb, the five finger independently moving, articulating fingers. It's fantastic what this does."

"And when you lose your hand you've lost something that makes you human," Pelley remarked.

"You're so right Scott. Because, think about what makes us separate from every other animal species. We have an opposable thumb. That is, in fact, what makes us human," Ling said.

Ling is determined to give that humanity back. His project is run out of DARPA, the Defense Advanced Research Projects Agency--the same group that oversaw the creation of night vision, stealth aircraft, and GPS.

Ling told Pelley it's a very large-scale project. "It is very much like a Manhattan Project at that scope. It is over $100 million investment now. It involves well over 300 scientists, that is engineers, neuroscientists, psychologists."

A role for Dean Kamen
One of the scientists Ling asked to join the team is Dean Kamen, a sort of rock star in the world of inventors. His creations include dozens of medical devices, and the Segway.

They are inventions which have made him a multimillionaire.

"When the folks from the Defense Department came to this office and said, 'Here's what we need,' what did they tell you?" Pelley asked.

"We want these kids to have something put back on them that will essentially allow one of these kids to pick up a raisin or a grape off a table, know the difference without looking at it. That is an extraordinary goal," Kamen explained.

"He basically said, 'You're crazy.' That's what he told us," Ling remembered. "He said flat out, he and he himself, who's a crazy guy himself, I mean he is very innovative thinking. He's a brilliant man, totally brilliant man, but a mad scientist."

Kamen told Pelley he thought the Pentagon and DARPA were unbelievably optimistic in their expectations and that he told them that.

"He said to us, he said, 'I can do my, you're crazy. But, we're willing to rise to this, rise to the challenge because it's important,'" Ling remembered.

Kamen took 60 Minutes behind the scenes at DEKA, his company in New Hampshire, to show Pelley how inspiration becomes invention.

"Engineers design a part on a computer, he fires it up here on our network," Kamen explained.

His team of 40 engineers spent a year working on the problem. What they came up with was a high-tech, wired attachable arm and hand.

"When you first started this, did you sit down at your desk and look at your hand? And figure out how it worked?" Pelley asked.

"Well, most good engineering is some adaptation of what nature does," Kamen replied.

It all began by creating dozens of gears, joints and computers that mimic nature's design. But then came the hard part: meeting DARPA's demand for an arm no larger than the average human's and no heavier than nine pounds.

Kamen showed Pelley a part of the DEKA arm which contained three processors. "Think of this as three PCs worth of computing power. And all of this just fits, it's round because it just fits in the wrist joint."

Asked what the toughest part of the engineering process was, Kamen replied, laughing, "All of it."

The prototype had 25 circuit boards and 10 motors. But it would be no good at all unless the patients were willing to accept it.

"We went and started talking to the real patients, the potential users, down at places like Walter Reed. And immediately, we were shocked to learn, even just the hollow plastic shell that they wear when they're out and about, it sweats, and it hurts, and it irritates. And we came back and realized that if we build the world's best nine-pound arm, but nobody will wear it because 24 hours a day, or 12 hours a day, of wearing a nine-pound arm is going to be irritating, and frustrating, we said, 'We've got a way bigger problem here,'" Kamen remembered.

So Kamen's team created a new way to connect the DEKA arm to the body using tiny, round balloons.

"And you'll notice now, if I hit this button, these things are inflating. And that's a nice, gentle pressure there. But if that's displaced all over your whole shoulder, that's an enormous amount of structure," Kamen said, demonstrating how the balloons work.

"So, now the arm is gripping tight on the whole you can lift something heavy," Pelley observed, watching the arm in action.

"Right. And as soon as he's not gripping tight and heavy, one or the other might just deflate," Kamen explained.

Trying on the DEKA arm
Kamen asked Fred Downs, the VA official in charge of prosthetics, to take off the hook he'd been wearing for 40 years and give the new arm a try.

The arm Downs tried out is controlled by flexing the shoulder and pressing buttons built into his shoes - almost as if he's typing with his toes.

Downs told Pelley he was very skeptical. "Because I've seen lots of inventions come along in my years of being in charge of prosthetics, and so some great stuff, but in the long run it doesn't really work because your body only has so much tolerance for gadgetry."

After practicing for ten hours, Downs showed Pelley what he could do. He picked up a soda bottle, using his toes to control the grasp.

He was then able to open the bottle and take a drink from it.

"The feeling is hard to describe. For the first time in 40 years, my left hand did this. I almost choke up saying it now. It was just--it was such an amazing feeling. I was 23 years old the last time I did that," Downs said.

"It felt so good to move my arm again--to do things with it. Not as fast, but it worked," Downs remarked.

"You just said 'move my arm...again.' Did it feel like your arm, all of the sudden?" Pelley asked.

"It did. It did. It felt like my arm. It was me," Downs said.

"You're sure I can't take this arm with me? I'm ready for this arm," Downs joked, after trying out the DEKA arm.

If he is eager to have the DEKA arm, imagine what it would mean to Chuck Hildreth, who lost both arms at the age of 18 in an electrical accident.

He's been volunteering at DEKA for nearly two years.

"Now, it seems to me that one of the issues here would be that you don't have any feeling in this hand. So the question becomes, I mean, how do you pick up an egg? How do you pick up something that you might crush? How do you know?" Pelley asked.

"I have a vibrator sensor here that tells me how tightly I'm grabbing things. The more intense the grasp, the more intense the vibration is," Hildreth explained.

In an experiment using a plate of grapes, Hildreth managed to pluck off a grape, without crushing it with his robotic arm.

Consider Hildreth hasn't eaten like this in nearly 30 years--using the arm, it did take him a moment to eat it.

Many of the innovations in robotics that make this possible are already at work in artificial legs. "These are the latest and greatest. These are the 'Power Knees.' They actually have a motor inside them. They help propel me," explained Josh Bleill, who lost his legs in 2006 to a roadside bomb in Iraq.

Last year he became the first person in the world to walk on two of the power knees. They're legs that propel themselves and talk to each other to keep a constant speed and stride.

Asked how fast they can go, Bleill told Pelley, "Faster than I can control, to be honest with you. Not to a run yet, but they do have a lot of power."

Connecting to the nervous system
Now making a robotic arm move as naturally and effortlessly as Bleill's high-tech legs is the next step in revolutionizing prosthetics. Col. Ling says the key is connecting the artificial limb straight into the nervous system.

"Remember, they lost their arm. But that big bundle of nerves that came out of the spinal cord still exists in their shoulder," he explained.

"So the nerves that control the arm are not necessarily lost with the arm and the brain continues to send those signals to those nerves when a person imagines moving their missing limb," Pelley asked.

"That is correct," Ling replied.

Jonathan Kuniholm is uniquely qualified to figure out how to tap into those signals. He's a biomechanical engineer at Duke University who lost his arm to a roadside bomb in Iraq.

"Explain to me what you're doing with your right arm and the sensors, and how that relates to your new right hand," Pelley asked.

"I'm imagining performing movements with my right hand, and when I do that I am moving the muscles that remain here in my arm. When those muscles move they make little electrical impulses that we can detect with these electrodes," Kuniholm explained.

He controls a robotic arm simply by thinking about moving his own hand that no longer exists.

Asked how much training is involved to learn how to move the hand, Kuniholm told Pelley, "I'm not really learning, so much as the computer is. I'm doing what I imagine I'd like to do. And we've taught the computer to interpret the signals and do what it is."

He said it almost feels natural to him.

After four years and $100 million, arms controlled by thought are still a work in progress. But in the meantime, the DEKA arm is headed to the VA for clinical testing in the hope that is will soon becomes available to the nearly 200 arm amputees from Iraq and Afghanistan.

"Nobody ever wants to put a price tag on making a soldier or a Marine whole again. But, you're talking about $100 million," Pelley remarked. "It's a big number."

"It's a huge number. But it does a number of things. Number one is, of course, it fulfills our commitment to these fine your men and women who the issue of money compared to what they have done for the service of the nation becomes immaterial," Ling replied. "However, this is not a classified, military weapons system. This is an advancement in medical technology. And the beauty of this particular effort is that this is another gift of the American taxpayer to the entire world.