Skip to main content
Part of complete coverage on

Thought-powered bionic arm 'like something from space'

STORY HIGHLIGHTS
  • 'World's most sophisticated' bionic arm is controlled by the mind
  • Modular prosthetic Limb includes computer in palm of hand
  • Seven years in making, valued at tens of thousands of dollars
  • Positive psychological benefits for amputees

Editor's note: Art of Movement is CNN's monthly show exploring the latest innovations in art, culture, science and technology.

(CNN) -- The idea of an amputee tinkling on piano keys with all the flair and grace of an able-handed person may seem like a futuristic fantasy.

But watch Johnny Matheney effortlessly arch and extend each finger on his bionic arm and you can't help but agree with him when he says: "The future is coming now."

Its makers describe Matheney's robotic limb as the most sophisticated of its kind in the world, recreating virtually every movement of a natural arm -- and all controlled by brain power.

"When they took my arm I never thought I would have an actual hand -- I saw the hooks and thought that was exactly what I would be getting," said Matheney, who lost his left arm to cancer in 2008.

Bionic man plans to help amputee victims
The bionic hand with the human touch

"So once they introduced me to this, it was like something out of space come to Earth."

Explore the bionic body

Moving on up

Featuring 100 sensors, 26 joints, 17 motors and a tiny computer built into the palm of the robotic hand, the revolutionary Modular Prosthetic Limb (MPL) is the work of researchers at Johns Hopkins University in Maryland.

Weighing four kilograms -- much like a normal arm -- it can mimic almost all the same movements. "This is the most sophisticated arm in the world," said Michael McLoughlin, of the university's Applied Physics Laboratory.

"What we have done is, by order of magnitude, increase the ability to do very highly dexterous kinds of motions. So you can think about things like eventually playing the piano ... I think we'll get there someday."

The MPL is programmed to respond to electrical impulses in Matheney's residual limb -- he simply has to think about moving his old arm.

"You don't even really think about it," said Matheney. "You're extending the arm, talking and doing other things -- it just automatically does it."

Nerve Center

For former baker Matheney, the first step in the ground-breaking project was bringing to life the dead nerves at the end of his residual arm.

Matheney underwent targeted muscle reinnervation -- surgery that involves rewiring electrical signals in the stump. Only 50 people in the world have had the operation, which takes a couple of hours.

Read: Surreal prosthetic limbs push boundaries of art

"We take all the electrical signals that are going down to the missing limb and reroute them into residual muscles that are still there," said Albert Chi, assistant professor of surgery, trauma and surgical critical care at the university.

"Now when Johnny has a natural thought about moving that missing limb, he contracts that muscle and we are able to capture those signals and translate them into messages for the prosthetic limb."

There is an elegance to it, and that is one of the most important things for the users of prosthetics
Michael McLoughlin, MPL innventor

Within two weeks of surgery, Matheney began to feel his phantom limb for the first time in years. He practiced moving it for 20 minutes each day, training the nerves for his new bionic arm.

"The more you do it, the more the pathway is cleaned up and the cobwebs are out of it," he said.

"After the surgery I was constantly rubbing my stump to see what new feeling was coming in. I said 'Wow I can feel my pinky finger.' I kept on doing it, and it was like 'Oh right, I've got a pointer.'"

Symphony of movement

The ambitious bionic limb, seven years in the making, is incredibly lifelike in its movements, thanks to a complex symphony of muscle triggers. Other robotic arms have relied on direct signals, whereas the MPL picks up a chorus of muscle motions -- creating a more fluid movement.

Read: Are bionic superhumans on the horizon?

"We are using a lot more electrode sites," explained biomedical engineer Courtney Moran. "That array of muscle contraction is more like a chord in music, so you are able to get more complexity of motion -- like you would get more complexity of sound."

Looking good

While many prosthetic limbs look lifelike, finding one that also moves naturally has proved more of a challenge.

There are now plans to cover the MPL in a skin-like substance, which could make it the most inconspicuous artificial arm in history.

"There is an elegance to it, and that is actually one of the most important things for the users of prosthetics," said McLoughlin. "The natural movement is almost more important than the appearance."

Indeed for Matheney, the bionic arm feels just as natural as the arm he lost -- to the point where "every time I have to turn it back in, it's like losing part of me all over again."

"I do a lot of handy work around the house, a lot of cooking," he says. "And to be able to hold bowls and grab spoons is absolutely amazing."

ADVERTISEMENT
Part of complete coverage on
July 20, 2014 -- Updated 1540 GMT (2340 HKT)
Some contend that larger weapons have come into Ukraine from Russia.
July 20, 2014 -- Updated 0057 GMT (0857 HKT)
Children and youth are often the victims of the violence in Gaza. CNN's Ben Wedeman reports.
July 22, 2014 -- Updated 1311 GMT (2111 HKT)
A nun, an AIDS researcher, an athlete and a family traveling on summer vacation. These were some of the victims aboard MH17.
July 18, 2014 -- Updated 0621 GMT (1421 HKT)
In an ambitious plan to upgrade urban India, Prime Minister Narendra Modi says he will build 100 "smart cities" across the country.
July 20, 2014 -- Updated 1127 GMT (1927 HKT)
Inspirational, creepy or just weird? CNN meets the 51-year-old man who dresses like a schoolgirl.
shakespeare moon illustration
It's been 45 years since the first moon landing. And still the giant rock continues to intrigue.
July 18, 2014 -- Updated 1249 GMT (2049 HKT)
Nelson Mandela
21 ICONS has captured intimate portraits of some of South Africa's most celebrated. Founder Adrian Steirn reveals the story behind the images.
July 17, 2014 -- Updated 1100 GMT (1900 HKT)
A British nanotech company has created what it says is the world's darkest material.
July 18, 2014 -- Updated 1112 GMT (1912 HKT)
Yoga, meditation and watching a snake eat a frog alive: these are some of the experiences to be had at this Himalayan yoga retreat.
July 17, 2014 -- Updated 1139 GMT (1939 HKT)
Just a few weeks ago, a boy tied to a bus stop in Mumbai barely received a glance from passersby. Now, he has a home, thanks to a local NGO.
CNN joins the fight to end modern-day slavery by shining a spotlight on its horrors and highlighting success stories.
Browse through images from CNN teams around the world that you don't always see on news reports.
ADVERTISEMENT