STEVE INSKEEP, HOST:
Two men on two continents found a new use for a new technology. The technology is 3-D printing. It's promising a revolution in how many things are manufactured and designed. The two men are a carpenter in South Africa and a mechanical puppeteer from Washington State. Together they designed a 3-D printable prosthetic hand for children. NPR's Steve Henn reports.
STEVE HENN, BYLINE: Two hours north of Seattle, Ivan Owen, a special effects artist, turns on his 3-D printer.
IVAN OWEN: This is essentially like a robotic hot glue gun.
HENN: Hot plastic soon squeezes through the tip, laying down layer upon layer until it can form anything from a simple plastic square to a finger.
OWEN: The complexity of the human hand has always fascinated me, really captured my imagination.
HENN: One of Owen's specialties is making large mechanical puppet hands, but these hands actually don't require a 3-D printer. The printer's here in Owen's home because it was donated by MakerBot, the manufacturer. To understand why Ivan Owen got a free printer, we have to go back a bit and meet Richard Van As. Van As is a carpenter.
RICHARD VAN AS: I make all the high end stuff. That's what I do.
HENN: He lives halfway around the world, near Johannesburg, South Africa, and in the spring of 2011, Van As was working with a circular table saw in his shop.
AS: It's a possibility that it was a lack of concentration, or you become a little bit sort of cheeky with the machines. It's just the inevitable happened, you know?
HENN: An accident where he lost two fingers and mangled two more. For a carpenter, this was his livelihood. But buying a prosthetic was financially impossible. It would cost thousands and he wondered about the cost of replacements and repairs. So in the meantime he rigged up an artificial index finger for his right hand with anything he could find in his shop.
AS: It's actually not so easy to actually mimic what nature's all about and what a tendon and all these things can do. So it was trial and error, frustration, throw things away, try again.
HENN: After a few weeks, Van As had something functional. But he kept looking for new ideas, help, even a collaborator.
AS: I don't think there's a website I've not been on, from the tinkerer to the professional robotics.
HENN: And then he stumbled upon Ivan Owen on YouTube, demonstrating one of his big puppet hands where thin steel cables act like tendons and allow metal digits to bend. Van As emailed Owen and the two began working long distance, Skype-ing, sharing ideas, even sending parts back and forth.
OWEN: If we wanted to refine it, we had to try and build a copy of what the other person had created, then decide what to refine on it or what to change.
HENN: Months passed and a friend of Van As donated frequent flyer miles so Owen could come to South Africa and finish the work in person. And today Van As has a working mechanical finger to assist him with his job. But something else even more seminal occurred on that short visit. Van As received a call from a South African woman whose five-year-old son Liam was born without fingers on his right hand.
AS: I didn't know what amniotic band syndrome was until then.
HENN: Amniotic band syndrome, or ABS, happens to fewer than one in 1,000 kids. Sometimes fibrous bands in utero can wrap around a hand or a foot and cut off the circulation to the digits as they develop.
AS: And would we see if we can help him. Me and Owen looked at each other type of thing and said, yeah, easy. No problem.
HENN: Within days, they ended up developing a crude mechanical hand for Liam with five aluminum fingers that opened and closed with the up and down movement of Liam's wrist. Ivan Owen still remembers Liam's reaction when they rigged the device on him for the first time.
OWEN: He bent his wrist and made the fingers curl. You could see the light bulb go off and he looked up and he said, it copies me. It was a really incredible moment.
HENN: And this is where 3-D printing enters the picture. When Ivan Owen flew back to the States, he wondered if the device they're now calling robohand could be turned into printable parts. He emailed MicroBot to see if the company would help out. By now there were a few videos on YouTube to watch, including Liam being coached by his mother to pick up a ball.
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UNIDENTIFIED WOMAN: Nice.
AS: They came back to us and said, listen, guys, would you consider accepting a donation of two printers, not just one. We said, oh, great stuff. You know, then there was no stopping us, of course.
HENN: What had taken weeks or more, milling finger pieces, adjusting and tweeking, now took 20 minutes to redesign and print and test. Eventually Liam's crude hand was replaced with the improved 3-D printed version.
OWEN: After practicing with it for a little while, Liam was able to pick up a coin, grab objects of different shapes and sizes. He's a really determined little guy.
HENN: And with the 3-D printer, parts for the new hand could be replaced quickly. You can scale up the size of the hand as the child grows. So they put the design and instructions on Thingiverse, a website where anyone can download it and make a hand for themselves with parts costing just $150. That is, if you have access to a printer and the time to assemble it.
PAUL MCCARTHY: This is Paul McCarthy. We live in Marblehead, Massachusetts. This is my son Leon McCarthy. He's 12 years old, was born with amniotic banding so he has no fingers on his left hand.
HENN: McCarthy and his son worked together to make a Robohand using a friend's 3-D printer. Printing parts was easy, but it took them a month to figure out how to string, screw and bolt it together into what they describe as the Frankenstein version. It's still a work in progress, but several weeks ago Leon McCarthy wore it to school for a tryout.
LEON MCCARTHY: I'm able to hold a pencil, piece of paper. I've done a lot more than I ever thought I could, so it's opened up a lot of new doors in my life.
HENN: Paul McCarthy says there were few suitable options for Leon. The doctor's advice when he was very small, get used to the hand without prosthetics, acquire full range first.
MCCARTHY: So the last time he went to visit his hand doctor, he recommended maybe we could start looking for prosthetics.
HENN: And that's when Paul McCarthy found the YouTube videos of little Liam in South Africa. And Liam was just the start. Richard Van As has been besieged with requests. He's personally fitted over 100 children with robohands in between work and his job. He charges nothing. It's been hard for Van As to say no, but he'll soon have to. In the meantime, he's raised money and is hoping to train others to help.
AS: You know, many hands make (unintelligible) work, so the more people that are doing this, more and more people will get hands.
HENN: Like 12-year-old Leon McCarthy, whose dad, Paul McCarthy, will never forget his son's reaction the day he wore his robohand to school for the first time.
MCCARTHY: He comes bouncing out of school with, like, this biggest smile. It was like, look-it, it's working, you know? The Frankenstein hand is functioning. I am holding my lunch bag.
HENN: Getting the fit just right has been hard. Experts in prosthetics say users are bound to have these kinds of complications, but with proper support many see tremendous potential. Robohand offers similar functionality to prosthetics that can cost thousands. And the world of 3-D printing is moving fast. Last night, MakerBot released a new improved version of robohand designed to snap together like Legos.
Materials for this version cost just $5. Steven Henn, NPR News.
INSKEEP: I'm looking at some amazing images of this hand in action. And you can look at them too. Just go to our website, NPR.org.