Jon Ruonavaara of Kalispell lost all his fingers to frostbite during a hunting accident in 2010. Since then, he has been outfitted with hook prosthetics.
Recently, however, Ruonavaara was outfitted with a Robohand prosthetic created on Whitefish High School’s 3-D printer by 18-year-old Georgia Donaldson.
Ruonavaara plans to use the prosthetic as a prototype to develop for his specific needs.
The Robohand prosthetic was Donaldson’s advanced chemistry project. Donaldson, who graduated from Whitefish High in May, plans to major in plastics and composites engineering at Western Washington University.
Her teacher Todd Spangler knew this was the right project for Donaldson’s yearlong senior project. Donaldson created demonstration hands, but her initial goal was to outfit a child with a complete prosthetic. Donaldson said Robohand was tailored for children who quickly outgrow expensive prosthetics.
After a story about Donaldson’s search for a candidate appeared in the Daily Inter Lake in November, she was connected with 29-year-old Ruonavaara, an electrical engineering student at Flathead Valley Community College.
“I was definitely excited,” Ruonavaara said. “The hooks are usable but they’re not ideal. There’s certain things that hooks don’t work well for that this hand would probably work better. For grabbing things that are flat, I can get pretty good grip [with hooks], but anytime you grab a round object like a pop can, a hook would just crush it where a hand could go around it.”
On June 2, Donaldson and Ruonavaara met in Spangler’s classroom. He tried on the prosthetic, and although it doesn’t quite fit, he showed how it worked.
The Robohand looks like the jointed skeleton of a robot hand. The simplistic design functions on a pulley-style system using elastic and nylon cabling to do a basic grabbing motion. When the wrist bends, the wires pull the digits downward.
Donaldson downloaded free open-source digital blueprints published online by Robohand (a South African nonprofit) and modified the measurements. Meeting to size and fit the prosthetic proved to be the biggest challenge for the two students on different schedules.
“We measured him as best as we could. What we would do is we would create a bigger frame using the 3-D printer which is pretty easy. So we didn’t have enough time in this year,” Donaldson said. “It’s a prototype and we just wanted to get the mechanics down and figure out what would work best. So this is the first edition of our type of Robohand.”
Ruonavaara plans to modify the prosthetic with help from another electrical engineering student. Having a model will be a time saver, he said.
“Without a model like this, I would probably have to go through a learning curve,” Ruonavaara said.
Adding electronics would make it suitable for everyday wear, Ruonavaara said.
“My main concern is in order to hold an object I have to flex my muscles, and so if I’m walking for 10 minutes holding something it wears my arm out,” Ruonavaara said. “That’s where electronics would come in — electronic motors.”
Robohand was created by Richard Van As of South Africa when he was unable to find an affordable prosthetic to replace fingers cut off in a woodworking accident.
In 2012, Van As successfully designed a working prototype. In 2013, he turned to 3-D printing technology to cost-effectively manufacture the prosthetic.
Ruonavaara said cost is a major factor in choosing a prosthetic. After his accident, Ruonavaara wanted a myoelectric prosthetic with a cost-prohibitive price tag of $90,000 that insurance wouldn’t cover, he said.
“The way I look at it is if my injury happened 100 years ago I would be fitted with hooks, and now I’m fitted with hooks. I think with the technology we need to make it accessible to the average person and this is one way that that can happen,” Ruonavaara said. “You’re not going to get the same product as a $90,000 hand, but it’s also not going to be $90,000.”
While he didn’t get the prosthetics he wanted, Ruonavaara said the hook prosthetics have been very reliable. He added that in his experience, people don’t wear prosthetics around the clock, whether high- or low-tech.
“I use no prosthetics the majority of the time. It’s more activity-specific. For example, if I was driving and the hand helped me to drive I might always use it to drive, or for eating, but then I would take it off,” Ruonavaara said. “It’s like a good fitting shoe: I don’t mind wearing it, but at the end of the day you’re glad to take it off, as with any prosthetic. That’s why the easy-on easy-off [Robohand design] is a good option.”
Donaldson said she was grateful for Ruonavaara’s participation to carry her project through to a final product.
“It was helpful to work with Jon,” Donaldson said. “He had a lot of ideas that I wouldn’t have even considered.”
Reporter Hilary Matheson may be reached at 758-4431 or by email at firstname.lastname@example.org.