ST. LOUIS CO., MO (KTVI/CNN) - A teen learned how to operate a 3D printer to build a custom prosthetic arm for his dad.
Robbie Freis wanted to give his dad a hand, so he built him an arm.
"I decided to create a 3D printed, custom scanned prosthetic arm for my dad, who is an amputee," he said.
The high school senior, who wants to go into robotics in college, designed a three-month thesis project. His mission: to build an arm for his father injured in a 2003 RPG attack in Iraq.
But first, he created an arm adapter for the Nintendo Switch.
"When my dad was injured in the Marines, he wasn't able to play video games with us for about 10 years," he said. "And after I created that 3D printed adapter, he was able to play with us full speed."
Soon, Freis was fine tuning his designs, creating a custom scanned prosthetic modeled after his dad's left hand.
The high school senior mirrored the scan, creating a right-handed model that could throw a ball.
"He knows how to get projects done and come up with amazing things,' said Derek Ward, robotics advisor at Priory School. "He's been on the robotics team for six years now. So just to watch him go from a seventh grader to a 12th grader, I'm not surprised he can pull something like this off."
After a lot of trial and error, Freis figured out a way to craft all the parts on the 3D printer in the school's lab, constructing a design in which his dad controls the finger movements.
Freis is a National Merit finalist who credits mathematics for helping him understand a challenge and working toward a solution.
"As soon as I start to test different alternatives, I start to narrow in on something," he said. "It's sort of more discovery than inventing."
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