Advanced prosthetics have come a long way in the last few years, but the costs have also skyrocketed. A cheaper alternative may be on its way thanks to Easton LaChappelle, a 17-year old high school student from Colorado, who is using free online resources and the boom in inexpensive 3D printers to develop a functional prosthetic arm and hand. His projects have already earned him an invitation to the White House, and he's now working at NASA on the Robonaut team.
It all began when he was 14, when he decided to try to build a robotic hand using Lego. At the time he knew next to nothing about electronics, but learned through sites like Instructables how to get the hand to open and close its fingers using a combination of fishing line and servo motors. The project earned him third place at the 2011 Colorado State science fair.
It was there that he met a 7-year old girl who was wearing a state of the art prosthetic that cost an astounding US$80,000. Upon hearing that figure, LaChappelle became determined to design and build an inexpensive alternative. He soon discovered that manufacturing anything the old-fashioned way was prohibitively expensive, but luckily he had a friend with access to a 3D printer. He began working with Solidworks, a 3D modeling program, and looked for ready-made parts on Thingiverse, an online repository of open source models.
Soon he had designed an arm to go with an open source hand, both of which could be printed by his friend. Excluding the cost of the 3D printer itself (in this case, a sub-$1,000 Printrbot), the total cost was about $250. That project earned him an invitation to the third annual White House Science Fair, where he presented the arm to none other than US president Barack Obama. The president shook the prosthetic's hand and suggested LaChappelle show it to DARPA, which is funding the development of advanced prosthetics.
These days LaChappelle is working at NASA's Johnson Space Center, where he's helping out the Robonaut team with telerobotics control. However, he hasn't forgotten that little girl he met at the science fair. "My goal for all of this is to create an affordable prosthetic," he tells me by email. "I am continuing my work to achieve that goal. I have started on the 3rd generation of the arm which will easily top everything so far!".
The new arm is more capable than the last, thanks to bigger gearboxes and multiple worm gear sets in one. And the new version of the hand moves all the motors that drive its fingers to the inside of the palm. They're small but powerful geared DC motors that can be controlled very accurately. He says that altogether, the new arm sports "extreme strength, functionality, costs under $500, and weighs less than a human arm."
While perfecting the new arm, LaChappelle has also helped out with related projects, such as this home-made prosthetic we covered earlier. And since meeting the president, LaChappelle was invited to show his arm at a TED conference. You can watch his presentation below, and follow his ongoing progress on Facebook and YouTube.