Sometimes, the most amazing teams make the most wonderful things happen, and yet, there is just not enough time to finish all the features before the product ships. This is what happened to Raimi, who came to this world missing a right hand and half of her right forearm. Raimi is now 9 years old, and commercial mechatronic prostheses are still only available to those who can afford them. When Raimi’s father approached [Patrick Joyce] to ask him for help in building an affordable prosthesis, he knew it would matter, and went right to work.
[Neal Muzzy], a local member of the Cedar Valley Makers makerspace, just made news on Open Bionics for his robotic prosthetic hand called Dextrus v1.2 which he made for his friend, and wounded war veteran, [Taylor].
In just two months, [Neal] worked with his friend to make this robotic prosthetic with the goal of having it more functional and easier to use than [Taylor]’s current prosthetic. The very first prototype was made by using the open-source Dextrus design, to test fit, and control using EMG sensors. Once they determined it would work — onto customizing!
They call it Dextrus V1.2, and it works better for [Taylor] than the original — but that’s the whole point of the Open Hand project — starting with a base design, and making it better. If you’re not familiar with the Open Hand Project, it was originally crowd-funded on Indiegogo, and is now an organization to make robotic prosthetic hands more accessible to amputees. We wrote about it in Hacklet 41 – Prosthetic Projects.
Just a few weeks ago we were wondering if we’d try to build our own prosthesis if we were ever to lose a limb. This pair of hacks answers that query with a resounding “YES!”.
To the right is a replacement pointer finger. The missing digit took the first two knuckles with it, but there’s enough left to easily interface with this creation. It’s a mechanically clever assembly that moves as you would expect the original to. See for yourself after the break. It seem the maker intended to mold silicone around the structure but never got around to posting an update video.
On the left we have a chinese man who lost his arms while fishing. It seems they were using homemade bombs instead of nets and one went off prematurely. Since then he’s constructed several different prosthetic arms, each with its own special purpose. This one has a saw connected to it but these two write ups on the man show images of him using a fork and wielding a hammer.
Here we see [Easton LaChappelle] getting a congratulatory handshake from the robotic arm he built. This project is aimed at human prosthetics, and we’re happy to report that [Easton] won second place in Electrical and Mechanical engineering division of this year’s International Science and Engineering Fair (PDF listing the winners).
In the video he gives us a great look of the state of the project. Since we checked in with him last he’s added a body for the arm to mount to. The arm now has shoulder movement, which uses geared DC motors along with some potentiometers for orientation feedback. For the elbow he wanted to have the same setup but ran into trouble mounting the potentiometer. His solution was to use some shapelock to mold a bracket (shapelock is the plastic you melt in water to form any shape). In addition to the aforementioned joints, the wrist, fingers, and hand have all seen improvements in how they are supported and in their performance.
We think this is amazing work for anyone, especially a 16-year-old High School student. Great job [Easton]!
After a motorcycle accident that cost him is arm [Martin] and his son [Luke] chose not to give up. They used their considerable mechanical skills to create a replacement robotic arm which allowed Martin to start doing some of the simple things he had been unable to do with the prosthetic he was originally fitted with. There are not a lot of details but it seems the arm has 2 degrees of freedom with a claw manipulator, controlled via chin controls to free up his other arm. For anyone interested in similar projects you should check out the Open Prosthetics Project. There is a short video after the break which tells Martin’s story. If you don’t have an arm, build one, seems perfectly reasonable to us. Nice work guys! We look forward to seeing the next version.