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Discussion Starter #1
My son Alex was born with ABS (Amniotic Banding Syndrome), resulting in a shortened left forearm & palm with only one finger/thumb (more thumb-like in operation, but in the relative position of an index finger).



We have inquired over the years into several options including prosthetics, and were always advised to wait until he was at least 4 or 5 years old.


Recently, my wonderful wyfe, Sally, saw a report on TV about simple-to-make robotic hands, and she put me on the research trail where I found the e-Nable organization with it's totally open-source software and hand designs (relatively inexpensive hands to end-users). The big drawback is a 6-month waiting list.



So, I did a bit more research and snatched an almost-new 3D printer of my own on e-bay.



It didn't take too much to get the printer humming, but it took 29 hours to complete the print job! I sat next to that printer for almost 18 of those hours, monitoring the progress, taking pictures, and attempting to correct for unanticipated errors due to the sensitivity of the printer to it's immediate environment.



In the course of the printing, some flaws in the project became evident which were caused by incorrect preparation and incorrect software settings due to the unknown specifications of the print media that was supplied with the printer.




Anyway, I easily corrected the errors with a little bit of work and some 2-part epoxy glue and putty.



End result: Alex has his first RoboHand! It's a "Raptor" design (very basic).



A couple of drawbacks besides the print flaws: It is too small for his chubby arm and palm, the wrist joint won't fit "flat" in the joint space, so the range of motion with the wrist rotated in place requires excessive force to produce a very weak grasp (I will scale up the print size on the reprint). Also, I selected the heavier elastic cord from the two sections that were included in the hardware kit, that resulted in even more effort to clench the grip (I'll use the lighter elastic cord on the re-print).


Alex about to hand his Mom a flower he made-



So, Blue & Red spools of media are on order, a printing area enclosure being planned (shouldn't take more than a few hours to set up), and the 2nd iteration will be MUCH better!


And now, back to the shop to pay for the printer...
 

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That is really awesome. How do the fingers activate? I can imagine as a parent you would do anything to give him the chance to have a hand like that, can't imagine how hapy you are.
 

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Discussion Starter #3
By flexing his wrist downward, the tensioner strings that are anchored at the gauntlet (forearm) draw the fingertips in.

Elastic cords retract them when he releases pressure.

Yep, we're pretty dang excited. We can re-print scaled-up hands as he outrgrows them, too.

We're also going to be an area resource for people who don't have a printer, but need a hand.
 

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Man I wish i lived near you. I used to do a fair amount of robotics with high school kids, plus some other odd and end things, and I would love to be involved in this!

That's awesome!
 

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Man I wish i lived near you. I used to do a fair amount of robotics with high school kids, plus some other odd and end things, and I would love to be involved in this!

That's awesome!
You don't need to be near me, just check out Enabling The Future ? A Global Network Of Passionate Volunteers Using 3D Printing To Give The World A "Helping Hand."

There are ELEMENTARY school kids, cub scouts, and other youth groups making these hands all over the US and in many other countries. I still can't believe they aren't being mass produced in China yet...
 

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Nice work there was a new story up here in Massachusetts of a father son team that did the same type of hand jus last winter.

Really cool what 3d printing can do now
 

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I thought the title of this thread was some weird name for a bike project but this is SO much better.

Awesome job - well done!
 
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