eNable 3D Printed Hand

This page documents the initial build of an e-Nable 3D printed prosthetic hand for Khamareon, a 10 year old student from Stockbridge, GA

I am working on this with staff from Khamareon's school as well as a small team that I rallied from the Maker Station makerspace in Marietta. Files for 3D printing the hand can be downloaded using the buttons on the right.

Team Members:
Recipient: Khamareon, Teachers: Cassie N, Shawn G, Makers: Tanju B, Bret L, Mike S, Beverly L, Mycheal J, Jay D

Below is a brief summary blog of milestones as well as details about e-Nable.

Doh!, May 11, 2015

Well it only took a little more than a week for the hand to break. It broke at the hinge joint between the palm and gauntlet parts
We suspect that it broke at an adhesion layer in the plastic most likely due to it being printed out of HIPS filament material. It's also possible that we didn't drill the hole big enough for the Chicago screw at this location. Since the first hand was a little difficult to operate, we're printing out a replacement based on a different design called the Raptor Reloaded.
This design uses printed pins for the connectors instead of screws and is supposed to to have improved geometry for the tension and elastic cables used for operating the hand. Printing is now in process.

Handoff, April 30, 2015

Khamareon got his new hand today! It was pretty exciting to see it on. The hand is a little difficult to operate and it appears that it may need a bit more tension in the tension line. Cassie and Shawn will be working with him over the coming weeks to assess the fit and figure needs for the next iteration

Hand Assembly - Strung out over stringing up the tensioners, April 11, 2015

We got strung out stringing up the hands this past weekend, but we made good progress this past weekend. Just need to tune them now and add the velcro.

Everyone agreed that this part of the assembly process is much harder than the actual printing. Nevertheless, we're on track to have them ready by April 30. Woot!

Also earlier in the week, I accidentally bought the wrong length binding post screw twice in a row... I was tired of going to the hardware store, so instead decided to trim the screw down to the needed length. The screws are aluminum and easy to cut with a hack saw, but they are too small to hold, especially since I only needed to trim 1/8" off. So I designed and printed up this little cutting jig that worked like a charm.

1st Meeting & Initial Prints, April 3-5, 2015

It took us a couple of iterations trying to work off of a photograph to understand the general sizing input for enablethefuture.org's handomatic scaling tool. From a photograph, I input a reference dimension of 69.9 mm off of his left hand. This output a model that had a width of approximately 64mm as seem in the picture below.

After getting a chance to meet Khamareon and get a look at his hand inside of the test print, I decided to reduce the width by an 1/8 inch. This was eye-balling it because I forgot to take a picture amongst all the excitement of the first meeting. I ended up using a reference dimension of 67 mm.

Using a 67 mm reference dimension input to the handomatic, I generated a new cyborg-beast model and shared with Brett to have him print the fingers on his Up printer at home. I printed the palm and gauntlet on the new LulzBot Mini down at the MakerStation. The prints look pretty good. We now need to procure the remaining hardware and will pursue assembly within the coming weeks. Target hand delivery date is Apr 30.

Pending Hardware

• Chicago Screws
• Velcro
• Foam padding
• Shade Cord
• Elastic Cord
• Sleeve Arm Protector

Pics of Prints:

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About The Maker Station makerspace

The Maker Station is a collaborative, shared workspace where curious and like-minded individuals can come together to work on projects, discover new areas of interest, develop a new business idea, or simply grow their personal hobbies. The space serves the interstate corridor northwest of Atlanta, GA. This includes Marietta, Kennesaw, Acworth, and surrounding areas.

• Main website: www.themakerstation.com/
• Events: www.meetup.com/Cobb-County-Makers-Meetup/
• Facebook Group: www.facebook.com/groups/CobbCountyMakers/

About e-Nable

The e-NABLE community and the “3d Mechanical Hand – Maker Movement” that was inspired by two strangers (a prop maker from the USA and a carpenter from South Africa) that came together from 10,000 miles apart – to create a prosthetic hand device for a small child in South Africa …and then gave the plans away – for free…so that those in need of the device could make them for themselves or have someone make it for them.

What originally started out as a couple of guys who created something to help one child in need…has grown into a world wide movement of tinkerers, engineers, 3D print enthusiasts, occupational therapists, university professors, designers, parents, families, artists, students, teachers and people who just want to make a difference.

• Main website: www.enablingthefuture.org
• Handomatic Web Application: http://enablingthefuture.org/handomatic/
• Cyborg Beast Hand: http://enablingthefuture.org/upper-limb-prosthetics/cyborg-beast/