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# System prepended metadata

title: Enable prosthetics

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# What is it?

e-NABLE is an online global community of “Digital Humanitarian” volunteers from all over the world who are using their 3D printers to make free and low-cost prosthetic upper limb devices for children and adults in need. The open-source designs created by e-NABLE Volunteers help those who were born missing their fingers and hands or who have lost them due to war, natural disaster, illness or accidents.

[Their Website](https://enablingthefuture.org)

# Where do we come in?

We are planning to contribute and be one of the volunteers providing these upper limb prosthetics.

# Exploring 3D printing

Now I'm personally getting into 3D printing for the first time so there's lots to learn. we decided to try printing out two models made by Ishaan and I on the first day. I used my Mech, which i made in an earlier cycle.

![](https://hackmd.io/_uploads/HkA146Gun.png)

I installed Ulti-maker to preview what the print would look like and ran into the first problem. 

![](https://hackmd.io/_uploads/rJUoNTMOn.png)

The model had multiple extraneous planes and loads of issues with the topology that would create problems while printing. So I thought i'd try printing each part one by one. Decided to start with the gunner left arm. 

![](https://hackmd.io/_uploads/HJgZr6Mun.png)

![](https://hackmd.io/_uploads/r1ZLSTzuh.png)

Cleaned it up as much as I could and checked it on ulti-maker. The model wasn't too bad so I decided to go ahead with printing.

![](https://hackmd.io/_uploads/HJuWLTz_h.jpg)

![](https://hackmd.io/_uploads/S1oGUTMOn.jpg)

So the models came out.. alright, the scaffolding was super messy. the smaller model came out incomplete, but the bigger one does look quite nice, needs some cleaning is all. I think bigger models definitely work better for cleaner prints.  

# The Upper Limb Prosthetics

I've reading up on each of the prosthetic models available on the E-nable website and 3D printing wise, they're all very viable. One thing that might be an issue is that there are a ton of materials we need outside of the 3d printing materials, namely **Screws, Fishing lines and Dental bands**.

Other than that there are two main types of prosthetics, Wrist actuated and Elbow Actuated. The mechanics of each are quite simple to understand, in both there are fishing lines running through the mechanismm which creates sort of a pulley system connected to each of the fingers. whenever the wrist or elbow moves back or forth, the fishing lines pull on the fingers and close the hand. The Dental bands and screws keep the whole structure together and stable.

## Wrist actuated prosthetics

### The Pheonix V2

When I was combing through the different prosthetic hands available, this one had the most comprehensive assembly parts and instructions. So I thought we could go ahead with this one for the first test print. It's also important to not that it had scored really well on the device ratings list.

![](https://hackmd.io/_uploads/rJP0OCLun.jpg)

![](https://hackmd.io/_uploads/rydkYCU_3.jpg)


Handed the STL files over to Nataraja and we've begun printing the prosthetic hands. He told the PLA being used is super old so it's gonna likely break a lot and printing could take a long time because of that. 

![](https://hackmd.io/_uploads/BkZsr6cO2.jpg)

The first print came out quite well, we just print the finger so far. It could use some work, needs to be more smooth and clean.

![](https://hackmd.io/_uploads/ry3GUaqdh.jpg)

![](https://hackmd.io/_uploads/SJSmIp9un.jpg)

We tried printing the screw and adding pivot as well, but that's still a bit stiff and could use a lot of work. Need to find a way to make it smooth and easy to use.

![](https://hackmd.io/_uploads/ryXFU6qOh.jpg)

Apparently the low quality of the filament lead to the nozzle getting clogged quite often and printing took a little longer than expected. Not the best state for printing much larger projects, regardless all the parts did get printed.

![](https://hackmd.io/_uploads/Hy9u_Y1in.jpg)

We began assembling the arm together after. The palm and fingers came together quite well but the movement was still a bit too stiff. After spenting a lot of time sanding down each of the pieces the movement came out quite smooth.

![](https://hackmd.io/_uploads/Hkuh5Yyjn.jpg)
Initial Hand

![](https://hackmd.io/_uploads/B1CAcKksh.jpg)
the hand almost fully assembled


The wrist piece came out flat and we had to bend it into the right shape, The filament itself wasnt flexible but I Found a way to use a heat gun to melt the filament slightly to make it a little bendable. I molded it into the right shape but the shape was too small.


![](https://hackmd.io/_uploads/S16lqtkjn.jpg)

![](https://hackmd.io/_uploads/SkSm5Kkj3.jpg)

We printed another wrist piece, bigger this time and i bent that around to fit my wrist better. Came out alright in the end.

![](https://hackmd.io/_uploads/HkSLatki2.jpg)

Now only adding some dental bands and fishing lines(or something equivalent) is left. The quality isn't the best but it's servicable for a first prototype.