3D Printed Prosthetic Hands - Multi-positional thumbs

I got involved in this project for 2 years and worked on various sub-projects: haptic signal sensing fingers, multi-positional thumb, rotational wrist, and socket composite. This work contained my effort to be an engineer, my countless-sleepless nights, and all of my skills.

I am lucky to know Ivan Owen who my Professor refers as "the 3D-printing wizard." What I have learned from Ivan, both technical and social skills, are far more valuable than I could possibly describe. I started to work with Ivan in October 2014 to develop a 3-D printed prosthetic hand. This hand requires about 13 hours of printing and 30 min to assemble, and costs about $14 of PLA (Poly Lactic Acid - a biodegradable plastic). It is modular which will fit patients with huge age range. All of this projects revolved on working on 3D modeling (as we mainly used Solidworks, Tinkercad and Fusion 360).

My first project was create "A multi-positinal thumb 3D printed prosthetic hand." Our team included Robby Shaffer (Lead), Jake Shriner, Katy Kuznetsova, and myself. This project objective is to design the thumb with two possible positions - cup-holding and key-holding. Please take a look at our final product in the following video.

Unfortunately, I updated my Solidworks software from 2014 to 2015 which now I cannot see any of my Solidworks 2014 files. You can visit the google files link: https://drive.google.com/folderview?id=0B_d2QNTVOt65cTlGLXQ3YUVOOVE&usp=sharing for some progressive files.

This is our metacarpal design for the thumb. This is longer than other finger's metacarpal based on the biological fact.

This is the palm of the 3D printed hand that I have created by Solidworks. This picture only show the top of it. The bottom of the palm is hollow for user to slide their palm in.

These are printed iterations. Every part that we designed, we printed out to test. We met a lot of tolerance issues when working with 3D printers. Even though it showed that parts are perfectly fit together, we could ran into problem such as extra piece of plastic, gravity, printing orientation,...

One of the teammate was working on wiring the elastic cord to activate the finger correctly for holding action.

I had a wonderful experience working on this project. I have learned both technical skills and social skills. This is my very first project that I worked on at the university, every one in the class was trying to get to know each other, and every one of us in this project got closer after the project. Personally, I got to present this project at the Undergraduate Research Conference 2015 at Eastern Washington University, and the Research Symposium at University of Washington 2015.

(There are more than 50 people in the room which I was very surprised)

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