11th Grade STEM

Improving 3D Printed Prosthetic Hands

My name is Emma Carangi and I am an 11th grade student at West Islip High School in the STEM Academy. This year, I will be studying the biomechanics of a human hand, researching 3-D printed prosthetic hands and evaluating how closely those prosthetics emulate human movement. I will then be using that research to try and create a better way to make a 3-D prosthetic hand that can more closely replicate the capabilities of a human hand. In the future, I will try to create a mechanical model of a prosthetic hand.

These are my initial engineering notebook entries of my research on the anatomy and degrees of freedom of the human hand.

This is the assembled palm of the 3D printed hand I printed from Thingiverse.

This is the fully assembled 3D printed hand I printed from Thingiverse.

This is my first attempt at drawing a finger for the prosthetic hand in Inventor. This model is only from the metacarpophalangeal joint to the tip of the finger. Since both the proximal and distal interphalangeal joints do not significantly contribute to the overall degrees of freedom of the hand, in order to simplify, I am making from the metacarpophalangeal joint up one segment and from the proximal interphalangeal joint angled down for a better grip.

This is the assembly I created in Inventor to see how the knuckle joint would connect and what changes need to be made to redesign the joint connection.

This is my initial engineering notebook entry as I started to design the palm of the 3D printed prosthetic hand. I decided to change the finger joints to a ball and socket style joint to allow for more ROM.

This is my first attempt at creating the "ball" of the ball and socket joint for the metacarpophalangeal joint. One concern that I have is that the connect between the sphere and the end of the metacarpophalangeal is too thin and would easily break once 3D printed.