Name: Patrick Messimer
Year in school: Senior
Major: Mechanical engineering
Advisor and committee members: Mechanical engineering department chair and professor Brendan O’Toole (faculty advisor), English and Honors professor Maria Jerinic (Honors advisor), and Engineering Associate Dean of Research Mohamed Trabia (committee member)
Professor O’Toole visited my third-grade classroom — his son was in the same class — for a career day to share all the exciting engineering projects he was working on. Despite preparing a full presentation, he was unable to get past the first slide because somebody — me — kept asking questions.
After spending the rest of my time in grade school competing in various robotics competitions and studying for almost four years now at UNLV, I’m still asking questions. Now I do so as a researcher. (And I’ve learned to let professor O’Toole finish his presentations first.)
I’ve helped refine a 3D-printed prosthetic hand that professors O’Toole and Trabia have been designing for children like Hailey Dawson. She has Poland syndrome and needed an affordable prosthetic to help her play baseball. She used her 3D-printed hand to raise awareness for Poland syndrome by throwing ceremonial first pitches at all 30 Major League Baseball parks and the World Series.
The long-term goal of our research is to model every aspect of prosthetic hands in software to improve the design process. This requires an understanding of how printed materials behave when forces are applied to them, and it’s difficult to find this information because 3D-printed materials haven’t been around that long.
My thesis research seeks to understand the strength of Ninjaflex, the material we’re using for the prosthetic hands’ joints. Ninjaflex is a flexible, 3D-printable plastic that resembles rubber. I want to learn how adjusting various 3D-printing parameters impacts Ninjaflex’s strength.
First, I printed dog-bone-shaped specimens with various densities and print orientations, stretching the specimens with a machine until they broke. A sensor on the machine measured how much force I was applying to each specimen, while a camera filmed the experiments. The distance and force data I’ve gathered will reveal how much the material deforms under these conditions and help us design optimal hand joints.
My goals when I began my thesis project were to practice designing credible engineering research experiments and improve my technical writing skills. There’s still a lot of work ahead, but I’m excited about what I’ve already achieved. Additionally, the experience I’ve gained will be helpful after I graduate and begin working as an engineer at Pololu Robotics and Electronics, where I’ll help develop new products and manufacturing tools.
