The Purdue 3D Printed Prosthetics club works with e-NABLE, an open source prosthetic development community to develop one-off prosthetic devices to meet a clients specific needs.
Initial Prototype:
The first step in development that I played a role in was the manufacturing, assembly, and testing of the first prototype prosthetic hand for a young boy whose arm stopped at about mid-forearm.
This prototype served as a proof of concept for the mounting strategy we would use to attach the prosthetic to the child’s arm as well as a cord and linear actuator-based finger articulation scheme.
What Worked:
The final form of the prototype (pictured left) was able to move each digit and hold onto small and light objects while operating on its own battery.
What Didn’t Work:
The largest problem was the lack of grip strength the fingers were able to exert. Several factors contributed to the lack of grip strength. The primary issues were a lack of force generated at the motors as well as the numerous losses due to friction through the joints and where the internal cords rubbed against their guides.
Future Iterations:
On the left are images of the two prototypes being developed to address the problems of the initial test. The driving idea behind both concepts is to switch from a system that transfers linear forces through cables to a torque-based system using either gears (right) or a combination of gears and belts (left).
My Roles as a Leader:
During my time with the Purdue 3D Printed Prosthetics Club, I spent time as both a project lead for the development of the thumb articulation mechanism and later the lead mechanical supervisor for the prosthetic development as a whole.
Responsibilities:
In both of my roles, I was responsible for coordinating groups of 3 and then 12 people from the onboarding process to prototyping to the final manufacture of mechanisms and all of the associated interdepartmental work that went along with that.