Through contacts with our faculty staff at the School of Engineering and Applied Science, we were introduced to a 10 year-old girl who born with congential limb loss of the left forarm and was learning out to play the cello. Her current prosthetic was not sufficient for playing the cello because of its weight, length, and lack of stable way to attach the bow.
We decided to work on solving this problem by developing multiple solutions or increasing complexity. First, we developed a simple attachment for her existing prosthetic so that served as a placeholder for a more complete design. This allowed us to determine the most comfortable angle for the wrist and finalize the bow grip.
The second major iteration integrated the bow grip with a new custom arm. This design, which is currently in use by the girl, is lighter and better sized that her original arm, and allows for a more secure connection between the arm and the bow grip.
While the current design is sufficient to allow the girl to play the cello, a third iteration is in the works to improve on the ergonomics of the design. This version will add a rotating wrist controlled via a linkage, which should allow the girl to use more of her elbow motion to move the bow instead of her whole upper body.
