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Tennessee Tech: Murfreesboro drummer gets prosthetics from Tennessee Tech engineering students

June 4, 2024

Sometimes in life, we all need a helping hand. That’s what one program at Tennessee Tech University is all about.

Tech Engineering for Kids (TEK) matches a child with a special need to a team of Tech engineering students in Stephen Canfield’s Dynamics of Machinery course for mechanical engineering. This semester, two student teams coordinated efforts to provide prosthetics to a middle school drummer born without hands.

“When they shared their original design plan with me, I told them they had a one-in-a-million chance of making it work – but they rose to the challenge and proved me wrong,” Canfield said. “This ended up becoming a terrific project that we are all excited about.”

This one-in-a-million design means Aubrey Sauvie, who plays the snare drum in her middle school band in Murfreesboro, can achieve the same sound quality and volume as the other drummers she plays alongside.

Like everything from writing to brushing her hair, Sauvie has learned to adapt her own way of doing things – but when it came to her music, she needed a bit of assistance with the acoustics.

Project team member Andre Braden said, “This is the first time I’ve taken what I’ve learned in the classroom and truly applied it in a way to impact someone for a lifetime.”

Teammate Luis G. Flores-Moreno agreed, saying, “Doing what we’ve just done really makes us understand what engineering is about.”

But the team’s cooperation was hard-won. In fact, it was competition that influenced the two teams to come together in the first place.

“I wanted to work on this project. I’m well versed in 3D printing, and I knew I could create a high-caliber prosthetic with a level of detail no one else in class could,” said Branson Blaylock.

When the team he was leading wasn’t selected for the project, Blaylock didn’t take no for an answer. He and his team approached Canfield and the other team to persuade them to agree to a merger.

“We all sat down with each other and set our foundation for working together from day one. The advantage to having two separate teams coming together meant it was much easier to work in subgroups and distribute specific tasks. We worked as a well-oiled machine,” said Zak Henson, who became co-leader of the combined group along with Blaylock.

One subgroup served as a liaison between the project group as a whole and Sauvie and her family.

“We were able to spend some time with her, observing how she interacts with objects in her day-to-day life, and we found that she’s so smart, quick-witted and capable despite not having hands. Her family welcomed us in, and she was such a joy to be around,” said Addie Johnson, who was on that liaison subgroup.

That’s when the team truly realized they needed to set aside personal desires for the power of collaboration.

“That’s when we realized that this is and always has been way more important than just a grade,” Henson said.

Having female engineering students on the liaison subgroup also turned out to be a significant advantage.

“She opened up to us and wanted to talk about makeup and clothes – you know, things that many typical pre-teen girls are interested in,” said Micah Page, who served on the liaison group with Johnson, Flores-Moreno, and Elijah Sayre.

“Without Addie and Micah, we wouldn’t have been able to bond with her as much as we did. It still would have been a great project, but she just wouldn’t have been able to open up to me like she did to them. Because of them, we were all able to provide our best,” said Sayre.

That same feminine touch also came in handy for adding design flourishes. For instance, the cords for adjusting the tightness of the prosthetics – which are not interchangeable and are therefore each specifically designed models – are made from bright pink 3D printing filaments.

As for the designs themselves, everything but the tightening grips is made completely by 3D printing using a durable, yet flexible material. Their honeycombed pattern makes them more comfortable for Sauvie to wear in varying temperatures, and the adjustability means they will still be useful to her as she continues to grow. The drumstick attachments are made from the same material. They slide snuggly into the holding loops but can vibrate and reverberate enough to achieve a robust sound when hit against the drum.

“I expected them to 3D print composite casts and use the casts to create the products. That’s typically how that process works. I didn’t expect them to create almost the entire products from 3D printing, but they ended up being great working designs,” Canfield said.

Blaylock said he knew early in the design process that trying to create the prosthetics from composite casts wouldn’t yield the flexibility the products needed to have.

“The products we created will literally last a lifetime. They can withstand temperatures up to 540 degrees and as low as -11 degrees Fahrenheit. We performed every stress test we could think of; we threw them against the wall; we jumped on them. They still held up,” he said.

What were the group’s overall takeaways?

“Everyone in this group used our own experiences and strengths to contribute to its overall success,” said team member Michael Cantrell.

“It all came down to relatability and reliability. We had to trust ourselves and each other, and by doing that, we were able to create something much greater than any one of us could have achieved alone,” teammate Zac Fisher added.

Some group members also said they hope to continue working with Sauvie on future engineering projects, creating different attachments that can help her more easily perform other tasks with the prosthetics.