BURLINGTON – “It’s hard to make an arm,” said Nathan Ruhlman, seventh grader at Turrentine Middle School.
He would know. Nathan spent the past couple of weeks researching, designing and building a prosthetic arm with partner Ty’Rek Davis in Katie Zimmerman’s science, technology engineering and mathematics class.
Zimmerman’s two classes had to get a lot of background research in before they could dive into the project. They learned a lot about how the muscles in the human arm work and about prosthetics, and they even looked at how NASA built the robotic arm for the Curiosity rover on Mars.
Of course, the STEM classes could not work with titanium. Ruhlman and Davis worked with different sizes of PVC pipe, clear plastic tubing, pipe cleaners, straws and, of course, duct tape.
Emani Jefferies and Marco Bruno-Ruiz had paper towel tubes split down the middle and bound together with duct tape.
While they did not have to stay within a budget, students did keep a tally of the cost of their materials, Zimmerman said.
The test of the arms was lifting an empty plastic cup from the table with the arm attached to their shoulders.
The students had fun putting it together, but all faced frustration trying to get the finer points to work.
Ty’Rek was hanging his prosthetic from his shoulder with a loop of plastic tubing going around his neck. The attachment worked all right, but the pipe-cleaner-and-plastic straw fingers did not do as well.
“All I know is I can knock the cup over,” Ty’Rek said.
He ended up taking the straws off the pipe cleaners and experimenting with what shapes he could bend them into to get a grip on the cup.
Aryanna Baldwin and Timajawon Burton used cardboard tubes for their arm, but attaching it to Timajawon’s shoulder was tricky.
Timajawon said there were no good materials for the job. The cardboard tubes were too narrow to go around his shoulder, and the wooden blocks would not bend around his arm.
Frustration is part of the lesson, Zimmerman said. It is important for her students to learn failure is not the end, but the time to rethink things and learn something.
And what did they learn?
“It’s hard to make an arm.”