ME Students Designed Apple Processing Machines for 'Mrs. Smith'

Just how much force does it take to slice a Granny Smith? How about a Fuji? These are questions fall semester students in ME 141: Mechanical Design found themselves asking and answering in order to successfully complete their final projects: to develop a machine that would core and slice apples and place them in a container “for further processing.”

Their machines, commissioned by “Mrs. Amanda Smith” (aka Professor of the Practice Linda Franzoni) in order to help meet the Thanksgiving demand for apple pie, had to be powered by the turn of a crank and/or stored potential energy in the form of pre-loaded springs or weights, for example.

“No electrical energy is allowed,” the project instructions read. “No motors. All human motion must be in the form of rotary motion because ultimately your machine (if successful) will be driven by electric motors and used for production. This machine is only a prototype. You may not touch the apple once it has been loaded in the machine. You may turn cranks, period.”

The machines were also required to move the apple by at least one foot both before and after cutting.

“The project’s focus rested on building mechanical components and picking the right component to do the job: power screws, gears, shafts,” Franzoni said. In past years, students in the course, which is a “prequel” to the capstone design course ME 160: Mechanical Systems Design, had created basketball-dunking robots involving a strong focus on electronic components, she noted.

Franzoni provided each student team with a standard, metal apple corer/slicer kitchen gadget and a receptacle. The students purchased all other elements of their designs with a maximum budget of $200.

Among the final products students presented on Dec. 6 and 7 was “The Applepult,” a large, catapult-inspired slicing machine built by students Shaina Johnson, Arthur Fischer-Zernin, Dan McCartt and Gideon Weinerth.

The $140 machine included a black wooden frame, AC tubing, duct tape, a 20-pound weight and boat cable. After one team member secured the apple onto a rotating arm, another operated a crank that released the weight, held at the end of the boat cable. The dropping weight then slammed the apple into the corer, sending the slices sans core down the AC tubing and into a bowl.

“The rotating arm and falling weight makes a big noise, which we thought was good for our project,” the students said.

A second group, including Joe Goo, Tiffany Hui, Mark Loughry and Edison Zang, presented their rather economical, $65 design based on a lazy susan. The apple was first spun on the susan, and then slowly cranked through the corer/slicer. Once the slices dropped into a wheeled bowl, they were again cranked up a short incline.

The team said their first test of the design resulted in “catastrophic failure,” noting that it might have been more appropriate for cutting a soft tomato than a crisp apple. The students solved the problem with the addition of numerous bolts.

Jay Bush, Beth Vasievich, Eric Gellar and Lian Huang showed up the rest of the class with their design, including a sheet metal frame and hand-crank operated neoprene conveyor belt.

“A lot of you said metal was too expensive,” the students said. “We proved it wasn’t.” Their machine came in at a cost of $159.47.