Apfelstruder Is a CNC Lathe for Apples, a Pioneer in Fruit Fabrication!

A CNC lathe is a versatile and powerful fabrication tool, and building one can be a rite of passage for many budding engineers. But a team of MIT students took a totally new direction with their approach, giving the world Apfelstruder, a CNC lathe for apples. Seemingly a pun on Apfelstrudel and extruder, the team calls it "a revolutionary new technology in Computational Food Fabrication." And given how few projects exist at the overlap of fruit and machine design, that really is no overstatement.

"By over-engineering the simple task of cutting an apple, we open up a new design space for human-apple interaction,” says the team in their project video, and Apfelstruder, built for MIT's How To Make (Almost) Anything course, certainly is a complex device given its singular purpose. On the physical side, it features laser-cut and 3D-printed parts that allow an apple to be tightly affixed between metal prongs and a 3D-printed gripper, which act as a chuck. Most of the hardware are common 3D printing parts like lead screws and timing belts. And when activated, stepper motors drive the spindle, as well as the cutting tool, providing full control over depth and location of cut.

The software side of the project is just as complex and nuanced as the physical build. “Every apple is unique,” they claim — so to enable the full customization of each soon-to-be-milled fruit, the students developed a UI for digital design of the apple, and used a distributed data flow machine controller (developed by another student in the same course) called Squidworks. Their UI lets a user input physical parameters about the apple (like height and diameter), and then use a drawing tool to create the profile for the machine to cut.

All together, it’s an extremely intricate and exciting system architecture, especially given how specific of a task it’s design for — but perhaps the most notable part of the project is that the team went from ideation to final prototype in just seven days. Working at that speed and complexity is no small task, and luckily the team kept meticulous documentation, so you can deep-dive into their process and timeline on their project page, hosted by The Center for Bits and Atoms. We can only hope the Apfelstrudel is the first of many fruit fabrication projects yet to come!