Mechanical + embedded systems

Recycled-plastic pelletizer

A filament-cutting pelletizer with a stepper feeder, DC cutter motor, and RP2040 controller.

Tools
RP2040 · C/C++ · CAD · Motor control
Blueprint illustration of a pelletizer with a filament spool, control panel, cutter, and supporting frame.
Pelletizer blueprint.

Problem & constraints

Our team built a machine to cut plastic filament into pellets for use in a recycling workflow.

The feeder, cutter, sensors, and controls had to fit in a compact assembly, stay accessible for maintenance, and handle interruptions on a student-project budget.

Design & approach

I connected the RP2040 controller, stepper feeder, DC cutter motor, and encoder feedback. The firmware separates motor control, sensors, the display, storage, and operating states into modules.

The controller handles running, pauses, filament insertion, runout, jam clearing, and errors. An emergency-stop event stops the motor and puts the controller into an error state.

Files & documentation

Results

We assembled the prototype and published CAD, wiring diagrams, a bill of materials, and firmware. The repository includes photos of the machine and cut pellets.

Supervised by Dr. Alessia Romani at FAST Lab, Western University. The team’s design draws inspiration from Teaching Tech.