I started working on S3l3ctor during the summer of 2018. The project aimed to create a simple multimaterial module using just two stepper motors and commercially available electronics. I collaborated with a team of 4 in the design, software development, and testing of S3l3ctor. The project was modeled in Solidworks and Fusion 360, and software to interact with the Klipper 3d printer firmware was written in Python.
The lower stepper motor (left) drives the hobbed gears that push the filament into and out of the printer extruder, while the upper motor (right) controls which filament is pressed into the drive gears. This allows many filaments to be controlled by just two motors.
The red box houses filament runout sensors, which would detect if any color runs out of filament.
Cross section view of main body, showing the interaction between drive gear and spider.
The mushroom-shaped "splitter" took several major design revisions and minor tweaks to perfect its geometry. It needed to be both compact and minimize filament bend radius to help reduce jams. I tested multiple designs before eventually settling on the hexagonal mushroom.
Above: designs considered for the "splitter" -- the Christmas tree, the scraper, the Y, and the mushroom.
Final hexagonal splitter design printed.
S3l3ctor mounted on a printer for testing.
First moves of S3l3ctor under its own power
S3l3ctor demonstrating its tool change G-Code macro
