Video demo here: https://vimeo.com/1063915896/1a0645efcb

We've finished the project, though we're still working on some optimizations to prevent the pulleys from getting stuck. The STL files for our 3D printed parts (pulleys, blue/grey core adapter, and motor mount) have been posted to Hackaday. Here's the editable Onshape file for the pulleys: https://cad.onshape.com/documents/380de83321b66506218ea3fa/w/c4c5e723950741839b369f04/e/5c50764f8d3d2605ba21e744

We'll also post the TinkerCAD links for the 3D parts soon.