Work in progress — nothing here has been built yet. This is the second CAD pass; the first never reached fabrication, but plenty of design thinking carried forward into this one. Enough has been done to validate the premises; not yet enough to build.
An AI-powered LEGO sorting machine — every part vibe Caded with @claude-opus-4.7 using cad-khana. About 140 commits over ten weeks, with several whole-module pivots. Most recently, the scanner's dump mechanism went from a radial cam-and-kicker to a bench-mounted servo.
@restlessronin reads engineering drawings and CAD models but has never drafted a part himself; he sets the concept, flags what's wrong, asks for changes, calls the geometry pivots. The expertise is thin. The output isn't.
System Overview
A feeder drops loose bricks into the singulator, which presents them one at a time to the scanner. The scanner photographs each from four angles, a vision model identifies part and color, and the diverter routes the brick into a bin.
This article covers the CAD: singulator, scanner, diverter. ML, firmware, and the rest of the software will get their own write-ups. We'll open the repo with the first build; this article series is the public record until then.
Singulator
A cylindrical c-channel (an idea from the Basically team) feeds one brick at a time into the scanner, in place of the flat V-channel in RobG's design, where we began.
Scanner
Four cameras sit at the vertices of a regular tetrahedron[1] around the brick, every pair of lens axes 109.47° apart. A 2x2 brick and a 2x2 plate look identical from above; from any other angle, they don't. A central turret indexes bricks one at a time into the scanned volume, then tilts each platform to drop the brick into the diverter below.
Diverter
A hex tower of baskets — a concept from Basically, first adapted to extrusion-only by Cristian Cuevas, reworked here. The central rotating column points its ramp at one basket at a time, and per-floor trap doors decide whether the brick drops there or falls through to the floor below.
The tetrahedral arrangement is original to this build. The singulator and diverter stand on community shoulders. ↩︎
Credits
Concept by @restlessronin. Written by @claude-opus-4.7, who also created the display artifacts.
Thanks to RobG for several DM conversations. Lukas Weick surfaced prior builds we'd missed and championed alternate singulators. Cristian Cuevas gave detailed fabrication advice.
We started from RobG's LEGO sorter and stepped, via the constraint of "extrusion + 3D-prints only," to something close to the Basically LEGO Sorter by LegoSpencer and team.
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