As part of my work in the UMD Terrapin Works Rapid Prototyping Lab, I started an optical 3D-scanning project with the aim of creating an inexpensive scanning platform capable of producing STL files for 3D printing.
It uses a Raspbery Pi 1, the Pi camera module, a stepper motor driver, and a stepper motor all fed by a 15V brick supply. Here is what a scan of 20 separate images looks like:
This is an ongoing project and is accessible on Github. We are currently writing the software for stitching together STL files.