Numerical and analytical model used for building a Hexastorm. The analytical model is contained in analytical.py The numerical model is contained in simulation.py. The article where the model and the technology for the Hexastorm is outlined is available here. A presentation on the technology is available here. The Zemax lens is contained in zmax_49332ink.zmx. Installation info for Rayopt is available here. Note that the glass and stock catalogs need to be grabbed from the Windows installation to parse the lens data. The program also works under Linux.

Official site
Hackaday page
Reprap article