Interfacing Design Code and Simulation Code for Biological Shielding

This project builds on experience in an SBIR phase I project which successfully determined that the particle transport code Geant4 could be applied to the simulation of biological shielding. Among the many lessons learned during phase I was that while the physics and functionality embodied in Geant4 is either already excellent, or clearly extendible as needed, the great lacuna lies in its ability to understand geometries specified by other tools, most notably CAD tools. To this end, while this proposal involves continuing to work with the physics of the program, the main focus is on developing the tools to match the representation systems intrinsic to Geant4 to those used by other tools which generate geometries. Based on discussions with NASA this is by far the most pressing issue for immediate application to space radiation shielding, and is certainly crucial for all commercial applications we envisage as a small business.