Distributed Design and Fabrication of Parts with Local Composition Control

Solid Freeform Fabrication (SFF) technologies offer the potential to create parts with local control of the composition (LCC). This work develops the representations, methods, tools and design rules needed to allow for the design and fabrication of parts with locally varying composition. Three Dimensional Printing is used as a prototypical Solid Freeform Fabrication process. The goal is to provide the designer with tools sufficient to allow the designer to create a successful part with “oneway information flow”, that is, flow of information from the designer through the fabrication sequence without iteration. This paper focuses on the post-processing of representations, which includes information on local composition control. Such representations are first rendered as halftone images, in accordance with the digital aspect of Three Dimensional Printing. The boundary geometry information is then reconciled with the interior composition information and machine-specific code is generated to drive a 3-D Printing machine. Demonstration parts with composition that varies from the surface toward the interior of the parts have been fabricated using this technology.