Development of an advisory system for trapped material in rapid prototyping parts

Since the launch of the first commercial system in 1988, rapid prototyping (RP) technology is fast being accepted in the fields of product design and development, tool and die making, and recently, for biomedical applications . Although RP is able to produce objects of any complexities in theory, pro blems such as having material trapped inside parts with hollow features sti ll occur frequently during normal operation. This could result in a distort ed part being built, or the system being damaged. To reduce such occurrence s, the purpose of this project was to develop an application program using the Unigraphics CAD/CAM system, to search automatically for the problematic features in a CAD file, and to provide the necessary modifications or reco mmendations. The initial focus has been on providing solutions for objects produced by stereolithography apparatus (SLA) and selective laser sintering (SLS). Provision has been made through the use of modular programming to a llow more upgrades in future to other RP systems.