An Integrated Rapid Prototyping and Vacuum Casting System for Medical Applications

Abstract

Evaluation of products in the design stage has played a critical role in product development. Methods to build functional prototypes have been a deciding factor for designverification. As an emerging technology, rapid prototyping is revolutionizingthe process of building prototypes. However, material limitations and highcosts call for further expansion of this technology focusing on batch productionof prototypes with material options.<p>Recognizing the challenge to produce multiple prototypes, this thesisresearch aims to integrate three state-of-the-art technologies: 3D solid modeling, rapid prototyping, and vacuum casting. A system architecture combining hardwareand computer software is designed and implemented. <p>The system utilizes computergraphics to construct a 3D model of an object through visualitzion. A softwaresystem, Maestro, processes a CAD file, generates support structures, and creates slice data to build prototypes by a stereolithography process. Thebuilt part serves as a master pattern for creation of a silicone rubber mold in a vacuum environment. This vacuum environment creates a material flow ratethat ensures replicas with superior quality in regards to surface finish anddimensional accuracy. This mold is then used to cast multiple replicas ofthe master pattern.<p>The unique contribution of this research is the application of thedeveloped system to meet a specific need in medical research - an effort torestore sight in blind individuals by implanting electordes in the visualcortex. Six replcas of a monkey skull are produced for surgeions to practicesurgical procedures. Image data obtained from CT scans of a mondkey head are successfully used to contruct a 3D solid model to fabricate a batch of six functional prototypes. The superior quality of these replicas hasoffered a unique opportunity for exploratory surgery in efforts to restoresight.