INTERFACE BETWEEN CAD AND RAPID PROTOTYPING SYSTEMS .1. A STUDY OF EXISTING INTERFACES

Rapid prototyping processes produce parts layer by layer directly from the CAD model. The processes proceed by first slicing the geometric m odel of a part into layers. A standard interface is necessary to conve y varied geometric descriptions from numerous CAD packages to Rapid Pr ototyping (RP) systems. The STL (STereoLithography) format is the most commonly used interface for this purpose. Unfortunately, it is an app roximate model and is frequently not robust. Therefore, other interfac es are proposed to be used for RP systems. This paper, Part 1, will di scuss several existing interfaces including the STL file for the RP sy stems. The strengths and weaknesses of these formats when used for RP systems are analysed. Furthermore, a new improved format is proposed b y the authors in Part 2. In that paper, the design considerations and data structure of the new format are introduced.