Synthesis of the digital mock-up system for heterogeneous CAD assembly

Abstract

Many collaborators are involved in design processes of cars, ships, aircrafts, machine tools, etc. Instead of a single CAD source. several CAD systems are used to design such complex products in the distributed design environment. There are many mismatches and interferences due to designers' faults as well as several kinds of CAD systems. Digital mock-up (DMU) system, a tool to build a virtual mock-up in the design stage, has been used to prevent the interferences and mismatches during precision design processes. In this paper, a heterogeneous CAD assembly method to construct the DMU system is proposed through an XML and the lightweight CAD file. The XML data contain hierarchy of heterogeneous CAD assemblies. STEP PDM schema is applied to construct the XML data. The lightweight CAD file produced from a CAD file through ACIS kernel and InterOp includes not only mesh and B-Rep data, but also topological data. They are used to visualize CAD data and to verify dimensions of the parts. Developed system is executable on a desktop computer. It does not require commercial CAD systems to visualize 3D assembly data. Assembly of heterogeneous CAD models has been conducted to verify the effectiveness of the developed DMU system on the Internet.