An XML Implementation for Data Exchange of Heterogeneous Object Models

Abstract

Heterogeneous objects refer to objects with spatially different material compositions or structures. Tremendous research efforts have been devoted to modelling heterogeneous objects and many heterogeneous object representations have been proposed. Regardless of the diversity of these CAD models, there are needs to transport and exchange the included geometry, topology as well as material distribution between CAD modellers, CAE tools and CAM facilities. In literature and practical applications there have been lots of STEP (STandard for the Exchange of Product model data) based tools and implementations for the exchange of the geometric/topological data. However, there has been only limited research on the data exchange of material distributions. This chapter focuses on an XML implementation for data exchange of heterogeneous CAD models. The proposed heterogeneous CAD model is described by Extensible Markup Language and detailed approaches to represent the voxel based, explicit function based and heterogeneous feature tree based models are described. The idea is to introduce self-descriptive, customised tags/vocabularies to fit the specific needs of material modelling. The structure of the heterogeneous CAD model is specified with XML schemas and related data validations can accordingly be checked to ensure the model correctness. A prototype CAD module is developed to construct XML-based heterogeneous material model, and the XML model is then exported to SolidWorks to test the validity of the proposed approach. Results show the proposed XML based model can facilitate the data exchanges of heterogeneous material distributions.