An interactive cad environment for heterogeneous object design

Abstract

Traditional computer aided design (CAD) systems assume that the solids under design are homogeneous in material compositions. Recent studies have shown that solids made of heterogeneous materials (multiple materials, functionally graded materials etc.) prevail in some aspects in terms of mechanical, thermal or electrical performances. Most of the traditional CAD systems fail to represent, maintain and visualize such heterogeneous components, and there have been no commercial heterogeneous CAD modelers in the market. This paper proposes a new interactive CAD environment for heterogeneous object design, in which the geometry, topology and material information of a CAD model can be simultaneously manipulated. The functionalities of a heterogeneous CAD modeler are identified first, and a framework for heterogeneous object design is proposed. The issues of data representation, data maintenance (edition and update) and 3D visualizations are discussed. An interactive software package based on this framework - CAD4D is presented and detail examples are illustrated.