Open Architecture Of 3D CAD Geometry Engine And Application Verification

The digital design of industrial products relies on 3D CAD software,while CAD software such as Pro/E and UG require the support of 3D CAD geometry engines.At present,3D CAD geometry engines under companies such as Siemens in Germany,Spatial in the United States,and Dassault in France dominate the main market,granting commercial authorization to users and restricting open interfaces,which restricts the development of CAD industrial software in China.Designing an open architecture for 3D CAD geometry engines can enable more researchers and developers in related fields to participate in the implementation,optimization,and application of geometry engines,promoting the openness and development of CAD systems.This work is supported by the national key research and development project"Construction of 3D CAD Geometry Engine and R&D Platform".It is a sub project of"Construction of 3D CAD Geometry Engine Collaborative R&D Platform",aiming to design an open architecture of geometry engine that supports multi role collaborative participation in research and development.This article describes the development process and functional domain of 3D CAD applications and geometry engines,and analyzes the research significance of open architecture based on the current development status of CAD in China.Based on the analysis of mainstream 3D CAD geometry engines,an open architecture of geometry engines supporting multi role collaborative research and development is proposed,which is divided into two layers:kernel architecture and application architecture.The main tasks surrounding the open architecture of the 3D CAD geometry engine include:(1)Describe the extension and application methods supported by the kernel architecture,divide it into seven kernel modules:basic class library,geometric representation,topological representation,model calculation,discretization,data exchange,and visualization.Discuss key issues such as data structure design,function interface design,extension methods,and module interoperability.(2)Describe the extension and application methods supported by the application architecture,divide it into four application modules:data management,view management,event management,and feature modeling,and four application deployment management functions:module configuration,module deployment,version management,and interface testing.Develop an interface specification applicable to the geometry engine collaborative research and development platform,and specify the naming method,design principles,and testing requirements of the interface.(3)Build 3D CAD applications based on the extension and application methods of open architecture,and verify that the open architecture can support the implementation,optimization,and application of geometry engines.For the needs of CAD model preview and editing,the surface subdivision algorithm of pipeline model and the direct editing algorithm of model are studied,and the 3D CAD pipeline application based on surface subdivision algorithm,the 3D CAD model editing application based on direct editing algorithm and the 3D spatial interactive evolutionary design system based on genetic algorithm are built respectively based on the open architecture.