外文翻译---基于特征的,参数化建模系统的CAD CAPP CAM集成系统

附：中英对照外文资料

A Feature-Based, Parametric Modeling System for CAD/CAPP/CAM Integrated System【基于特征的，参数化建模系统的CAD / CAPP / CAM集成系统】——中英文对照

A Feature-Based, Parametric Modeling System for CAD/CAPP/CAM Integrated System

Li Hailong, Han Jianhua, Dong Jinxiang, and Wang Yong

State Key Laboratory of CAD&CG,

Artificial Intelligence Institute of Zhejiang University,

Zhejiang University,Eangzhou, China, 3 10027

Abstract-To shorter product development time, this paper proposed an approach to developing feature based parametric product modeling systems which are suitable for integrated engineering design in CIMS environment. The architecture of

ZD-MCADII and the characteristics of its each module areis managed by introduced in detail. ZD-MCADII's product data an object-oriented database management system OSCAR, and to the standard STEP. For the product model is built according the product design is established on a unified product model, all product data are globally associated in ZD-MCADII. ZD- iMCADI1 provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM.

I. INTRODUCTION

With the increasing pace of technology development and international competition, today's industrial environment is asking for further improvement of design quality and efficiency. As a result, research and commercialization of modern CAD/CAM technology are focusing on the feature- based modeling [I], the parametric design, and even on CIMS(Con1puter Integrated Manufacturing System), to reduce the gap, which traditionally existed between design and manufacturing, and improve the efficiency of product development. So, feature technology and parametric design are playing a more and more important role in the modern CAD systems. The main reason lies in that feature-based design support the integration of CAD, CAPP and CAM systems, and parametric design will reduce product design cycle times dramatically. Solid modeling contributes to fast, efficient, competitive product development, and can simulate the mass properties of physical objects (such as volume, moments of inertia, and center of gravity). In contrast, 3D wireframe and surface models only simulate the shapes of physical objects. So, the most of

CAD/CAM developer choose solid model as geometric model of product.

Ⅱ. OVERVIEW OF ZD-MCADII

ZD-MCADII [2-51 is a product modeling system of Zhejiang developed by

Artificial Intelligence institute is a feature-based parametric modeling system University. It integrated with CAPPKAM systems. The system is based on the achievement of the National 7th five-year-plan project -- "The research of the mechanical product CAD support software for V AX series (UNIX OS)", combined with the National 863 high-tech. Project -- "Product model basedCAD/CAPP/ CAM integrated system" in 8th five-year-plan period.

This paper proposed an approach, which has been applied in our system

ZD-MCADII, to develop feature-based parametric product modeling systems. The basic idea of the development of ZD-MCADII is to present all the product characteristics in a c

rnal representation, to provide the modeling techniques that allow the definition and manipulation of those product characteristics, and to integrate with CAD, CAM systems in CIMS environment.

Parametric modeling of ZD-MCADII can capture design to a intent and allows designer to make substantial changes part or assembly at any time during the design process. Parametric design offers a flexible approach to 3D-parametric modeling. It includes datum aides, such as pattern and group operations, coordinate systems, datum plane, datum curve, and datum point, that help improve designer praductivity. ZD-MCADII's 3D parametric model, 2D parametric and assembly model are associated globally so that any changes in onb or two of these models will cause any other associated models be automatically updated.

ZD-MCADII's sketcher allows designer to build dimension-driven profiles with geometric constraints such as, parallelism, tangency, and colinearity, captured automatically. Designer will be prompted by 'Smart-Line when these geometric constraints emerge. ZD-MCADII's constraints- based modeling allows designer to define equations bi- directionally relating model parameters to external engineering requirements which can then drive model geometry.

Feature-based modeling in ZD-MCADII allows design to include standard design elements in product geometric model and eliminates traditional, time-consuming modeling operations, and it provides various design features to facilitate the product design. ZD-MCADII also allows designer to construct his own feature libraries with user-defined feature provided by ZD-MCADII's feature module. ZD-MCADII's feature editor allows designer to modify a feature on screen by selecting the dimension and entering a ne& 'vahe. User can create a feature from a profile that lacks any constraints or dimensions, and even better, he can add dimensions and constraints later by clicking the feature redefine icon simply. ZD-MCADII is able to convert design feature to manufacture feature used in CAPP and CAM by its feature mapping module.

Ⅲ. THE ARCHITECTURE OF ZD-MCADII

It is we11 known that an open software architecture brings ……plug and play” compatibility and freedom of choice to software applications. So, as an excelient software, it must have an open architecture. From this view point, we pay much attention on its architecture while developing ZD-MCADII.