基于特征设计的CAD系统

介绍基于Ｐｒｏ／ＥｎｇｉｎｅｅｒＣＡＤ系统，借助于Ｐｒｏ／Ｄｅｖｅｌｏｐ开展工具二次开发的基于特征设计的ＣＡＤ系统，该系统操作简单方便设计效率高，可方便地对特征增加附加信息，为后续过程提供了丰富的信息，便于ＣＡＤ与后续过程的信息集成和功能集成，提出广义特征概念，为基于广义特征建立产品集约信息模型打下了良好的基础。     

CAD／CAM软件技术的现状与发展趋势

该文介绍ＣＡＤ／ＣＡＭ软件技术自６０年代产生以来，已经发展到了第三代。文章从评述ＣＡＤ／ＣＡＭ软件技术的现状入手，分析了ＣＡＤ／ＣＡＭ软件三代系统的特点和微机ＣＡＤ／ＣＡＭ软件技术的发展；指出以主模型技术，并行工程技术、虚拟产品研究为方向的未来ＣＡＤ／ＣＡＭ软件技术的发展趋势；该文还对代表第三代ＣＡＤ／ＣＡＭ软件技术发展水平的Ｐｒｏ／Ｅｎｇｉｎｅｅｒ进行了着重的介绍。     

基于装配的CAD技术

论述产品ＣＡＤ系统中的自顶向下设计方法，指出基于装配的ＣＡＤ技术不仅可以保证实现产品的功能，而且能够充分体现设计者的设计意图，最后阐述该方法与ＣＩＭ哲理、并行工程等的关系。     

ARX开发环境下基于MDT API的二次开发技术

一、引言ＭＤＴ（ＡｕｔｏＣＡＤＭｅｃｈａｎｉｃａｌＤｅｓｋｔｏｐ）是在ＡｕｔｏＣＡＤ基础上开发的通用三维机械ＣＡＤ平台,主要包括机械ＣＡＤ参数化特征造型、曲面造型和装配造型三大部分。当前,以ＭＤＴ作为ＣＡＤ／ＣＡＭ／ＣＡＥ集成系统的一体化解决方案引起了人们的广泛关注。ＭＤＴ建立的机械产品建模可直接完成如下功能：装配干涉检验;零部件质量特性分析;自动生成装配分解图;生成零件工程图;生成部件及产品装配图（区分剖面线,自动完成阶梯剖）;生成产品渲染图;标注装配序号,自动生成ＢＯＭ表。要对零件模型进行有…     

基于Pro/E的产品装配建模系统

本文介绍一个以产品装配模型为中心，基于Ｐｒｏ／Ｅ的产品装配建模系统。该系统在产品装配模型的支持下能有效地提高产品的设计质量，支持产品的并行设计，并且能有效地满足快速多变的产品市场需求     

基于装配关系的CAD并行设计支持系统原型的研究

分析了并行工程的特点以及当前机械ＣＡＤ系统的现状，提出在并行设计过程中根据产品的装配关系管理设计参数和几何模型。文中建立了一个数据模型描述机械产品零／部件的层次关系，装配关系以及参数间的继承与依存关系，最后讨论了基于此模型的并行设计支持系统的功能和工作原理。     

基地Pro／E的产品装配建模系统

本文介绍一个以产品装配模型为中心，基于Ｐｒｏ／Ｅ的产品装配建模系统。该系统在产品装配模型的支持下能有效地提高产品的设计质量，支持产品的并行设计，并且能有效地满足快速多变的产品市场需求。     

装配序列规划研究综述

装配序列规划是机器人智能装配中的一项重要研究课题，也是ＣＡＤ／ＣＡＭ以及ＣＩＭＳ研究的一个重要组成部分，涉及计算机，人工智能，自动化，机器人和机械工程等领域，本文对机械装配序列规划研究的历史和技术现状进行了综述。     

产品数据管理系统HEC-PDM

一、引言目前实现ＣＡＤ／ＣＡＭ过程中的管理操作主要依靠操作系统提供的有限的功能,阻碍了设计自动化程度的进一步提高,甚至开始出现混乱。传统的ＣＡＤ／ＣＡＭ过程管理方面存在如下问题。在ＣＡＤ／ＣＡＭ用户管理方面,每个用户仅对自己的产品数据拥有访问权限,与同组其他人员交换数据时有许多不便。另外,在数据的集中管理和数据的安全性之间存在着冲突。在设计图纸管理方面,不能提供能够显示每个产品中的零件之间的树型装配关系的目录或视图,无法取得对整个产品装配关系的直观的了解。当需要调出一张图纸时,不仅难以查找由他人…     

基于模板的自顶向下并行装配设计

在分析产品设计系统的装配功能的基础上,提出了一个并行装配设计模式及装配模板与模板实例化的概念;在处理装配约束的虚拟表示与实例表示概念,使得系统具有了支持自顶向下和自底向上２种设计方法的能力。该方法已被成功地应用于参数化特征造型系统ＺＤ－ＭＣＡＤＩＩ中,证明了基于装配模板基础上的装配设计方法法能在零件设计级上有效地支持并行设计。     

An expert system for assembly based on Axiomatic Design principles

Increasing demands for lower cost of goods, due to international competition, has developed a new area of rationalization for increased productivity which can be achieved by applying new radical methods of production principles. Design for Assembly (DFA) is one of such methods that should be considered in the early design stage in order to cope with the increasing demands of lower cost, improved working environment, and higher wages. When Axiomatic Design (AD) is implemented with DFA in an intelligent way, a new area of design concepts would be realized. This study examines some elements of intelligent design systems to assess manufacturability of a product through the development of a knowledge based expert system for assembly (KBESA). The knowledge base has been acquired from DFA along with AD concepts with emphasis on the conceptual design stage where the structure of the product as a whole is considered. These concepts have been implemented in a case study illustrating its applicability.     

虚拟环境下面向装配的设计系统的研究

虚拟环境下面向装配的设计,是一种集成虚拟现实技术和装配性评价的交叉学科研究,文中提出了一个虚拟环境下面 向装配的设计系统VirDFA(Virtual Design For Assembly)的体系结构,首先描述了虚拟人工实时拆卸的过程,着重研究在实现虚拟人工拆卸过程中,需要解决的装配体物性建模、虚拟环境下装配约束的动态管理及装配序列/路径的自动记录等关键技术,其次,从面向产品结构和装配工艺过程两方面的再设计角度,构建了装配性评价体系,提出了定量的装配效率模型和装配复杂度指标模型。并从装配成本的角度来评价产品的装配性优劣,为产品和装配工艺规划的再设计提供了依据。     

Web环境下面向装配的设计系统的研究

提出了基于Web的面向装配的设计系统集成框架,设计了DFA的分析流程和评价体系,并采用Java和Web技术建立了基于网络的WebDFA原型系统．该系统为异地环境下的设计人员提供了产品装配分析和评价手段,最后通过实例验证了系统的有效性．     

A hierarchical approach on assembly sequence planning and optimal sequences analyzing

Assembly sequence planning (ASP) is a critical technology that bridges product design and realization. Deriving and fulfilling of the assembly precedence relations (APRs) are the essential points in assembly sequences reasoning. In this paper, focusing on APRs reasoning, ASP, and optimizing, a hierarchical ASP approach is proposed and its key technologies are studied systematically. APR inferring and the optimal sequences searching algorithms are designed and realized in an integrated software prototype system. The system can find out the geometric APRs correctly and completely based on the assembly CAD model. Combined with the process APRs, the geometric and engineering feasible assembly sequences can be inferred out automatically. Furthermore, an algorithm is designed by which optimal assembly sequences can be calculated out from the immense geometric and engineering feasible assembly sequences. The case study demonstrates that the approach and its algorithms may provide significant assistance in finding the optimal ASP and improving product assembling.     

A framework for automatic DFA system development

Deisgn for assembly (DFA) evaluation has proved to be a systematic approach is determining how well a product is designed from an assembly point of view. Proposed here is a framework for automating DFA evaluation procedure, a key step in achieving a concurrent design environment. Five modules required for this development are: assembly sequence generation; assembly features extraction; assembly code and other necessary operations generation; data manipulation and computation; and re-design suggestion. Partial implementation (linking DFA evaluation procedure with a feature based CAD system) of the framework is also presented.     

An assembly oriented design framework for product structure engineering and assembly sequence planning

The paper describes a novel framework for an assembly-oriented design (AOD) approach as a new functional product lifecycle management (PLM) strategy, by considering product design and assembly sequence planning phases concurrently. Integration issues of product life cycle into the product development process have received much attention over the last two decades, especially at the detailed design stage. The main objective of the research is to define assembly sequence into preliminary design stages by introducing and applying assembly process knowledge in order to provide an assembly context knowledge to support life-oriented product development process, particularly for product structuring. The proposed framework highlights a novel algorithm based on a mathematical model integrating boundary conditions related to DFA rules, engineering decisions for assembly sequence and the product structure definition. This framework has been implemented in a new system called PEGASUS considered as an AOD module for a PLM system. A case study of applying the framework to a catalytic-converter and diesel particulate filter sub-system, belonging to an exhaust system from an industrial automotive supplier, is introduced to illustrate the efficiency of the proposed AOD methodology.     

On a system of understanding assembly illustrations in an assembly manual

This paper presents an assembly illustration understanding system. The system is eventually expected to be applied to a robot which specializes in automated mechanical assembly. Assembly illustrations in an assembly manual usually have two features: 1) In addition to the figures corresponding to mechanical parts, several special line-drawings referred to as auxiliary lines in this paper are often employed for the visualization of the assembly relations among mechanical parts; 2) The assembly illustrations in an assembly manual are disposed sequentially so that the subgoal of an assembly illustration will definitely appear in its succeeding illustrations as an assemblage. Both features are important clues to the analysis and understanding of assembly illustrations. By extracting the auxiliary lines, the system recognizes assembly relations among mechanical parts, and the 3D shape of the mechanical parts as well. Moreover, based on the assembly relations, it conjectures the structural details of mechanical parts such as insertion holes which are usually invisible. After that, it characterizes the appearance of the completed assemblage described by the current illustration. The system finally verifies the result by matching with the figures in a succeeding illustration in which the completed assemblage is given as a subpart.     

公理化设计与DFA集成的产品信息模型

在公理化设计理论的基础上，讨论了产品设计过程中功能要求的分解以及从功能域向结构域的曲折映射过程；建立了产品功能一结构层次模型和面向装配设计的产品信息模型．该产品信息模型不仅能够描述产品的层次结构信息，而且能够描述零部件之间的装配关系信息，能够实现CAD／CAE／CAPP/CAM的信息集成，为产品并行开发过程的信息集成打下良好的基础．以发动机减速器为例，对产品的功能树、结构树以及装配模型和装配关联矩阵的形成进行了说明。     

基于Web 的飞机装配可视化系统研究

针对目前国内航空制造企业飞机装配生产中所存在的装配质量与效率偏 低、生产管理水平不高等问题,面向装配车间实际生产过程,设计开发了基于B/S 结构的飞 机装配可视化系统。首先,构建车间单一产品数据源信息模型,为不同角色成员开发相应功 能模块;然后,使用DELMIA 仿真装配过程,输出可视化文件;其次,使用ActiveX 技术 实现装配动画页面内的三维交互。最后,以某型号大型飞机舱门作为对象,集成验证了该系 统的可行性与实用性。     

Pro/Engineer中装配仿真的实现方法

装配仿真能实时检测和改进产品的可装配性.提出一种可以实现零件在装配路径上进行连续运动的装配仿真方法.在装配体的基准零件中利用草绘工具规划出装配路径,在将要装配到基准零件上的零件中定义装配基准点.利用Mechanism模块的槽从动机构将装配路径定义为槽曲线,将装配基准点定义为从动机构点.根据槽曲线的空间形态定义伺服电动机即可驱动零件实现装配过程仿真.利用"回放"命令还可以重新演示装配过程以及进行实时干涉检测.