【作者】 南风强；

【导师】 张友良； 汪惠芬；

【作者基本信息】 南京理工大学 ， 机械制造及其自动化， 2008， 博士

【摘要】 随着全球市场竞争的日益激烈,产品的设计制造过程由一个企业独自完成发展到具有互补性企业之间的强强联合。装配作为联系产品的设计和后续工艺规划的纽带,它涉及人员多,影响面广。网络协同数字化预装配技术可以使地理上分布于世界各地的设计、工艺以及制造人员参与到产品装配设计、验证过程中来,通过构造跨地域、跨时间的产品装配的数字虚拟仿真与实验空间,使产品的装配活动在计算机内进行虚拟实物复现,可以进行装配过程仿真、装配序列规划、装配公差分析、产品的可装配性验证等分析,为异地协作的不同领域的工程师进行装配设计、规划和分析提供工具支持。本文首先介绍了并行工程、虚拟制造等先进制造技术背景,阐述了网络协同数字化预装配技术的意义。针对网络协同的特点和需求,提出了一个具有可重构、可重用、可扩展、支持多学科人员在网上开展异地协同数字化预装配系统的体系结构。分析了系统的功能模块及组成结构,给出网络环境下数字化预装配系统的工作流程。对产品特征信息进行分类,在研究零件特征的公差信息表示基础上,提出了面向装配精度的产品层次装配模型。该模型分为层次关系层、关联关系层、特征信息层、特征元素层和三角面片层五层,通过建立层内各元素的关系链和层间信息的映射实现产品装配信息的有机结合。研究了CAD零件信息与数字化预装配系统的信息转换方法,给出了数字化预装配环境中产品装配尺寸链的自动寻找和公差分析方法。针对产品装配过程的多样性、复杂性,提出了一种可重构的具有层次结构的数字化预装配环境模型,该模型分为设备层、中间层、零件层三层。对装配环境信息进行分类,给出了模型的形式化表达方法,利用面向对象技术构建了产品的数字化预装配环境。给出了环境中虚拟工装设备模型的数据结构、环境的配置结构,解决了物体的运动仿真、碰撞干涉检测等关键技术。提出了协同数字化预装配环境下产品装配方案综合评价方法。针对产品装配设计与规划活动所涉及到的产品设计(装配设计)、制造(装配工艺)、服务(装配维修)和环境(无污染、易回收)等诸多环节,利用数字化预装配环境,从动态装配过程和静态装配环境两个方面对影响装配的众多因素进行分析和归类,建立了产品装配质量、时间、成本、维修、环境影响模型,给出各评价指标隶属函数和权重的确定方法,利用模糊层次分析法对产品装配方案进行了综合评价。给出了网络协同数字化预装配系统的建模方法,研究了系统运行中的协同技术。针对网络协同数字化预装配的特点,提出了可重组的多Agent协同装配动态组织结构,利用面向对象Petri网对组成系统的各智能Agent进行了行为建模,分析了各Agent之间的交互联系。构建了装配动态组织模型和协同装配过程模型,解决了多Agent之间的通信和协同实时性等实现技术,给出网络环境下产品数字化预装配流程。依据本文提出的协同数字化预装配理论,采用基于组件的程序设计方法开发了一个网络协同数字化预装配系统e-DPAS(e-Digital Pre-Assembly System),并以ⅩⅩⅩⅩ装备的传动系统为对象进行协同装配设计与工艺规划的应用验证。更多还原

【Abstract】 With the increasing competition in global market, the process of product design and manufacture can’t be accomplished by an individual corporation which is instead of teamwork of several cooperative corporations. As a link between product design and process plan, assembly concerns many people and technical fields. Network collaborative digital pre-assembly system can bring the designer, technologists and manufacturers around the world together to take part in the approach of assembly design and verification cooperatively. Through constructing the virtual product simulation and test environment beyond the limit of region and time, the assembly activity can be realized virtually in the computer. The assembly process simulating, assembly sequence planning and assembly tolerance analyzing can all be analyzed under the aid of computer, which support engineers in different places and different fields to work on the assembly design, planning and analysis cooperatively.Based on the analysis of backgrounds of concurrent engineering and virtual manufacturing, the significance of collaborative digital pre-assembly technology is expatiated in this thesis. According to the characterstices and demand of collaborative design, a reconfigurable, reusable and enlargeable system which supports multi-disciplines engineers in different places to carry out a collaborative digital pre-assembly is put forward. The function modules and structure of this system as well as the workflow of digital pre-assembly under the network environment are analyzed.Considering the characteristics of collaborative assembly process, the product feature information is classified. And a precision-oriented digital assembly model is put forward based on the tolerance expression of part feature. This model has five layers, which is made up of hierarchical relation layer, connectivity relation layer, feature information layer, feature element layer and triangle face layer. By establishing a relation chain among the elements in a layer and information mapping among all layers, the product assembly information can be well integrated. Information transformation technology from CAD system to digital assembly system is studied, a method of automatic generation of dimension chains in digital assembly environment is brought out.Based on the diversity and complexity during product assembly process, a reconfigurable product digital assembly environment model is put forward. This model has three layers which are device layer, middle layer and part layer. After categorizing the assembly environment information, the formalized expression of the model is given out and a digital pre-assembly environment is built by the object-oriented technology. The data structure and configure structure of the virtual equipment model in the environment are given, and the key technologies such as the motion simulation and collision detection are broken through.A fuzzy evaluation method of assembly design scheme under digital assembly environment is brought forward. Based on analyzing the characteristics of product assembly designing and planning process including product design (assembly design), manufacture (assembly process), service (assembly maintaining) and environment (pollution abatement, reusable), many factors assembly related are analyzed and classified from dynamic assembly process and static assembly environment under digital assembly environment, and the influence models of assembly quality, time, cost, service and environment are built. The subjection function and weight of each factor are given, and a synthetic evaluation method for product assembly quality, time, cost, service and environment by fuzzy analytical hierarchy process is studied.A method of building a collaborative digital pre-assembly platform is put forward, and the collaborative technology of system is studied. According to the characteristices of collaborative digital pre-assembly, a reconfigurable multi-agent dynamic organization of collaborative assembly is put forward. The action modeling of each intelligent agent that the system composing is build with object oriented-Petri net, and then the communication of each agent is analyzed. The dynamic organization model and process model of collaborative assembly are built, the key technologies of communication and real-time collaboration among multi-agents are studied, and the collaborative digital pre-assembly workflow is also given in this thesis.According to the collaborative digital pre-assembly theories mentioned above, an network collaborative digital pre-assembly system is established by COM technologies. An instance of XXXX gearing system is taken for example to verify the collaborative assembly design and process planning.更多还原