共查询到19条相似文献,搜索用时 140 毫秒
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本文以Sigraph-design为支持软件,运用面向对象的建模原理,研究活塞头部件中各个零件的元对象模型,以其装配形式进行对象类的形状定义,建立基于事物特性表的对象类变型产品模型。通过活塞头部件的对象类变型产品模型的属性的不同取值得到重用状态下的一个个实例对象,从而有效地表达了具有相同功能、相同结构,但物理形状不同的一类活塞头部件。 相似文献
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企业产品三维模型数据库的构建,是实现大规模定制设计和快速响应设计的基础。为了满足快速构建企业产品资源库的需求,提出了一种基于三维设计平台的企业零部件库参数化建模方法。该方法以三维设计软件UG NX为开发平台,基于NX/Open开发产品三维零部件库。基于层次性参数化建模方法,提出利用主模型技术和自顶向下的方法实现产品的参数化建模及变型设计,实现了零部件和装配体的参数化建模。结合数控机床快速响应设计系统中刀具库设计开发的实例,给出企业零部件库的建库流程,表明基于主模型的层次性参数化建库方法是企业产品资源库建立 相似文献
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本文在分析比较参数化设计方法的基础上,研究了基于特征的参数设计方法,它采用模具的装配模型和零件特征模型表达模具的装配关系,模具结构和加工过程,用尺寸驱动的几何模型确定特征的形状尺寸和定位尺寸,这种方法的优点是模具结构的描述简单,直观,同时也有助于实现模具CAD/CAM系统的一体化。 相似文献
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随着企业快速响应市场的需要,参数化技术广泛应用于产品设计研发中。基于三维CAD系统的参数化技术主要考虑的是产品的基本尺寸设计,很少考虑尺寸公差,而尺寸公差又是产品的重要设计指标,所以为了解决尺寸公差参数化设计问题,对零件参数化模型中的尺寸公差信息表达、提取与标注方法进行了研究,提出了一种基于参数化技术的零件尺寸公差设计方法。利用VC++,对三维CAD软件SolidWorks进行二次开发,开发出了基于SolidWorks的零件尺寸与尺寸公差集成参数化设计插件。以轴类零件为例,对提出的方法和开发的插件进行了应用验证。 相似文献
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基于产品动态模型的智能快速响应设计理论和方法研究 总被引:9,自引:1,他引:8
文中将产品动态模型应用于快速响应变型设计中,研究了快速响应变型设计智能化理论和方法,提出了采用规则推理和实例推理相结合的混合推理策略;并针对设计的过程性,将变型设计分为概念变型设计、装配变型设计和产品定义变型设计;最后分析了基于产品动态模型的智能变型设计过程。 相似文献
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通过研究和分析UG二次开发方法以及三维零件参数化设计方法,提出了一种基于三维零件模型的参数化程序设计方法.该方法通过UG/Open二次开发工具在VC++环境下设计用户界面,并利用MFC结合SQL Server 2005数据库开发应用程序,以飞艇艇体为例建立了参数数据库管理系统,实现了零件的参数化设计.基于该方法对飞艇其它部件进行建模,给出了飞艇的参数化模型,表明了设计方法的可行性. 相似文献
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提出基于功能结构一结构视图模型的零件族建模方法,将零件变型设计的对象层次定义到有一定工程语义、表达工程功能的结构,将零件描述为由功能结构以一定的组合关系构成的可扩展网络.组成零件的功能结构通过施加空间布局约束和拼接约束建立零件族模型.通过修改参数尺寸可以实现零件大小的变化;通过对功能结构的修改或替换达到零件实例结构的变型和变异;通过提高零件变型对象的层次实现零件功能结构的变异. 相似文献
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随着CAD/CAM技术的发展,整个产品的设计、虚拟制造和数字化样机都可在计算机中完成,使得包含大量数据的复杂装配体(即大装配体)的设计成为产品设计过程中的必需元素。由于大装配体模型数据量庞大,在普通PC机中处理极为不便,为了提高处理速度,需要对大装配体模型进行简化。在不改变装配模型格式和整体外观的前提下,提出了两种装配体模型的轻量化方案:1)从装配体中删除隐藏的零部件;2)从装配体中删除隐藏的特征。零件和特征的可见性是通过从多个视点预渲染装配模型,然后读取渲染缓冲区的结果并进行分析而得到。实验结果证实该算法能在不改变CAD模型格式和外观的前提下准确地删除装配体中的隐藏零件和特征。 相似文献
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为了进行快速的变型设计,需要一个合理的产品结构设计模型,据此提出一种基于产品基因的新的变型设计方法。建立了支持变型设计的产品基因模型及其操作序列,并由此构建出产品优化模型。运用人工免疫算法得到了产品变型设计的最终优化结果。最后结合一种典型的机电产品验证了文中提出方法的合理性和有效性,为产品变型设计理论提供了另一种结构设计方法和优化方法。 相似文献
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面向装配工序交叉的虚拟装配工艺信息模型 总被引:5,自引:1,他引:4
虚拟装配工艺规划中目前大都采用装配顺序描述装配过程,但尚无法表达装配工序交叉和设计中的安装布置'捌整等问题.考虑设计阶段和制造阶段的装配要求,建立了基于装配任务的装配工艺信息模型.该模型以多层次的装配进程表达产品装配工艺过程,通过任务对象的交叉安装表达工序交叉和安装布置凋整,并给出了装配调整策略;针对冗余装配任务提出了装配任务合并方法.最后通过实例验证了文中模型的正确性和有效性. 相似文献
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Microdevice assembly knowledge is dispersed in different product development phases, such as assembly design, assembly simulation and assembly process, and a lot of essential knowledge is implicit and heterogeneous. It is difficult for researchers and computer-aided systems to share and reuse different assembly knowledge quickly and accurately, leading to inefficient and inaccurate assembly process planning. To integrate and structurally represent the assembly design knowledge, assembly simulation knowledge and assembly process knowledge of microdevice, this paper proposes a hierarchical assembly knowledge representation framework and develops a microdevice assembly ontology. There are four layers in the framework, including the organizational structure, the structural relationship, the assembly accuracy, and the process characteristics. The assembly design knowledge that is integrated involves the basic properties of the assembly object as well as the spatial, mating, and assembly relationship, etc. Assembly simulation knowledge refers to the permissible range of assembly force and contact force. Knowledge of assembly processes comprises assembly sequence and operating method of the part. The microdevice assembly ontology is developed based on METHONTOLOGY, and implemented with Protégé. The corresponding SWRL rules have been established to inference the implicit knowledge in assembly design. An ignition target assembly knowledge model based on the microdevice assembly ontology is constructed. In the assembly task of the ignition target, engineers can quickly and accurately access the required assembly knowledge from the ignition target assembly knowledge model, thus verifying the integrity and validity of the microdevice assembly ontology. 相似文献
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基于Cult3D的产品网络化拼装定制与展示技术研究 总被引:5,自引:0,他引:5
论文在分析已有的网络化定制设计特点的基础上,提出了一种新的产品网络化拼装定制与展示技术。探讨了该技术的实现途径与流程,并对基于形态的部件级拼装定制这一关键技术进行了详细研究。在此研究的基础上,利用ASP、网络数据库及Cult3D技术构建了产品网络化拼装定制与展示系统的框架并进行了应用。 相似文献
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基于符号的装配建模方法研究 总被引:4,自引:1,他引:4
在以装配符号的定义实现产品装配设计语义抽象表达的基础上,对产品装配建模过程中装配语义的表达、装配语义与装配约束的转化及维护技术进行研究.提出基于装配符号的约束规则集描述,实现产品装配设计信息的传递,并采用装配符号关系图对产品装配设计语义与约束进行动态维护.通过产品装配信息从抽象到具体、从模糊到精确的转化,实现产品装配设计系统对抽象、模糊、动态关联的产品装配设计信息的表达、传递和维护. 相似文献
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A PDES/STEP-based model and system for concurrent integrated design and assembly planning 总被引:9,自引:0,他引:9
Product data exchange and interfacing between different CAD/CAM systems are of great importance to the development of concurrent integrated design environments and computer integrated manufacturing systems. This paper presents a STEP-based method and system for concurrent integrated design and assembly planning. An integrated object model for mechanical systems and assemblies is first defined by a hierarchy of structure, geometry and feature. The structure is represented as a component-connector or joint multi-level graph with both hierarchical functional and assembly relations. These hierarchical relation models are then used for uniformly describing their causal relations both for assembly level and feature based single part level. The generic product assembly model is organized according to STEP, using mostly the entities of integrated resources and partly self-defined entities, which are necessary for design and assembly planning. Based on the generic product assembly model, STEP-based strategies and agent concepts are used for agent-based concurrent integration of design and assembly planning. A prototype system, consisting of a CAD system, a product modeling system, an assembly planning system, and an assembly evaluation system is developed, in which product data can be exchanged between these subsystems. Details about the implementation of the system are addressed. The integrated design and assembly planning system can support the introduction of a new product. The results of assembly planning are feedback to the stage of assembly design to improve on the design. A case study is carried out for assembly-oriented design of a gearbox, to illustrate the proposed approach and to validate the developed system. 相似文献
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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. 相似文献