一种人机特征驱动的驾驶空间布局设计方法

为了强调在概念设计阶段就考虑人机方面的需求,提出了人机特征驱动的产品设计方法,并以汽车驾驶空间布局设计为例进行具体研究.通过引入人机约束概念,建立人机约束模型,并以此为基础选择合适的人机特征评价模型和优化设计方案.在汽车空间布局设计实例中,以关节舒适度作为人机特征,基于实验建立了人机变量与设计参数的关系,完成了人机特征驱动的驾驶空间布局设计模型和系统,并实现了汽车布局设计方案的自动生成,最后对该方法进行了验证.     

面向机械产品布局设计的特征及组件关系表达

将基于特征设计的思想引入到布局设计中,旨在实现概念设计与详细设计之间有效过渡的特征定义和布局组件关系表达。讨论基于特征的产品设计过程,给出相应的定义、分类规则及其表示方法,同时探讨在布局组件关系清晰表达支持下的基于特征的机械产品布局设计建模过程。这为产品计算机辅助概念设计系统的实现提供初步的理论框架。     

基于广义参数化的工程图自动调整技术研究

针对机械产品系列化程度高、小批量、多品种、布局复杂的特点,结合交互式人机结合思想和广义参数化设计技术,将包含参数、标注、文本等不确定的图形变化信息转化为具体的具有精确数值和符号信息的产品几何信息,在详细讨论了基于装配模型的变型设计实现方案的基础上,建立了一个能根据产品参数和结构进行优化调整的自动生成图纸系统,实现了变型设计复杂工程图的后续处理。     

基于数据挖掘的产品概念设计建模研究

在产品概念设计过程中，引入数据挖掘技术和方法，提出了基于数据挖掘的全息虚拟产品概念设计模型，开发了数据挖掘工具，建立了面向产品概念设计方案生成的数据仓库；研究建立决策树算法的数据挖掘模型，以支持度为目标，实现从所建立的机械产品库、设计规则库、领域知识库中挖掘相关数据、信息和知识，从而极大地支持机械产品方案创新设计过程。以机床传动机构设计为例，说明了采用决策树方法的数据挖掘模型来实现机械产品概念设计的功能结构映射过程。     

面向复杂产品系统供应商的价值驱动需求建立

在复杂产品系统开发中,大量的组件和零件被外包给供应商进行设计和生产。为了确保系统能够满足顾客需求,必须将顾客需求逐级演化到系统、组件和零件的设计过程中。为此提出一种价值驱动的面向复杂产品系统供应商的需求建立方法。首先,以顾客需求为出发点,利用多属性效用理论进行价值化建模,并将顾客需求的价值模型逐级演化为系统技术需求的价值模型和组件技术需求的价值模型。同时,为了增强供应商的价值感知,利用价值等价交换的思想将基于效用的价值模型转化为基于货币的价值模型。最后,给出民用飞机研发中引擎供应商需求建立的例子,对方法进行了验证。该方法可为组件供应商在没有明确技术需求的情况下,提供用于概念设计的目标函数,支持尽早开展设计活动,并可方便地拓展到零件级。     

基于语义关联与驱动的产品概念装配模型研究

面向概念设计的装配模型表示是机械产品装配建模技术研究的一个重要问题,现有的基于几何约束关系的CAD系统不能很好地解决这一问题。基于装配语义“三位一体”性给出了面向概念设计的产品装配模型表示方法,提出采用装配语义关联图表达零件之间的装配语义关系,通过装配语义关联图建立起支持概念装配模型的多层次语义关联和基于语义的装配驱动,从而实现机械产品从概念设计出发的自顶向下和从详细设计出发的自底向上的双向设计。     

鞋类产品和谐智能CACD系统研究

针对计算机辅助概念设计的瓶颈问题和关键技术,一方面给出鞋类产品的物元系统表示方法、鞋类产品概念设计中矛盾冲突模型和矛盾冲突解决的可拓工程方法以及可支持鞋类产品概念设计的可拓评价决策模型;另一方面提出面向CAD的CACD的和谐化智能化研制思想,基于SolidWorks系统开发和谐智能计算机辅助鞋类产品概念设计系统,即人机合理分工、人机友好交互、人机智能结合CACD系统。     

鞋类产品和谐智能CACD系统研究

针对计算机辅助概念设计的瓶颈问题和关键技术,一方面给出鞋类产品的物元系统表示方法、鞋类产品概念设计中矛盾冲突模型和矛盾冲突解决的可拓工程方法以及可支持鞋类产品概念设计的可拓评价决策模型;另一方面提出面向CAD的CACD的和谐化智能化研制思想,基于SolidWorks系统开发和谐智能计算机辅助鞋类产品概念设计系统,即人机合理分工、人机友好交互、人机智能结合CACD系统。     

机械产品专利技术方案信息抽取方法

专利因其创新性和实用性的特点成为概念设计的重要知识资源,结构化专利技术方案信息抽取是专利设计原理知识挖掘的基础工作。针对机械产品专利,描述了面向概念设计知识需求的专利技术方案概念模型,将专利技术方案信息抽取任务分解为技术组件抽取和技术关系抽取两部分。研究专利信息抽取知识库建设,利用非确定有限状态自动机识别技术组件,采用专业术语词典进行技术组件语义分析,以框架语义学为理论基础,构建用于技术关系抽取的专利动词语义框架库。提出基于自然语言理解的技术方案信息抽取过程,研究浅层句法分析和语义分析的关键技术,并以美国专利为例进行说明,结果表明该方法可自动获取结构化专利技术方案信息,有助于专利在概念设计中的深入应用。     

计算机辅助机械产品概念设计技术探讨

提出一个支持机械产品“需求分析 概念设计 详细设计”全设计过程的计算机辅助集成设计工具的框架 ,介绍产品设计过程模型 ,面向全生命周期基于广义特征技术的产品信息建模方法、概念设计方法以及设计过程各阶段的集成技术。     

面向方案设计的特征定义及表示方法

将基于特征设计思想引入到方案设计中,提出了旨在实现功能概念与几何构造间有效关联的原型特征和布局模板定义,原型特征定义方案设计的功能需求、概略几何实现方案等产品方案属性及其相互关系;布局模板是原型特征装配的结果,它以草图形式描述方案设计的产品原型特征组成及其整体布局形式,讨论了原型特征的组成,分类规则及其表示方法,给出了布局模板支持下的基于特生方案设计建模过程,研究成果为计算机辅助方案设计系统的实现提供了初步的理论框架。     

基于水平集方法的产品异构模型融合研究*

复杂产品设计往往涉及多个CAD/CAE系统,不同系统在几何模型构建、表达和存储等方面存在异构性,导致系统间数据和信息难以融合集成,降低了复杂产品的设计与开发效率。为了实现异构CAD/CAE模型语义信息和几何特征的融合,提出基于水平集方法的产品异构模型融合方法。构建了基于模型距离场的体素化模型,给出了体素化模型的可视表达方法,建立了距离场交、差和并集操作函数与产品造型特征复制、提取和识别的映射关系,建立了构造速度场操作函数和形位误差信息、高级语义信息和局部特征信息融合的映射关系,实现了产品异构模型的信息融合。通过复杂汽轮机叶片模型形位误差和高级语义信息融合试验,证明了方法在异构CAD/CAE系统信息集成方面的有效性和实用性。     

MODELING METHOD FOR PRODUCT STRUCTURE MAPPING BASED ON REVERSE SOLVING OF LOCUS AND MOTION

Aiming at the problem of structure design in reverse-design of mechanism, a structure mapping method based on reverse solving of locus and motion (RSLM) is presented. The mechanism scheme meeting the requirements of geometric and structural features is obtained through RSLM. The element instance subsets related to component are established based on the element type mapping, pair structure type mapping and design knowledge mapping between components and elements layer by layer. The assembly position mapping of elements is established based on the topological structure information of mechanism scheme, and the product modeling of structure mapping is realized. The algorithm program and prototype system of product structure mapping based on RSLM are developed. Application samples show that the method implements the integration of scheme design, assembly design and structure design, and modeling for product structure mapping based on RSLM. The feasibility of assembly is analyzed in scheme design that contributes to reducing the design error, and raising the design efficiency and quality.     

Extraction of machining features for CAD/CAM integration

Feature-based CAD/CAM integration is a technology used to realise automatic transmission and conversion of component information among CAD, CAPP and CAM applications. A feature is the medium of information transmission in the integration. Since a process planning downstream application has a different viewpoint from the component designer, feature conversion or feature extraction methodology is used to create a machining feature model based on the design feature model. One of the major difficulties in generating machining features is the preservation of feature integrity because of feature interactivity. The most current research, therefore, focuses on the planar-type form feature conversion. This paper discusses the problem of feature interactivity and proposes a feature-based approach to generating hole-series machining features from a design feature model. Hole-series features are important machining features for gearbox components used in machine tools. These kinds of features cannot be obtained directly from a design feature database. A constraint-based method is developed in this paper to define a hole-series feature model based on the geometric and topological information extracted from the design database. In addition, a STEP file is generated to interface the converted machining feature model with the downstream CAPP application. The implemented feature conversion system is verified by considering its application to some component examples and the developed prototype CAPP system. This revised version was published online in October 2004 with a correction to the issue number.     

基于布局模型的液压机大规模定制设计

为实现液压机产品的大规模定制快速响应设计,提出了一种基于布局模型的产品设计方法。通过构建液压机的产品功能需求模型、运动功能模型和模块结构模型之间的映射,将得到的布局结构实例化,采用有限元和变量化方法进行布局结构的分析和优化,从而得到最优布局模型。分析得到的所有布局模型将作为产品平台的一部分加以存储,以支持产品的大规模定制设计。论述了液压机产品布局模型的拓扑结构和约束信息表达方法。最后给出了基于布局的大规模定制产品的配置和变型设计过程,该过程显示,布局模型的研究与应用可明显提高液压机类机械产品的设计效率。另外,对产品布局模型在大规模定制产品平台开发过程中进行了分析,完善和补充了大规模定制产品平台体系。     

An approach to incremental feature model conversion

A new approach to converting a design feature model (DFM) to a machining feature model (MFM) step-by-step during a design process has been proposed. In the approach, the MFM is incrementally set up and updated through performing a local machining feature recognition on certain areas of a design part’s B-rep when its design features are updated. The areas to be recognized as machining features are determined through geometric reasoning according to the statuses of the DFM and the dynamically generated MFM of the part. To facilitate the above geometric reasoning, a dynamic link list (DLL) has been developed to record the changed topological elements during the design process and the relationships between the DFM and the MFM. Based on the automatic and effective conversion process from design models to machining feature models, the proposed approach can support the establishment of a concurrent product development environment to link product design and manufacturing processes seamlessly.     

Towards a tolerance representation model for generating tolerance specification schemes and corresponding tolerance zones

In this paper, a tolerance representation model for generating tolerance specification schemes and corresponding tolerance zones is proposed to meet the requirement of the representation of tolerance information semantics. This model is hierarchically organized and consists of five layers. They are component, geometric feature, variational geometric constraint, tolerance specification scheme, and tolerance zone layers. The mating relations between components in the component layer, the mating relations between geometric features in the geometric feature layer, the variational geometric constraints between geometric features in the variational geometric constraint layer, the tolerance specification schemes of component in the tolerance specification scheme layer, and the tolerance zones of tolerance specification schemes in the tolerance zone layer are formally defined by one or more adjacency matrices, respectively. Based on the model, a method for generating tolerance specification schemes for component and their resultant tolerance zones is designed. This method shows how to adopt a top-down strategy to carry out tolerance specification for an arbitrary assembly designed in a CAD system. The paper also provides a practical example to illustrate how the method works.     

Design and manufacturing interface modelling for manufacturing processes selection and knowledge synthesis in design

The research results presented in this paper are related to the specification of a method and models that tackle the problem of manufacturing processes selection and the integration, as soon as possible, of their constraints in the product modelling (i.e. information synthesis). This method is based on a skin and skeleton design/manufacturing interface model that ensures connection between design and manufacturing information. The use of these features is justified by their capacity to make a product representation which allows integration of both design and manufacture data and therefore assists the product breakdown definition (including the 3D forms) by least commitment. This method first analyses the product data issued from functional analysis and component selection (form, roughness, tolerance interval, etc.). Then, it deals with manufacturing information (manufacturing processes constraints). The approach is formalised with IDEF and UML models and has been consolidated with software developments based on C++ and open CASCADE technologies.     

基于三维几何特征的产品报价方法

针对当前主流报价系统对产品实例库的多样性和时效性要求高且报价响应效率低的问题,在研究自动特征识别技术和CAD二次开发方法的基础上提出了基于三维几何特征的产品报价方法。首先,对常用设计特征进行分类并建立设计特征标识号、设计特征和加工特征间的映像关系,利用特征标识号和设计特征间的一一映像关系完成设计特征的识别,结合设计特征与加工特征的映像关系实现加工特征的识别;其次,通过零件的材料费用和特征加工费用进行零件的报价研究,综合产品、部件及零件的报价层次关系建立产品报价模型;再次,为快速响应用户个性化需求,建立了从用户需求到产品配置再到快速响应报价的服务模型;最后,开发了基于Creo的三维几何特征的报价系统,并将该报价系统应用于某企业大功率逆变器报价中,提高了产品报价效率,验证了基于三维几何特征的产品报价方法的可行性。