面向轮胎3D花纹的语义建模方法

针对以几何特征为主导的建模方式会造成轮胎3D花纹模型创建操作繁琐、设计信息表达分散且不完备的问题,提出了以语义为主导的3D建模方法。该方法是在花纹设计的应用理论及实用技术探讨和研究的基础上,将理论设计中的花纹沟、装饰品及交汇特征的结构抽象分解得到轮胎花纹语义单元,从而构建花纹语义模型库和结构设计知识库。在此基础上引入轮胎节距信息,实现了轮胎花纹从概念设计到装配设计的层次化、系统化、形式化表达。最后,以CATIA/CAA为开发平台引入基于特征的建模技术,开发出语义级轮胎3D花纹设计系统。实例分析结果表明,该系统适用于多种类型的轮胎花纹建模,提高了CAD技术对设计信息表述的支持能力,增强了产品建模的自动化水平,有效地减少了设计人员的重复性工作,缩短了研发周期。     

基于适应性装配特征的自动装配技术研究

装配设计是现代CAD技术中的一个重要组成部分,但其中对零部件自动装配的研究还相对薄弱。笔者在研究参数化设计和装配建模的基础上,提出了基于适应性装配特征的零部件自动装配方法,根据适应性装配特征来确定零部件间装配关系和装配对象的主参数,以便适应调整装配对象姿态、完成自动装配、提高装配设计的速度和效率。根据以上研究开发的基于CATIA平台的导管焊接夹具自动装配模块,验证了该方法的有效性和实用性。     

基于Solidworks的膨化机CAD系统的研究

膨化机CAD系统是基于机械自动化设计软件Solidworks开发的。整个系统使用VisualC 语言开发,以动态链接库的形式嵌入Solidworks系统。论文详细介绍了系统的各个功能模块和实现方法,即数据输入、设计计算、参数化三维零件造型、装配体三维造型和工程图输出。零件自动三维造型的实现采用了以尺寸驱动为主、程序驱动为辅的编程思想。系统完全被封装在Solidworks的一个菜单项下,通过简单的人机交互,输入功率、转速等设计参数后,就能自动完成整台膨化机的结构设计,然后根据用户选择输出零件或者装配体的三维造型图和工程图。     

Efficient method of assembly sequence planning based on GAAA and optimizing by assembly path feedback for complex product

In the process of complex product assembly, assembly resources (fixtures, tools, operations, and so on) must enter assembly environment with parts together to rapidly finish product assembly. Assembly planning must take assembly resources into account fully. But, designer cannot plan every assembly procedure because of the lack of assembly resources during assembly design. Then, it will cause assembly failures and redesign for assembly easily. This paper investigates an efficient method of assembly sequence planning based on genetic algorithm and ants algorithm (GAAA) and optimizing by assembly path feedback to assembly process planning including assembly resources for complex products. Firstly, a new GAAA is investigated to rapidly plan assembly sequence in order to solve the nondeterministic polynomial-bounded problem in high searching and solving efficiency. Secondly, on the basis of the assembly sequence, a B-Rep filling algorithm which can form a swept volume between the part and its kinetic orientation is developed to plan assembly path interactively. Thirdly, the performance of the assembly path according to the assembly sequence is analyzed and sent back to avoid the most of assembly collisions and interventions during product assembly design. Lastly, we develop a simulating system to simulate assembly sequence and path based on component application architecture for CATIA V5. The simulating result proved that the proposed method of assembly sequence planning based on GAAA and optimizing by assembly path feedback for complex products is efficient. Assembly optimal design including assembly resources can work well.     

系统中搬运机械手的本体结构设计

根据教学培训系统总体设计方案及机械手设计要求,经设计分析后利用Pro/E软件逐步进行机械手零件结构三维参数建模并完成总体装配。装配虚拟样机经干涉检查、运动仿真等初步分析后达到预期结构设计要求,各设计零件经加工后装配得到实物并运用于系统中。     

开放式装配设计模型的研究和实现

分析了常用装配设计模型的特点和要求 ,运用组件思想及其技术提出了基于广义环图树的开放式装配设计模型。此模型结构简单 ,扩展能力强 ,特别适合于在三维设计系统上扩充开发专用功能组件。开放式装配设计系统模型已在 Inte Solid 1.0上得到应用 ,将在Inte Solid2 .0上得到完善和进一步应用。     

面向概念设计的产品装配结构定性模型

通过对实体零件在装配层次上的抽象以及基于抽象零件的装配建模,建立了产品符号装配模型。针对概念产品装配结构的定性特性,通过对符号装配模型中零部件之间空间位置关系的定性描述,建立了面向概念设计的产品装配结构定性模型。讨论了装配副、符号装配关系、定性几何约束和定性几何约束图,并结合实例介绍了概念产品装配结构定性模型的建立过程。     

An effective integration approach toward assembly sequence planning and evaluation

An integration strategy for assembly sequence planning and sequence scheme evaluation is proposed. This strategy can be used to plan a reasonable assembly sequence, to optimize a sequence scheme, and to predict whether a collision will occur between the assembly tool and assembled components by considering factors like target components and assembly resources. A hybrid method is presented for assembly sequence modeling that combines human-computer interactive operations to manually build a hierarchical assembly sequence main model and a hybrid graph method to automatically generate sub-assembly sequence schemes of the main model. An optimization algorithm based on time-cost is introduced to handle a best candidate components selection. This relieves the problem of limited capability found when handling large size assembly models with traditional methods. The essential issues involved in system implementation are discussed as well; these include a representation method for the assembly consequence model, an optimization model of assembly sequence planning, and an object-oriented system architecture model employed with multi-agent technology for visually evaluating the assembling process. This system, KM computer-aided assembly process planning, KMCAAPP, has been developed on the basis of our previous work, KMCAD3; KMCAAPP uses the presented approach. KMCAAPP can be integrated with CAD model from KMCAD3D. A case study shows that the presented approach can use large CAD assembly models and delivers a feasible and effective way to integrate the assembly sequence planning process with scheme evaluation by visually evaluating the assembling process. This allows the identification of design errors in a timely manner and mitigates economic loss.     

Research of design and analysis integrated information modeling framework for multibody mechanical system: with its application in the LHD design

Many complex mechanical products can be considered as multibody systems; 3D computer-aided design (CAD), multibody dynamics, finite element-based strength and fatigue analyses, optimization, and other CAE tools, are often used to develop this kind of product. But design is difficult and challenging because of information inconsistence among different engineering domains, and isolated information model islands exist. Lots of research are attracted to design and analysis information integration, but attentions are mainly focused on integration of CAD–finite element analysis (FEA), supporting the bottom-up design principle, while multibody dynamics analysis for analyzing global performance of a mechanical system is rarely considered, which follows the top-down design principle. In this paper, a novel multilevel system representation modeling framework for supporting both bottom-up and top-down or mixed design methods is proposed. It can integrate the product design CAD models with multibody dynamics, finite element-based strength and fatigue analyses, realizing a CAD–dynamic–FEA–fatigue analysis integration. It can also support data exchange and transfer in multidomain analyses. The framework is illustrated with a case study of a load haul dump (LHD) design using currently available software tools. Furthermore, a design case study of the working unit of the LHD is given to highlight the applicability of the modeling framework for multibody mechanical systems. It has been demonstrated that the framework can describe information exchanging and integration among CAD, FEA-based strength and fatigue analyses, and multibody dynamics analysis during a multibody mechanical product design process.     

基于SolidWorks的电磁截止阀虚拟设计及动态仿真

为了更好的理解和认识电磁截止阀的内部结构和工作原理,以SolidWorks为平台,对电磁截止阀进行了产品零件的3D建模设计、虚拟装配、干涉检查和动态仿真,实现了零件设计和产品虚拟装配的互动,并且动态仿真过程可以录制成动画,有利于新产品的推广和应用。     

轮式装载机工作装置的仿真分析

利用三维造型软件UG建立轮式装载机工作装置的六连杆机构,通过多体动力学分析软件ADAMS实现虚拟仿真,通过仿真分析的结果对工作装置机构参数修改以及铰接点位置的重新设定,得出符合设计优化要求的机构参数和铰接点位置,以及油缸运动控制参数。为装载机工作装置的试制提供参考数据。     

基于设计意图的一体化智能装配建模与序列规划技术研究

装配建模和序列规划是数字化装配的重要组成部分,但设计意图（Design intent,DI）的丢失致使其相互割裂、智能化水平低。针对前期发现的"装配建模和序列规划一体化完成"的可能性,研究基于DI的一体化智能化装配建模和序列规划方法。分析前期基于交互特征偶（Interaction feature pair, IFP）的智能装配建模方法的局限及其原因,明确一体化智能装配建模和序列规划的总体方案;设计零件初步序列规划算法、复合IFP （Complex IFP, C-IFP）构造算法、零件预装配算法和C-IFP实例化算法,以及相关功能类,从而增强零件的"感知"能力,提升了装配建模和序列规划的智能化水平,并基于DI的一致性传递,实现了两个环节的相互促进、一体融合。通过简化的机械臂实例验证方法的可行性。该方法对于打破渐趋固化的串行数字化装配模式、丰富并发展数字化装配理论和技术体系具有积极意义。     

Top-down 方法在功放组件结构设计中的应用

兼顾企业现有的设计环境与传统设计流程,充分发挥Top-down三维设计软件的优势,使软件的操作由一般应用向高级应用过渡。文中以雷达发射系统中功放组件结构设计为例,探讨了电子机械领域小规模装配中采用Top-down方法建模的技巧。从功放组件三维装配文件入手,以总体结构及电讯布局为原始参照,通过复制几何、引用参照、参数传递等手段,建立起相关零件特征与顶层要素之间,以及不同零件特征之间的关联,实现了装配中相关零、部件的同步再生。文中还介绍了通过直接参照顶层特征或主体零件,实现在小规模装配中运用Top-down思想的方法。采用Top-down方法,显著加快了三维装配的建模速度,提高了设计准确性,同时也方便了产品的后期调整与更改借用,达到了快速设计的目的。     

装载机工作装置的遗传优化设计

反转六连杆机构是装载机工作装置的重要部分。建立了反转六连杆机构的数学模型，采用基于违约解转化法的遗传算法对其进行优化设计，并对装载机工作装置进行了性能分析评价。结果表明，采用优化设计后，铲掘位置时的反转六连杆机构传力比提高了7．22％，工作装置的性能得到进一步的完善和提高。     

装配/拆卸干涉矩阵的自动生成技术

讨论了基于ProEngineer三维设计模型的干涉矩阵自动生成方法。通过定义集成干涉矩阵来表达零件间装配/拆卸时的干涉关系,详细给出了产生干涉矩阵所需的零件/装配体信息提取和基于零部件运动扫掠体的干涉检查过程,采用干涉矩阵元素的二进制和十进制转换来降低计算复杂性,给出了干涉矩阵生成的算法流程并初步开发了原型系统。通过示例说明了系统的应用过程。     

港口机械行走装置参数化设计及三维虚拟仿真

研究了基于三维设计平台的港口机械中的行走装置参数化造型和仿真的自动化问题。以Solid Works三维平台为基础，建立行走装置的全部构件，并对其进行封装；通过构件约束方程式实现构件参数化造型；根据构件空间位置，按后台预置装配方法实现虚拟装配；并在面向对象环境下编制了行走装置的快速三维造型与仿真模块。     

自顶向下为基的CAD特征建模及其应用

文章提出了自顶向下设计的概念,给出了自顶向下的装配设计系统开发程序,提供了一个面向装配的设计环境,通过层次化的装配模型和参数化的建模技术,由产品的关键零件约束产生其它的零、部件,支持了产品从概念设计到详细设计,以Pro/ENGINEER软件为平台,减速器产品为对象进行了实际应用。     

基于自顶向下的三维CAD特征建模及其应用

现有三维CAD工具基于自底向上建模存在不足.本文提出了自顶向下设计的概念.给出了自顶向 下的装配设计系统开发程序,提供了一个面向装配的设计环境,通过层次化的装配模型和参数化的建模技术.由产品的关键零件约束产生其它的零、部件,支持了产品从概念设计到详细设计,以Pro/ENGINEER软件为平台,减速器产品为对象进行了实际应用.     

SolidWorks2001 Plus在装载机设计中的运用

主要介绍了三维CAD/CAM/CAE集成化机械设计软件SolidWorks2001 P1us的功能、特点，并运用此软件对装载机进行了三维建模、装配、渲染、运动仿真和二维视图转化的设计。     

虚拟装配技术在自动引导车转向系统中的应用

阐述了虚拟装配技术基本原理、过程和方法,提出了基于SolidWorks三维建模软件,以自动引导车转向系统为设计对象,进行三维建模和虚拟装配设计.先通过虚拟装配关系识别捕捉设计者的意图,然后利用装配约束条件确定零件的装配路径,并完成其装配,最后对自动引导车转向系统进行相应的干涉检验,并进行动画制作,进一步检测虚拟装配的可靠性.实践表明,利用虚拟装配技术可有效地缩短产品研发周期,节约成本和提高产品装配质量.