基于并行工程的汽车部件CAD系统

主要研究了并行设计在汽车部件ＣＡＤ系统开发方面的应用。将所要设计的汽车部件在计算机上模拟为一个三维的完全数字化的实体模型,使设计、分析计算、装车检验、工业造型作为一个并行的工程来研究;利用人机工程、动态仿真、虚拟装配等关键技术,克服了传统的设计方法设计周期长、成本高、产品质量低等方面的弊端,使汽车部件的设计符合现代化设计的潮流。     

基于特征的CAD参数化建模技术及其应用

在对现有特征技术进行总结的基础上提出了特征的定义。结合粗纱机牵伸部件给出了面向设计的特征分类并建立了基于特征的参数化建模框架。在Pro／E平台上利用其二次开发工具Pro／Program给出了某厂粗纱机牵伸部件的建模实例。     

平面连杆机构的计算机辅助设计

所介绍的自行开发的平面连杆机构计算机辅助设计系统，能对常用的平面连杆机构进行运动分析及综合。阐述了该系统的结构，系统设计的原则、设计目标以及有关的建模与求解方法，最后给出一个应用实例。     

锥齿轮——三级行星齿轮减速器系列产品全参数化CAD系统

介绍锥齿轮－三级行星齿轮减速器产品系列化，全参数化ＣＡＤ技术，以及全参数化设计，有限元分析，绘图三部分软件功能。     

产品概念设计自动综合求解与系统实现

运用键合图方法定义了基本元件，并提取其输入输出特征与能量传递和转换函数。研究了单输入单输出机械产品的概念设计自动求解。提出了目标驱动的逐段综合求解策略和基于模糊距离的方案评价方法，开发了相应的概念设计原型系统。结合面向对象和规则方法来表达设计知识，其中面向对象方法用来封装元件，形成元件类，规则则用来指导搜索过程。通过自动门驱动装置的设计实例，说明该方法适用于定常和非定常的设计要求。     

三维水工配筋CAD系统的集成方案

提出了一种全新的水工结构配筋设计系统集成方案。与传统方案不同，系统直接从水工结构三维实体模型入手，集建模、分析、配筋、出图为一体，通过对水工模型的有限元分析，结合水工配筋专家知识来确定配筋方案与配筋参数，能自动完成三维布筋和二维出图，并可实现相关数据的自动统计，从而极大地提高了水工配筋效率。     

MECSYN-IMP-ANIMEC: Foundation for a new computer-aided spatial mechanism design system

The basis for a new computer-aided mechanism design system is described. It includes the programs MECSYN for synthesis. IMP for analysis, and a new program, ANIMEC, for automatic geometric modelling, assembly and animation of planar mechanisms. Key features of the system are effective graphical input, a common synthesis-analysis database and realistic automatic modelling and animation output for rapid evaluation of results. An example session showing synthesis, analysis, automatic modelling and animation is presented.     

Synthesis of RSSR-SRR spatial motion generator mechanism with prescribed crank rotations for three and four finite positions

The mechanism considered here is an RSSR-SRR spatial mechanism for motion generation with prescribed crank rotations. It consists of an R-R-R (R = revolute, S = spheric joint) fixed frame, two grounded R-S links, one grounded RRS dyad and a ternary S-S-S coupler. Motion of the coupler is to be prescribed for three and four finitely separated positions and to be correlated to the prescribed input rotations of the crank, the grounded R-R link of the RRS dyad. The synthesis equations obtained by using vector mathematics are linear in the unknowns up to three prescribed positions of the body in spatial motion. For four precision positions, the design procedure involves solving two cubic algebraic equations simultaneously for two unknowns for the R-S dyad synthesis, and solving one fourth-degree algebraic equation in one unknown for synthesis of the RRS group. The design procedure is described in detail and numerical examples are presented for illustration.     

Towards an environment for the integration of analysis and design

In recent years, the major emphasis of CIM research and development activity has been in the area of automated manufacturing, where technical and economic feasibility is critical for a viable CIM environment. However, to achieve a truly integrated manufacturing environment, it is necessary to integrate design activities into the structure. Although computers have been used for many years in the design process the present situation is not satisfactory, particularly for small and medium-sized industries. In most cases, computer-aided drafting tools are provided, but they are seldom integrated into the design process and the dependent analysis tools are still only available via separate and frequently unrelated analysis codes. Possible ways of improving the situation are discussed: these include improving the robustness of analysis codes by error estimation, adaptive meshing and postprocessing features, and providing an effective integrated environment, with drafting and design tools.     

3D-MCM高集成微波模块的热设计研究和应用

文中针对3D-MCM高集成模块的散热问题,研究了3D-MCM组件在高能量密度、高集成度下的热设计,并以3D-MCM信号处理组件为例,根据信号处理组件电性能设计和封装布局设计要求,建立了参数化的有限元仿真模型。经过布局迭代、散热方式优化和组件材料优化,组件的等效热导率高达 76 W/(m·K),封装基板局部的热导率可达183 W/(m·K)。基于氮化铝基板和纳米银等高导热材料,实现了高集成信号处理组件的高效散热设计。     

Identification of the Basic Parameters of an Aircraft Wing

A method of identifying the basic parameters of airplane components is proposed on the basis of correlation and factorial analysis, with the subsequent derivation of polynomials by the least-squares method and by Brandon’s method. A multiparametric approach to design analysis and synthesis is formulated on the basis of a formalized process. This approach permits clear decisions for individual aircraft components at the preliminary design stage, as demonstrated here for the example of a wing.     

An Automated CAD System for Progressive Working of Irregular Shaped Metal Products and Lead Frame for Semiconductors

This paper describes the development of computer-aided design of irregular-shaped sheet metal products and 32LD PLCC lead frames and semiconductors, requiring very precise piercing operations for progressive working. The approach to the CAD system is based on knowledge-based rules. Knowledge for the CAD system is formulated from plasticity theories, experimental results, and the empirical knowledge of field experts. This system has been written in AutoLISP using AutoCAD on a personal computer and the I-DEAS drafting programming language on the I-DEAS master series drafting with an HP 9000/715(64) workstation. Transference of data between Auto-CAD and I-DEAS master series drafting is accomplished using DXF and IGES methods. This system is composed of five main modules, which are input and shape treatment, production feasibility check, strip-layout, data-conversion, and die-layout modules. Based on knowledge-based rules, the system is designed by considering several factors, such as V-notches, dimple, pad chamfer, spank, cavity punch, camber, coined area, cross bow, material and thickness of product, complexities of blank geometry and punch profile, and availability of presses. As forming processes and the die design system using 2D geometry recognition are integrated with the technology of process planning, die design, and CAE analysis, the standardisation of die parts for lead frames requiring a high precision piercing process is possible. The die-layout drawing generated by the die-layout module is displayed in graphic form. Results obtained for each module provide help to the designer and the manufacturer of lead frames for semiconductors.     

UG在天线结构设计中的应用

本文简单介绍了在 Unigraphics环境下 ,利用 UG强大的实体建模、装配建模及工程制图等模块 ,设计天线结构并进行效果仿真及结构分析 ,最后完成工程制图的实践。文中给出一个具体的天线及其相关波导器件的 CAD设计实例。     

结合连续法与数值图谱法的平面四杆刚体导引机构尺度综合

根据已有的连杆机构尺度综合方法，首先用复数法得到四杆机构的刚体导引综合方程组，再由连续法得到满足设计要求的精确解。然后经过快速傅立叶变换得到与方程精确解对应的四杆机构连杆转角函数的谐波成分，利用这些谐波成分参数，通过模糊识别的方法，从已建立的四杆机构连杆转角函数谐波特征参数的“数值图谱”中找到更多满足要求的机构。最后给出了算例对其进行验证。     

微机集成化智能CAD系统Iute CAD

介绍了一个集成化智能化ＣＡＤ系统ＩｕｔｅＣＡＤ。该系统在微机上开发而成，具有较强的设计、分析、绘图功能。介绍了ＩｕｔｅＣＡＤ系统的体系结构和实现技术。     

Geometrische synthese eines viergliedrigen räumlichen doppelgetriebes vom typ RSCRGeometrical synthesis of a four-link spatial mechanism of the type RSCR

At the present time a large portion of the literature associated with mechanism synthesis is devoted to methods based on numerical algorithms. It is interesting to note, however, that geometric synthesis procedures often allow a deeper insight into the significance of kinematic motions than is provided through numerical procedures. for this reason the authors have developed synthesis methods based on projective geometry. The method is applied to the design of the RSCR mechanism for three finitely spaced positions. The method is illustrated by means of an example problem.     

Integrated design and manufacturing ultilising a personal computer: A woodworking-industry application

An integrated design and automated manufacturing system for making cabinet doors has been developed and implemented. A standard CAD package is used for designing the components and a CAM system, consisting of a modified industrial woodshaper and additional motion-control hardware, produces the components. A software environment has been developed to integrate both design and manufacturing functions. The system has been shown to reduce the time for designing and manufacturing a single door by a factor of four.     

臂架型斗轮堆取料机俯仰液压系统分析

总结了斗轮堆取料机液压式俯仰机构中液压系统的设计要求,并以浙江北仑发电厂二期输煤系统中的斗轮堆取料机俯仰液压系统为例,对俯仰液压系统中各项设计要求的实现方法进行了详尽分析和说明,可为采用类似结构的堆取料机俯仰液压系统的设计、改造和故障分析等提供帮助。     

Analytical modeling and FEM Simulations of single-stage microleverage mechanism

Microleverage mechanisms have potentially wide applications in micro-electro-mechanical systems (MEMS) for transferring an input force/displacement to an output to achieve mechanical or geometrical advantages. Constrained by micro-fabrication technology, a microleverage mechanism is made of planar flexures, achieving mechanical transformation through elastic deformation. This kind of mechanism is referred to as a compliant mechanism. In this paper, the analysis and optimization of a single-stage microleverage mechanism is presented with a double-ended tuning fork as the output system in a resonant accelerometer to address the design issues. A very good agreement is obtained between the results of analytical modeling and those of FEM simulation with a SUGAR software package. Although the SUGAR data are more accurate, the analytical equations give clearer insights as to how to design a microleverage mechanism. While high axial spring constants and low rotational spring constants are desirable, the axial and rotational spring constants at pivot need to match those at the output system to achieve the maximum force amplification factor. This compliance-match concept is very important for the design of both single-stage and multiple-stage leverage mechanisms.     

某机修厂供电系统设计

介绍了供电系统的组成和供电系统主要元件的选择依据,并以某机修厂35kV供电系统的设计为例介绍了供电系统的设计。