盒型CAD系统的设计和实现

为提高折叠纸盒设计的效率和准确度，设计并实现了一个盒型CAD系统．提出了一个盒型数据描述格式PKS．运用参数化设计和零件装配技术生成二维盒型结构图；同时根据二维数据自动生成包装盒的三维模型．     

用Inventor进行三维设计

机械产品研制过程中的问题往往集中在部件装配、整机装配时发生,如在产品设计过程中采用三维CAD系统进行设计,则在零件的三维模型基础上,可以在计算机中完成零部件或产品的预装配及运动仿真,这样可以及时发现问题并且修改,同时针对设计好的零部件和装配体,计算机可以自动生成各种工程视图,大大提高了设计效率。Inventor是Autodesk公司最新推出的第三代机械设计软件,具有三维建模、装配、可视化和制图等方面功能。下面以弹性支承为例说明在Inventor中实现机械产品三维设计的过程。该弹性支承由底座、调整螺钉、弹簧、支承柱、顶丝…     

基于组件的典型零部件快速设计系统的开发

文章提出了一种基于组件技术的典型零部件快速设计系统的开发技术,通过开发基于组件的典型零部件设计校核模块,建立基于XML技术的典型零部件的模型库及其管理模块,同时为适应工程图的要求,开发了国标符号程序库,达到了跨多种CAD平台的软件及设计资源复用的需要。并以Pro/E平台为例,通过API接口组件的开发,实现了该平台下的典型零部件的设计计算、造型、生成符合国标的工程图,极大地提高了设计效率。     

虚拟装配程序可视化生成平台的设计与实现

通过分析快速生成虚拟装配程序的需求以及比较现阶段两种虚拟装配程序生成方法,在基于模板的代码自动生成技术的基础上,提出虚拟装配程序可视化生成平台VRMLPlatForm的设计思想,进行该平台用户界面的制作和各功能点的实现。在此平台下,列举矩形联结器移动、虚拟装配动作的可视化和程序的快速生成。将该平台应用在柴油机泵组虚拟装配培训系统的开发中,其结果验证了该平台在虚拟装配仿真动画制作过程中的巨大优势。     

耐火砖模具CAD系统智能化设计方法的研究

利用面向对象的机制将常见的耐火砖原型按其拓扑结构关系建立基类，以耐火砖的三维模型及其与模具的装配关系为基础，将三维造型、参数化设计、数据库等技术有机结合．在用户仅输入成品耐火砖各项参数的情况下，自动生成边、堵、底、盖等6个模板的三维实体，进而生成其零件图，实现了耐火砖模具设计的智能化．     

三维实体装配分析软件设计及其工程应用

目前，CAD技术正由单一分离的零件部件设计向着系统分析、综合实用化方向发展。通过三维系统装配技术，对实体建模构造的零部件系统进行结构方案布置、装配连接、完整模拟产品的结构（包括几何、物理、装配）、准确反映设计人员的设计思想，具有重要的工程应用意义。在高级造型扩展软件AdvancedModelingExtension（AME）RZ．l平台上，我们结合履带车辆行动部分实际应用，研究了行走系统零部件的参数化特征造型和总体系统与零部件间的装配连接关系，并给出了行走系统零部件三维实体装配完成后的结果。探讨了零部件间干涉检查和相对间隙…     

基于国产数据库的飞机典型结构件库设计与实现

针对飞机零部件结构的相似性对飞机典型结构件进行归纳总结,构建异构CAD平台上的飞机典型结构件库系统是实现数字化设计制造模式下产品快速研制的有效途径．采用面向对象思想对典型结构件进行分析,并基于参数化造型方法和模型一视图一控制设计模式,实现典型结构件库的设计与开发;阐述了基于OpenBASE的数据库存储模式设计和基于CAA FOR CATIA V5R13的系统实现技术．     

基于模板的港口码头三维结构CAD/CAE 集成技术

针对港口码头结构CAD 几何模型生成CAE 单元模型,工程荷载CAD 模 型创建CAE 荷载模型,和CAE 分析结果与CAD 模型的关联关系等问题,利用模板的模型 独立性、规则性和可执行性等特性,研究了基于模板的港口码头三维结构CAD/CAE 集成技 术,定义了截面草图、三维实体和构件等多种CAD 建模模板,定义了机械草图和荷载等多 种荷载建模模板,定义了CAE 分析规则,实现了CAD 几何模型自动生成CAE 单元模型的 功能,定义了荷载转换规则,实现了工程荷载CAD 模型自动创建CAE 荷载模型的功能, 定义了整体模型模板,建立CAE 分析结果与CAD 模型的多对一关系,以此实现了港口码 头三维结构CAD/CAE 集成系统,大大提高了港口码头的设计效率,降低了设计人员的设计 难度,减少了设计错误。     

工业建筑预埋件三维快速装配设计方法

当前工业建筑结构预埋件设计主要采用二维CAD 软件,效率较低且容易 出错。为此提出基于广义参数化模板的三维预埋件快速装配设计方法。该方法建立包含三维 参数化形状结构、安装定位方式和二维投影简图等各种信息的预埋件广义参数化模板;通过 构建预埋件参数化模板库,采用基于历史的装配设计技术,实现预埋件的快速安装设计。该 文方法已经集成到商品化工业建筑结构三维CAD 软件InteRDS 中,并在实际工程设计中得 到应用。     

圆锥齿轮实体参数化逆向造型设计

提出实体参数化逆向造型设计的方法，介绍应用该方法开发圆锥齿轮三维实体参数化造型设计系统的过程。采用小型CAD软件的基本造型功能对圆锥齿轮三维基体作造型设计，再利用其宏记录自动生成程序的功能将宏文件和齿形生成程序结合，在Visual Basic环境下实现圆锥齿轮基体与齿形三维实体参数化逆向造型设计。旨在提供一种对CAD软件二次开发的新方法，使设计者掌握运用该方法对复杂三维实体进行参数化设计，从而提高开发小型CAD软件的能力。     

椭圆类齿轮参数化设计与运动仿真系统的开发

非圆齿轮因其节曲线为非圆形,计算复杂,设计困难,目前的三维设计软件都无法直接进行实体建模。根据非圆齿轮的设计理论,利用Visual Basic 6.0良好的界面设计功能和计算能力对SolidWorks进行二次开发,设计出椭圆类齿轮参数化设计与运动仿真系统,实现了椭圆类齿轮的三维参数化建模与运动仿真。论述了系统的开发过程,运行实例表明系统界面友好,设计正确。解决了椭圆类齿轮设计中的复杂计算和三维实体造型难的问题,可提高设计精度、缩短产品开发周期,保证产品质量。     

基于SolidWorks实现系列零件的快速设计

为了实现制造业系列化零件的快速设计,结合当今主流的三维设计软件SolidWorks平台,详细阐述了综合运用系列化列表、尺寸驱动方程,共享数值链接及API编程方法,快速、准确地建立系列件的母模型,避免了为每个零件都建立各自的模型,实现了系列件生成的自动化,随用随生成,大大降低了零件库的存储空间.实践结果表明,该设计能有效提高了产品开发效率,并且降低了对开发人员的技术要求.     

Template-based AADL automatic code generation

Embedded real-time systems employ a variety of operating system platforms. Consequently, for automatic code generation, considerable redevelopment is needed when the platform changes. This results in major challenges with respect to the automatic code generation process of the architecture analysis and design language (AADL). In this paper, we propose a method of template-based automatic code generation to address this issue. Templates are used as carriers of automatic code generation rules from AADL to the object platform. These templates can be easily modified for different platforms. Automatic code generation for different platforms can be accomplished by formulating the corresponding generation rules and transformation templates. We design a set of code generation templates from AADL to the object platform and develop an automatic code generation tool. Finally, we take a typical data processing unit (DPU) system as a case study to test the tool. It is demonstrated that the autogenerated codes can be compiled and executed successfully on the object platform.     

BIM技术在农村住宅结构CAD软件后处理系统中的应用

基于BIM技术研制适用于各种农村住宅结构形式的CAD软件后处理系统.根据面向对象的编程原理,抽象出描述实际结构零件几何信息、结构特征和设计条件的智能对象.采用三维实体建模直观、准确和完整地展现结构的复杂空间位置关系和细部构造;在实体模型的基础上选取特定的实体,提取其中的几何信息,经过投影、消影和自动标注绘制完成施工图和加工图.该软件系统能提取三维实体模型中的构件和零件的加工信息,并按照CNC设备的数据格式要求整理输出为二进制数据或Excel等.     

基于广义模块库的自动武器网络化快速设计

在自动武器三维模块化参数化程序的基础上,从支持网络化快速设计的角度出发,通过对自动武器共享协同设计的特殊需求进行分析,建立网络协同设计模块库管理系统模型,介绍自动武器快速设计系统的三维模型共享协同设计流程,给出保证数据传递完整性及快速性的模型多线程传输及基于层次结构的装配文件压缩处理等关键技术的实现方法。     

手机短信3D动画中光照规划的自动生成

手机短信3D动画自动生成系统是根据发送方短信的内容,经过信息抽取、语义分析等一系列步骤,最终生成一段与短信内容匹配的三维动画并发送给接收方.动画中光照不仅能照明整个场景,还能起到烘托主题、表现氛围等作用.本文重点研究面向手机短信3D动画自动生成系统中光照的自动生成,主要从定性规划和定量计算两方面着手.定性规划的主要任务是通过本体库刻画与光照相关的主题、模板,利用规则库将主题、模板、场景、光照属性等以规则的方式关联起来.定量计算的主要工作是结合具体场景,将定性规划的信息转化为具体数据,然后调用Maya API,将定性规划的结果在Maya场景中实现.     

Target recognition via 3D object reconstruction from image sequence and contour matching

This paper proposes an automatic target recognition (ATR) system based on the three-dimensional (3D) reconstruction of the target from an image sequence. The main contribution of this work is twofold: (1) we present a modified voxel coloring reconstruction algorithm and (2) we employ the 3D reconstructed target model to generate the front and side target templates at zero depression angle to be used in the target recognition process. Target recognition is performed by matching the generated templates to a library using a subpixel contour matching algorithm. Experimental results on simulated scenes show the accuracy of the approach presented in this paper.     

Computational Design and Optimization of Non-Circular Gears

We study a general form of gears known as non-circular gears that can transfer periodic motion with variable speed through their irregular shapes and eccentric rotation centers. To design functional non-circular gears is nontrivial, since the gear pair must have compatible shape to keep in contact during motion, so the driver gear can push the follower to rotate via a bounded torque that the motor can exert. To address the challenge, we model the geometry, kinematics, and dynamics of non-circular gears, formulate the design problem as a shape optimization, and identify necessary independent variables in the optimization search. Taking a pair of 2D shapes as inputs, our method optimizes them into gears by locating the rotation center on each shape, minimally modifying each shape to form the gear's boundary, and constructing appropriate teeth for gear meshing. Our optimized gears not only resemble the inputs but can also drive the motion with relatively small torque. We demonstrate our method's usability by generating a rich variety of non-circular gears from various inputs and 3D printing several of them.     

Deformation modeling for robust 3D face matching

Face recognition based on 3D surface matching is promising for overcoming some of the limitations of current 2D image-based face recognition systems. The 3D shape is generally invariant to the pose and lighting changes, but not invariant to the non-rigid facial movement, such as expressions. Collecting and storing multiple templates to account for various expressions for each subject in a large database is not practical. We propose a facial surface modeling and matching scheme to match 2.5D facial scans in the presence of both non-rigid deformations and pose changes (multiview) to a 3D face template. A hierarchical geodesic-based resampling approach is applied to extract landmarks for modeling facial surface deformations. We are able to synthesize the deformation learned from a small group of subjects (control group) onto a 3D neutral model (not in the control group), resulting in a deformed template. A user-specific (3D) deformable model is built by combining the templates with synthesized deformations. The matching distance is computed by fitting this generative deformable model to a test scan. A fully automatic and prototypic 3D face matching system has been developed. Experimental results demonstrate that the proposed deformation modeling scheme increases the 3D face matching accuracy.     

The design and realization of CoViD: a system for collaborative virtual 3D design

Many important decisions in the design process are made during fairly early on, after designers have presented initial concepts. In many domains, these concepts are already realized as 3D digital models. Then, in a meeting, the stakeholders for the project get together and evaluate these potential solutions. Frequently, the participants in this meeting want to interactively modify the proposed 3D designs to explore the design space better. Today’s systems and tools do not support this, as computer systems typically support only a single user and computer-aided design tools require significant training. This paper presents the design of a new system to facilitate a collaborative 3D design process. First, we discuss a set of guidelines which have been introduced by others and that are relevant to collaborative 3D design systems. Then, we introduce the new system, which consists of two main parts. The first part is an easy-to-use conceptual 3D design tool that can be used productively even by naive users. The tool provides novel interaction techniques that support important properties of conceptual design. The user interface is non-obtrusive, easy-to-learn, and supports rapid creation and modification of 3D models. The second part is a novel infrastructure for collaborative work, which offers an interactive table and several large interactive displays in a semi-immersive setup. It is designed to support multiple users working together. This infrastructure also includes novel pointing devices that work both as a stylus and a remote pointing device. The combination of the (modified) design tool with the collaborative infrastructure forms a new platform for collaborative virtual 3D design. Then, we present an evaluation of the system against the guidelines for collaborative 3D design. Finally, we present results of a preliminary user study, which asked naive users to collaborate in a 3D design task on the new system.