轻纺图案CAD/CAM研究

图案的设计和制作在许多行业,尤其是在轻纺业中占有非常重要的地位。到90年代后期,图案CAD/CAM技术己使得轻纺图案的设计与制作业产生了一次质的飞跃,大大促进了传统技术改造。但目前的轻纺图案CAD/CAM还不尽如人意,CAD和CAM两部分的发展还很不平衡。作者强调:轻纺图案CAD/CAM仍需融入新技术,增强新功能,以适应新的发展。     

一种新的半色调方法

印花行业中的半色调技术来源于印刷行业,众所周知,彩色印刷中的半色调技术主要采用调幅和调频两种方法,但是由于印花行业与印刷行业具体工艺的不同,两者的半色调技术存在许多不同的特点,而彩色印刷中的半色调方法并不能直接应用于印花行业,因此需要研究适合印花行业的半色调方法。针对印花行业的特点,本文提出了一种全新的挂网算法,该算法不仅能够满足印花行业特定工艺的需要,而且从根本上解决了印制云纹图案时容易产生龟纹     

CAD/CAM软件在虚拟制造中的应用及展望

本文概述了虚拟制造技术的概念,分析了在虚拟制造技术中CAD／CAM软件的应用特点。介绍了我国中小企业目前的状况和对CAD／CAM软件的需求。接着介绍了我国自主版权的CAD／CAM软件CAXA在烟台北极星模具厂生产过程中的应用。最后文章展望了CAD／CAM软件在未来制造业的发展。     

云马飞机制造厂CAD/CAM应用结硕果

CAD／CAM的诞生和成长与飞机制造工业有着不解之缘。企业开展CAD／CAM应用脱离不开世界CAD／CAM技术的发展。在我国，CAD／CAM的应用在七十年代首先在飞机行业开始，八十年代后期逐步发展到其它行业。云马飞机制造厂在原航空工业部的重点扶持下，从建厂开始就将CAD／CAM技术作为工厂技术进步的主攻方向和技术改造的主要内容。在CAD／CAM方面的的投资从建厂初期占全厂固定资产的1／10扩展到现在占1／5。七十年代初，我厂研制全天候飞机时大胆采用CAD／CAM一举成功，在我国飞机制造历史上开创了CAD／CAM的先河。九十年代…     

模具CAD／CAM软件的应用与开发现状

本文首先分析了模具行业采用模具CAD/CAM技术的原因。接着阐述了模具CAD／CAM应用情况和开发现状,最后指出了我国模具CAD／CAM软件应用与开发中存在的主要不足。     

钣金零件计算机辅助设计与制造

钣金加工CAD／CAM软件是机械CAD／CAM软件中的一个重要组成部分，它有其自身的特点与复杂性。工作站的CAD／CAM软件包中都包含有板金模块。在PC机上也出现了许多专门的饭金加工CAD／CAM软件包。在这众多的饭金加工CAD／CAM软件包中，专业性最强、功能最多、用户最多的当局美国的SMP－81板金加工CAD／CAM软件包。SMP－81软件包是美国Merry公司的产品。该公司主要从事饭全行业的CAD／CAM软件的研制、开发及销售，历时已15年之久。其产品SMP－81已遍布美国、德国、日本、新加坡、澳大利亚、韩国等国家，成为目前世界上最…     

纺织CAD系统中基于B样条的撇丝的算法研究

在实现面向绍兴轻纺行业的纺织CAD系统的过程中,为了更好更高效地模拟撇丝这种特色工艺的计算机实现,描述了用户指定的过控制点的B样条插值算法,然后提出了用这种插值算法来生成撇丝图案的详尽的原理和算法,再提出了一组撇丝的生成算法,最后通过效果图展示了算法的效果.这种算法已经成功地运用到了面向绍兴轻纺行业的CAD系统中.     

面向终端用户的CAD／CAM人机接口

本文阐述了面向终端用户的CAD／CAM人机接口设计思想，分析了CAD／CAM系统中人机交互的特点，并以此为基础构造了一个菜单生成器。按照这种新思想构造的CAD／CAM软件，既是一个CAD／CAM工具，同时又是一个CAD／CAM系统开发工具。     

数控玻璃雕刻CAD/CAM系统

本文在分析数控玻璃雕刻的特点及对CAD／CAM系统的要求的基础上，详细介绍了数控玻璃雕刻CAD／CAM系统构成、功能及关键技术。     

广州CAD运用成效显著

近几年,做为全国商业计算机应用试点城市的广州市在CAD/CAM应用方面一直是一枝独秀,目前全市已有近10家企业被国家科委评为全国CAD/CAM应用先进单位。记者近日采访了广州市计算机应用开发领导小组的黄仕雄先生,请他就广州CAD/CAM的推广应用工作做比较详细的介绍。 黄先生认为,广州CAD/CAM的推广应用之所以能取得今天的成果,关键一点是政府的支持,目前CAD/CAM主要应用在机械、建筑、造船、机电纺织等行业,这些行业中有相当一部分是老企业,资金困难,人才短缺。在这种情况下,广州市电子信息技术应用一直是把 CAD/CAM做为突破口。94年开始每年     

CATC — A Computer Aided Tolerance Control system

Computer utilization in manufacturing systems is increasing at a rapid rate. Developments thus far have been disjointed. Much work needs to be done in the area of integrating computer aided design and computer aided manufacturing (CAD/CAM). Tolerance control is an important component in the integration of CAD and CAM. Selection of design tolerances affects the build-ability of a product. The selection of manufacturing processes and sequence of processes affects process tolerance stacking. Unexamined process tolerance stacking leads to scrap and rework. A computer aided tolerance control (CATC) system is presented in this paper. This system is based on the tolerance chart technique. The CATC system is interactive and uses computer graphics for information display. The system can be used for computer aided process planning (CAPP) and for CAD/CAM integration.     

土木工程计算机绘图教学改革研究与实践

针对土木工程计算机绘图(CAD)教学中存在的缺点和教学课时不断压缩的压力, 从教学手段、教学方法和考核方式 3 方面提出了 CAD 教学改革方案。将 CAD 教学内容按照知 识点录制了 121 个 3~5 min 长度的微视频,通过超星学习通将微视频制作为《计算机绘图微课 程》,学生可利用碎片化时间在个人移动终端如手机、iPad (或平板)等上观看学习微视频。基于 微视频,采用任务驱动+翻转课堂方式开展教学,将学时缩短 1/4,注重学生创新学习能力培养。 取消卷面理论考试,将微视频完成度、习题完成情况,翻转课堂表现、三维创作、上机考试纳 入考核范围,加强学习过程管理和实际绘图能力考查。采用该方案的试点班与传统班对比发现, 不仅缩短了课时,还提高了期末上机考试平均成绩约 4 分,证明了该改革方案的可行性。     

Integrated Computer Aided Shoe-Making System

Shoemaking is one of the areas where CAD/CAM application is rapidly increasing.Thispaper introduces an integrated computer aided shoemaking system including human foot measuring,last(wooden model)measuring,last CAD/CAM and pattern CAD/CAM.The project was supported bythe 7th national economical 5 year plan.High technologies,suh as digital image processing,patternrcognition,advanced geometrical modeling and a series of sophisticated equipments and devices are ap-plied in this integrated system.Parts of the system have become commercial products.     

Computer aided design of form rolls for NC manufacture

Computer aided design (CAD) and computer aided manufacture (CAM) are two modern areas of computer application which have decisive influence in the manufacturing industries. The recognition of the potential of CAD/CAM is worldwide and many have taken advantage of the new technology. The design and manufacture of form rolls and the special tooling used in cold roll forming of thin walled metal sections are areas where the CAD/CAM approach can make a positive computer aided tool for creating form roll designs suitable for NC (numerical control) manufacturing. This work was undertaken by the Department of Production Technology and Production Management at the University of Aston in Birmingham in collaboration with a leading manufacturer of thin walled sections. Significant improvement of lead time and productivity in both design and manufacturing of form rolls have been accompanied.     

Neural networks for estimating the tool path length in concurrent engineering applications

This paper deals with the development of a neural computing system that can predict the cutting tool path length for milling an arbitrary pocket defined within the domain of a product design, in a computer numerically controlled (CNC) setting. Existing computer aided design and manufacturing systems (CAD/CAM) consume significant amounts of time in terms of data entry pertaining to the geometries and subsequent modifications to them. In the concurrent engineering environment, where even the designer needs information from the CAD/CAM systems, such time-consuming processes can be expensive. To alleviate this problem, a neural network system can be used to estimate machining time by predicting cost-dependent variables such as tool path length for the pocket milling operation. Pockets are characterized and classified into various groups. A randomized design is described so that the training samples that have been chosen represent the domain evenly. An appropriate network was built and trained with the sample pocket geometries. The analysis of the performance of the system in terms of tool path length prediction for new pocket geometries is presented.     

Surface flattening based on energy model

This paper presents a method for three-dimensional surface flattening, which can be efficiently used in three-dimensional computer aided garment design. First, a facet model is used to present a complex surface. Then, a spring-mass model based on energy function is used to flatten the 3D mesh surfaces into 2D patterns. The surface elastic deformation energy distribution is depicted by a color graph, which determines a surface cutting line. The method presented here can efficiently solve flattening problems for complex surfaces. The accuracy of a developed surface can easily be controlled locally. Thus, compared to earlier methods, this method provides more flexibility for solving CAD and CAM problems.     

基于四色和专色分色一体化工艺的数字印前系统的设计与实现

数字印前处理通常包括四色和专色分色两种技术。ＴＯＰ是一个集四色和专色分色两种技术为一体的ＣＡＤ／ＣＡＭ系统,能同时满足纸质印刷和织物印花的实际生产需要,以一体化工艺知识库为核心,设计了一种多层次系统结构;提出基于ＣＭＹＫ的四色分色和基于扫描线空间位置关系的两段法专色分色模型。两种分色技术的工艺统一表示为知识的形式,建成一个一体化工艺知识库。在一体化工艺的约束下对印制对象进行各种处理,以满足不同的需     

基于意图捕捉的适时智能辅助设计技术*

在设计师需要的时候提供适时、必要而不冗余的设计资源,是智能辅助设计软件系统最基本的特征。设计师意图的实时捕捉正是提供适时、必要资源的基础。通过研究设计过程中的人机交互行为,建立MultiAgent工作模型, 利用Agent从人机操作交互、上下文内容推理以及设计师的习惯符号化等方面实现设计师意图的捕捉,在此基础上构建一个顺应设计师设计思维发展和工作进程的智能辅助设计平台。     

计算机制版中的图像加网技术

将一幅彩色图像分成C，M，Y，K（青，品红，黄，黑）四个频道后，采用计算机制版中的图像加网技术生成带网胶片，通过控制网格的参数表达各频道颜色的明暗和层次。该技术准确，可靠，在彩色图像印染CAD系统中得非常好的效果。