基于Pro/TOOLKIT曲轴加工尺寸标注的智能化研究

本文阐述了轴类零件智能化技术标注尺寸与公差的基本原理及专家知识,针对发动机曲轴的结构和加工制造特点,对其产品的特征进行了分析研究,并以Pro/Engineer作为基础软件环境,应用Pro/TOOLKIT程序开发技术在VC 6.0环境下对Pro/Engineer进行了二次开发,对建立曲轴的参数化尺寸驱动的特征库和知识库进行了研究,从而实现曲轴加工尺寸标注的智能化.     

摩托车曲柄锻模高速加工

介绍了锻模的高速加工，论述了实施高速加工的支撑技术。     

CAM自带仿真模块与VERICUT仿真对比与综合运用

对CAM自带仿真模块与VERICUT仿真情况进行对比,以加工腔体零件前罩为例,从图形显示、干涉检查、程序的显示验证、尺寸检验以及程序优化等方面进行了对比,并分析了两类机械加工仿真模式的优劣,为不同需求的工程技术人员提供了仿真方法的借鉴和参考.为了更好的利用两类仿真软件,提出把两类仿真软件结合使用,并结合PDM工作环境,对CAM软件和第三方仿真软件的优势进行了整合,建立了全新生产准备模式下的信息模型,提出了新的新的生产准备方式.     

CAD/CAM系统中进度管理解决方案的研究及应用

提出了在ＣＡＤ／ＣＡＭ系统中的进度管理问题的解决方案,论述了进度管理系统的数据结构、系统构成和在设计时需注意的问题,并介绍了该方案在日本新泻铁工所横滨工厂热交换器ＣＡＤ／ＣＡＭ系统上的应用情况。     

A geometrical approach to computer-aided process planning for computer-controlled machine tools

This paper documents part of a research program which has been under way at the CIM Centre at Swinburne University of Technology since 1989. The purpose of the research program was to develop an open-architecture machine tool control system and then to see how that system could be used to change the distribution of traditional manufacturing design, planning and control functions. This paper examines one part of that research program and focuses on a methodology which could prove to be useful in the machine tool selection, cutter selection and cutter path generation phases of process planning for cutting operations on workpieces in computer-controlled machine tools.It is suggested that a configuration space transform be used for each cutter/machine tool combination to find the volume that the combination could remove from the uncut workpiece without removing any of the material that will form the final workpiece. A method of comparing these volumes from different combinations is then outlined. The output of this method is a reasonable sequence of machine tools and cutters. Path planning can then be carried out for each of the chosen combinations using a method similar to the one used to find the possible volume to be removed.Possible implementation techniques, and their limitations on existing computer hardware, are discussed and the most promising of these are identified, based upon some properties of configuration space transforms.     

A knowledge base model for complex forging die machining

Recent evolutions on forging process induce more complex shape on forging die. These evolutions, combined with High Speed Machining (HSM) process of forging die lead to important increase in time for machining preparation. In this context, an original approach for generating machining process based on machining knowledge is proposed in this paper. The core of this approach is to decompose a CAD model of complex forging die in geometrical features. Technological data and topological relations are aggregated to a geometrical feature in order to create machining features. Technological data, such as material, surface roughness and form tolerance are defined during forging process and dies design. These data are used to choose cutting tools and machining strategies. Topological relations define relative positions between the surfaces of the die CAD model. After machining features identification cutting tools and machining strategies currently used in HSM of forging die, are associated to them in order to generate machining sequences. A machining process model is proposed to formalize the links between information imbedded in the machining features and the parameters of cutting tools and machining strategies. At last machining sequences are grouped and ordered to generate the complete die machining process. In this paper the identification of geometrical features is detailed. Geometrical features identification is based on machining knowledge formalization which is translated in the generation of maps from STL models. A map based on the contact area between cutting tools and die shape gives basic geometrical features which are connected or not according to the continuity maps. The proposed approach is illustrated by an application on an industrial study case which was accomplished as part of collaboration.     

Standard process monitoring and traceability programming in collaborative CAD/CAM/CNC manufacturing scenarios

The paper focuses on collaborative STEP-based CAD/CAM/CNC supply chains to program and automate machining process data monitoring and traceability activities. A traceability interface (traceability nc_functions) is defined for the new CNC programming standard ISO STEP-NC. CAM systems will be able to program monitoring and data access activities by inserting traceability nc_function calls in CNC programs. On the shop floor, controllers will automatically interpret these nc_functions to access process data while machining and will relate data records with the corresponding machining operations in a STEP-NC part program. With both types of information—process data and standard machining program (STEP-NC part program)—spread and technologically heterogeneous engineering systems will have full knowledge about what has happened in production. Traceability data access automation will assure data reliability. The paper describes a traceability scenario where standards such as MTConnect and ISA-95 support, rather than interfere with, the STEP-NC traceability proposal.     

用二次插值实现近似弧长参数化

分段二次Ｈｅｒｍｉｔｅ插值用来保单调地反插值参数曲线的弧长函数．所作近似弧长参数化曲线在插值节点处,近似弧长是精确的,并且具有与精确弧长参数曲线同方向的单位切矢．在整个近似弧长参数区间,近似弧长的误差可达到０（△ｔ）＾２（△ｔ为节点步长）．数值实例得到了很好的结果．     

并行工程在汽车车身开发与制造上的应用

本文分析了常规车身ＣＡＤ／ＣＡＭ技术所存在的弊病,提出了采用并行工程的原理进行车身开发及车身工装设计与制造的方法。重点介绍了实施车身并行工程要解决的关键性技术,诸如建立集成化的产品数据模型、ＣＡＤ／ＣＡＰＰ／ＣＡＭ集成技术、建立多功能小组、计算机技术支持等。     

基于OpenGL的快速原形制造系统仿真

随着计算机技术的发展,可视化仿真和快速原形制造RPM已经成为CAD/CAM仿真领域的热点.文中介绍了RPM可视化仿真系统的总体结构和软件设计思想,为了实现数控机床加工零件产品的快速原形制造系统,提出了一种基于AutoCADRl4、VisualC 6.0和OpenGL语言的RPM技术实现方案.该方案利用VisualC 6.0作为系统开发平台,使用目前通用的3D图形API标准,可以方便地将AutoCADRl4输出的STL文件利用OpenGL进行三维真实感显示,并可以根据需要实现各种视图变换操作.最后给出了一个仿真结果,验证了该系统的性能.