双光子微细加工系统数据处理软件的实现

双光子微细加工技术是一项新型的三维微细加工技术。提出以STL格式作为典型CAD软件和双光子加工数据处理软件的中介格式,并以VisualC 6.0开发了基于MFC的该软件,由STL文件读入及显示、STL文件正确性检验、分层、轮廓线优化、扫描路径填充等模块组成。软件操作简单,使用可靠。     

Development of post-processor approach for an industrial robot FANUC R2000<Emphasis Type="Italic">i</Emphasis>C

In this paper, a post-processor for the industrial robot FANUC R2000iC is introduced. Without going through the conventional teaching process, the post-processor regularly generates a rigorous robotic program from cutter location source data called CLS data. The CLS data are easily made through the main process of CAD/CAM, so that a promising data interface is realized between the industrial robot and CAD/CAM. The effectiveness is evaluated through simulations of trajectory following and also through an actual machining experiment of foamed polystyrene with a complex shape.     

飞行器几何数据库与CAD软件数据交换问题研究

飞行器几何数据入库的关键,是在对图形文件结构分析研究的基础上,开发出CAD软件的图形数据和数据库之间的接口程序,使得图形数据和数据库数据可以自由交换。论文研究了IGES文件格式和DXF文件格式的详细结构,开发出具有IGES文件和DXF文件入库与出库功能的飞行器几何数据库管理系统软件。     

Program design of STL machine graphics realistic system

This topic is based on Auto CAD graphic input environment.It takes the STL format graphic files as the data exchange interface to do the research of STL interactive 3D realistic graphics displaying content.Through the analysis of the STL file format,in VC++6.0 programming environment,class if stream in the standard IO library was used for object class definition.And get line functions in the string class were called to read and bind STL file line by line.In data processing module,draw triangles in Open GL programming technology was applied to realize the visual display of the STL graphics,with the corresponding 3D entity data generated.Open GL graphics processing technologies were applied to display 3D graphics from STL files input or realistic program module,which contain the graphic transformation,light,materials,et al.Test reports were shared based on the test of the application system.Finally the program design of STL graphics realistic display system was completed based on research work,which has certain theoretical and practical significance in the aspect of engineering application.     

Open architecture of CNC system research based on CAD graph-driven technology

Based on CAD graph-driven technology, a kind of novel open architecture CNC system is put forward and designed together with the key hardware “PC+PMAC controller”. The intelligent CNC system software including several function modules is developed under Visual C++6.0 environment. Graphic feature identification and geometric parameter extraction from CAD-part-drawing saved as DXF format are performed to control the relative motion between cutting tool and part. The ant-colony algorithm is applied to auto-optimize the cutting tool paths in machining process. The experiment results of a plane engraving machining example show that the proposed method is feasible, and the entire machining process no longer needs NC programming. The efficiency of CNC machining is improved greatly, and the true intelligent CNC machining can be realized when the advanced programming technologies are integrated in one system according to the proposed conception.     

STL、DXF等通用文件格式图形的真实感显示

以AutoCAD作为图形输入环境,以STL、DXF等格式的图形文件作为数据交换接口,对图形进行交互式立体显示,通过分析文件格式,在Visual C 6.0编程环境下获取文件中的二、三维图形信息,对其中基于回转体的二维图形进行三维旋转造型,生成三维实体数据。并应用OpenGL图形处理技术对输入的三维图形实现真实感显示,进行变换、光照、材质等方面的处理。     

Machine path generation for the SIS process

Because of the differences in the nature of rapid prototyping (RP) processes, there is no standard machine path code for them. Each RP process, based on its characteristics and requirements, uses the standard CAD file format to extract the required data for the process. Selective inhibition of sintering (SIS) is a new layered fabrication method based on powder sintering. Like other RP systems, SIS needs a specialized machine path generator to create an appropriate machine path file. Machine path (i.e., boundary path and hatch path) should produce the printing pattern that enables the SIS machine user to easily remove the fabricated part from the surrounding material. A new machine path algorithm, which generates appropriate boundary and hatch paths for the SIS process is proposed. The new machine path generator provides the ability to process CAD models of any size and complexity, the ability for machine path verification before sending the file to the SIS machine, and the ability to fix the possible STL files disconnection errors. In this system, very large STL files can be processed in a relatively small computer memory. The system has been successfully tested on STL files as large as 200 MB. The generated path files have been used in fabrication of several parts by the SIS process.     

建筑安装工程图纸对象自动识别方法的研究

针对当前主要依靠人工进行识别的现状,提出一种计算机自动识别建筑安装工程图纸中电气构件的方法.首先利用DXF文件读取图形信息,根据电气构件图形特征,删除DXF文件中的冗余图形信息,并将DXF文件转为图像格式,在图像中利用图像分割技术读取全部的电气构件数据.实验仿真结果表明该方法快速、有效.     

激光直接制造和再制造中的三维CAD模型直接分层技术

在分析SolidWorks软件平台下CAD模型数据的内部表达方法以及拓扑信息和几何信息提取方法的基础上,研究三维CAD模型直接分层技术.对SolidWorks进行二次开发,调用SolidWorks应用程序接口函数中的曲面一曲面求交函数对CAD模型曲面与分层平面求交,得到的交线首尾相连形成轮廓轨迹;同时研究了光栅填充扫描算法及程序实现.为实现切片数据的通用化,设计了记录切片数据的文件格式,用直线、圆弧或圆描述分层轮廓.对上述的直接分层不仅进行了软件模拟,还用于直接制造.制作的试件与STL间接分层试件比较结果表明,采用直接分层的试件的精度和表面质量优于STL间接分层.     

概念图形草绘设计技术研究

针对概念草图的输入输出问题,采用了基于草绘输入的交互式图形设计方法,实现了单笔划草绘轨迹主动分段识别与规整方法;运用了基于笔式手势的草图编辑方法,并将概念草图以DXF的格式输出,实现与现有CAD系统之间的集成.根据手势设计原则以及草图编辑的需要,定义并实现了选择、删除、移动等10种手势,同时采用感知器线性分类方法对手势进行识别.实例表明:手势编辑模式能够改善传统编辑方式在自然性与智能性方面的不足.     

基于DXF文件的数控自动编程中的路径优化

分析了 DXF 文件结构并在此基础上简要介绍了需要提取的信息。针对无序的加工路径使得空刀路径长度过大的情况,提出了一种基于遗传算法的路径优化算法。并比较了路径优化前后路径中空刀路径长度,可以得出经算法优化后得到的路径空刀路径明显减少,从而使得加工效率得到提高。     

用VC实现基于DXF文件的AutoCAD数据共享接口

较为详细地介绍了DXF文件格式,并由此推导出AutoCAD外部数据接口的框架。使用VisualC＋＋语言实现了基于DXF文件的AutoCAD数据接口,建立了自主应用软件与AutoCAD之间的共享数据通道。     

DXF格式文件在缝制数据编制软件中的应用

在数控缝制数据编制软件中,为了实现对AutoCAD软件生成的复杂图案文件进行输入和编辑的功能,研究DXF数据文件的格式,结合VC＋＋6.0的图形图像处理技术,编写了相应的数据接口程序,完成了对DXF文件数据信息的提取。     

基于CAD信息获取的ERP辅助软件系统实现

通过对AutoCAD的DXF文件格式进行分析,设计了一种获取CAD文件信息的软件系统.与厂家原有的ERP系统集成,较好地解决了企业图纸信息的管理问题,简化了企业对图纸信息管理的复杂性,保证了企业信息的一致性,提高了图纸信息的重用效率.同时也使ERP纳入了产品数据管理PDM功能.     

基于压缩体素模型的快速成型直接切片算法*

基于STL文件模型的间接分层切片算法存在缺乏拓扑信息, 面误差诊断修复困难等问题,结合压缩表示形式的体素模型特点,提出了一种新的基于压缩体素模型直接切片分层优化算法.该算法利用Dexel模型记录的Dexel射线和物体交点所表达的物体表面点位置,通过设定分层平面厚度等参数获得截面轮廓数据,生成可直接适用于快速成型系统的共用层接口CLI文件.该算法在虚拟油泥造型系统中得到了应用,实验结果表明算法稳定、分层效果良好.     

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.     

基于DXF图形文件的加工控制系统

在分析图形交换文件的特点的基础上,提出一种用于预定轨迹加工的自动控制系统,并详细介绍了系统的设计原理、硬件组成和软件开发。该系统以CAD图形来描述加工轨迹,加工指令的产生和加工过程的控制则由系统自动实现,解决了设计与加工的一体化问题。     

基于NURBS曲线的STL模型截面轮廓平滑处理技术研究

由于STL文件格式的容易生成且不需要复杂的CAD系统支持，已经发展成为快速成型制造领域数据交换的准标准；但是STL模型的精度与其数据文件的尺寸之间存在严重的矛盾，为了在较小的STL文件下得到较高的轮廓精度，本文提出了一种基于三次NURBS曲线STL模型截面轮廓的重构技术，通过设置直线阈值和转角阈值的方法，分段拟合STL截面轮廓数据，使其截面轮廓具有更好的平滑度和更高的精度。     

Integrated reverse engineering and rapid prototyping

Reverse engineering is a methodology for constructing CAD models of physical parts by digitizing an existing part, creating a computer model and then using it to manufacture the component. When a digitized part is to be manufactured by means of rapid prototyping machines such as stereolithography apparatus (SLA) and selective laser sintering equipments (SLS), etc., it is not necessary to construct the CAD model of a digitized part. This will be described by the proposed novel method which can construct STL file (the de facto file format for rapid prototyping machines) directly from digitized part data. Further more, the STL file can even be constructed in a way that significant data reduction can be achieved at the users' discretion.