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.     

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AutoCAD R14、Visual C＋＋6．0和OpenGL语言的RPM技术实现方案。该方案利用Visual C＋＋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AutoCAD R14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。     

一种开放式数控系统刀具运动轨迹验证方法

为了更准确的仿真五轴数控机床各运动轴的运动情况,提出一种开放式数控系统刀具运动轨迹验证方法.本方法从运动控制组件中采集运动控制数据,利用五轴机床机构运动学模型,将运动控制数据转换为工件坐标系下刀具的运动轨迹,并以三维线框方式显示.通过CNC系统与CAD系统STL模型数据的交换,实现了刀具运动轨迹与CAD设计模型的分析比较,并设计了轨迹误差计算模型,可以定量分析仿真的刀具运动轨迹.最后通过实验验证了方法的正确性.     

通过Three.js引擎加载STL模型

介绍了STL模型的基本知识和通过Three.js引擎加载STL模型的具体步骤.STL模型的基本知识主要介绍其概况及格式解析方法,对通过Three.js引擎加载STL模型进行了深入探讨.STL格式的模型,其将三角形作为基础图形,对模型表面进行组织,十分适合在电子设备上进行绘制.     

单量子比特系统状态的在线估计

针对具有退相干效应与测量反馈随机噪声的随机开放量子系统, 采用对状态影响较弱的连续弱测量在线获取一系列状态的部分信息, 实现量子状态的在线估计.由泡利矩阵构造初始测量算符, 并推导出在线的随时间变化的测量算符; 基于压缩传感理论来减少测量次数; 采用最小二乘优化算法对自由演化中的量子密度矩阵状态进行重构, 完整地给出了量子态在线估计的过程.所提出的在线量子态估计方案, 在一个量子位系统上进行了系统仿真实验.数值仿真实验结果表明, 在满足压缩传感理论的条件下, 仅需2次连续弱测量所得到的测量值之后, 就可以高精度地实现在线变化的单比特量子密度矩阵估计.     

基于AVL树的STL模型快速拓扑重建算法

STL数据格式是目前广泛应用于CAD系统中进行数据交换的标准格式之一。使用三角面片表示实体表面信息。但STL数据格式具有数据冗余和缺乏拓扑信息的缺点,针对这一问题,本文采用半边数据结构,提出一种基于辅助AVL树的STL模型快速拓扑重建算法,能快速有效地去除冗余顶点及实现半边合并。     

基于立体视觉的在线实时测量系统设计与实现

为了满足深空探测器实时测量天体表面形貌的需求,设计并实现了一套基于立体视觉的在线实时测量原型系统。该系统通过立体相机实时获取空间天体的立体影像,利用每次观测的一组立体影像来重建其局部表面形状;再对每次重建的局部模型进行连接,得到空间天体完整的表面形貌模型。通过仿真实验验证了该系统的可行性,数据处理的速度与精度可以满足对深空目标进行实时测量的需要。     

基于CAD/CAE的卡扣模具快速设计与优化

为提高塑料卡扣模具设计的速度,利用ImageWare对塑料卡扣进行点云数据处理、特征线网格划分和曲面重构;将重构的塑料卡扣模型导入UG,借助UG的曲面修复功能缝合不连续的曲面,并以STL格式保存;利用UG的Mold Wizards模具设计模块,根据已保存的STL格式卡扣模型建立模具装配模型,设计分型面,生成模具成型零件的三维实体模型;用Moldflow/MPI进行塑料卡扣注射成型分析.结果表明采用优化后的模具设计参数与实验结果基本吻合。     

催化剂颗粒浓度在线检测系统的研究与开发

基于Mie光散射理论,开发了石油炼化装置烟气催化剂颗粒浓度在线检测系统,采用了基于最小二乘支持向量机(least square support vector machine,LS-SVM)的软测量技术.利用LS-SVM优良的非线性映射和强大的泛化能力,建立了颗粒浓度的软测量模型,通过LS-SVM的学习和支持向量的自适应更新,实现催化剂颗粒浓度的最佳估计.仿真和实际运行结果表明所开发的监测系统可对烟气催化剂颗粒浓度进行有效测量,其测量精度比经验公式提高4.2倍.     

基于STL文件和3DS文件的几何模型重建方法研究

针对目前复杂几何模型在三维仿真中建模困难的现实,提出一种三维重建方法。本文采用Visual C＋＋编程语言,对几何模型的STL和3DS两种格式的数据文件设计相应的读取程序;以OpenGL图形接口为基础设计几何模型绘制程序,实现三维几何模型的重建。     

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.     

A grid generator for 3-D explosion simulations using the staircase boundary approach in Cartesian coordinates based on STL models

In this paper, an automatic grid generator based on STL models is proposed. The staircase boundary treatment is implemented to handle irregular geometries and the computation domain is discretized using a regular Cartesian grid. Using the grid generator, staircase grids that are suitable for fast and accurate finite difference analysis could be generated. Employing the slicing algorithm in RP technologies [1], the STL models are sliced with a set of parallel planes to generate 2D slices after the STL files obtained from a CAD system undergo topology reconstruction. To decrease the staircase error (increase accuracy) and enhance working efficiency, the cross-section at the middle of the layer is taken to represent the cross-section of whole layer. The scan line filling technique of computer graphics [2] is used to achieve grid generation after slicing. Finally, we demonstrate an application of the introduced method to generate staircase grids, which allows successful FDM simulation in the field of explosion. The example shows that the automatic grid generator based on STL models is fast and gives simulation results that are in agreement with practical observations.     

Viewer,converter and preprocessor for smart machining process using an industrial robot

In this paper, viewer and converter softwares are presented for smart machining process using an industrial robot. The viewers for NC, CLS, DXF and STL files illustrate their surface representation with normal direction vectors. For example, the DXF is a data format developed by Autodesk to realize data interoperability among different makers’ CAD systems. The STL means Stereolithography which is a file format proposed by 3D Systems and recently is supported by many design tools and CAD/CAM softwares. In addition, the converters for DXF and STL files generate the corresponding CLS files with normal direction vectors for machining. Further, the proposed preprocessor allows the developed machining robot to work based on information included in STL files. The convenience and user-friendliness of the proposed integrated system are confirmed through experiments of viewing, converting and machining.     

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。     

基于OpenGL三维物体建模方法的研究与实现

使用OpenGL可以对读入的STL几何模型进行三维真实感渲染、视角变换、显示缩放、光照设置及鼠标拾取等。本文介绍了一种基于OpenGL的三维物体建模方法,分析了基于该方法设计相应软件的体系结构,并着重探讨了STL文件的载入及视角变换等关键技术。     

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。     

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.     

基于STL文件的曲面网格重建算法

利用STL文件的数据相关性以及平衡二叉(AVL)树的数据搜索效率仅与树的高度相关的特性,提出一种高效的三角形曲面网格模型重建算法。该算法可以解决STL文件存在大量的冗余、使用效率不高等问题。实验结果证明,与基于AVL树的顶点快速聚合算法相比,该算法的重建效率更高。