共查询到20条相似文献,搜索用时 187 毫秒
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构造细分曲面的初始控制网格是利用细分曲面技术进行自由曲面造型过程中的一个重要问题。该文提出一种基于边界曲线的初始控制网格构造方法,其中包括曲线的离散化、基曲面边界回路识别以及回路内控制网格的生成等过程,以实现任意拓扑结构边界曲线的控制网格的生成。该方法在多种不同的曲线模型上进行了测试,简化了曲面造型的网格生成过程,可有效提高自由曲面的设计效率。 相似文献
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程东风 《机电产品开发与创新》2007,20(1):194-196
在CAD/CAM技术中,创建曲面是用来构建模型以及产生加工路径和生成加工程序的重要工具和手段。创建网格曲面是Mastercam X版本的新增功能,在模具三维造型设计中应用该功能可以创建复杂的空间自由曲面,本文通过实例介绍创建网格曲面的方法。 相似文献
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基于网格曲面模型的等残留刀位轨迹生成方法 总被引:4,自引:1,他引:3
三角网格曲面因其快速灵活、拓扑适应能力强等优点,在与制造业密切相关的航空航天、汽车、造船以及模具等工业领域得到越来越广泛的应用。针对网格曲面加工截面线型路径与边界不一致性等问题,提出一种保持边界一致的等残留刀位轨迹生成方法。该方法以减少抬刀、路径转接为目的,并综合考虑刀具轨迹几何与运动力学性能。首先对网格曲面局部区域进行精确拟合,进而给出一种网格曲面上曲线的偏置方法。以此为基础,对网格模型的边界轮廓进行等残留偏置,从而生成精确的刀位轨迹。实例表明该轨迹生成方法简便、可靠,具有良好的边界一致性,并可显著提高加工的效率和精度。 相似文献
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采用保特征的模型分解方法将STL模型分割为多个子域,并为每个子域构建参考平面,将一类基于映射思想的前沿推进曲面网格生成算法应用于子域网格生成.在子域上构建G1连续的三角Bemstein-Bézier曲面,利用曲面的方向导矢计算子域的黎曼度量,在黎曼空间生成参数平面网格,以消除映射畸变.考虑曲面曲率和邻近特征计算边界采样点尺寸,利用采样点的Delaunay三角化为背景网格建立几何自适应尺寸场,通过尺寸场光滑化确保不同尺寸网格之间的合理过渡.数值试验表明,算法能针对复杂的STL模型生成高质量的自适应网格. 相似文献
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复杂曲面模具测量、造型与加工一体化系统——3MS 总被引:3,自引:0,他引:3
介绍了复杂曲面模具测量、造型与加工一体化系统(3MS)的结构和主模块功能,重点分析了CAM模块的设计思想。该系统是基于复杂曲面模具测量、造型和制造一体化的概念而开发的,其核心包括散乱数据的三角划分及其网格优化、三角曲面造型和刀具加工轨迹生成等模块。 相似文献
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W. Hu W. Yang Y. Xiong 《The International Journal of Advanced Manufacturing Technology》2005,26(11-12):1362-1369
Reconstructing exact topology mesh from data points is one of the most important tasks in the fields of industrial CAD/CAE/CAM, computational vision and reverse engineering. In this paper, a deflation algorithm that integrates an adaptive mesh and physical constraint model is presented for the 3D reconstruction of geometric-closed shape (genus 0) from unorganized data points. First, an initial mesh is formed using the Delaunay algorithm. Second, an asymptotic deforming performance is accomplished to deflate initial mesh towards the local concave boundary step-by-step. In this phase, a physical constraint model of coupled particle systems based on particle dynamics and Newtonian law of motion is constructed, and the model dynamically controls mesh deformation as a behavior constraint. To guarantee that the resultant mesh is homeomorphous to the original surface of data points, a continuously deforming mechanism, visibility cone and collision-detecting criterions are designed. At last, experimental results in reverse engineering which supports the usefulness of this method for reconstruction . 相似文献
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Feature-based non-manifold modeling system to integrate design and analysis of injection molding products 总被引:1,自引:0,他引:1
Sang Hun Lee 《Journal of Mechanical Science and Technology》2009,23(5):1331-1341
Current CAE systems used for both the simulation of the injection molding process and the structural analysis of plastic parts
accept solid models as geometric input. However, abstract models composed of sheets and wireframes are still used by CAE systems
to carry out more analyses more efficiently. Therefore, to obtain an adequate abstract model, designers often have to simplify
and idealize a detailed model of a part to a specific level of detail and/or abstraction. For such a process, we developed
a feature-based design system based on a non-manifold modeling kernel supporting feature-based multi-resolution and multi-abstraction
modeling capabilities. In this system, the geometric models for the CAD and CAE systems are merged into a single master model
in a non-manifold topological representation, and then, for a given level of detail and abstraction, a simplified solid or
non-manifold model is extracted immediately for an analysis. For a design change, the design and analysis models are modified
simultaneously. As a result, this feature-based design system is able to provide a more integrated environment for the design
and analysis of plastic injection molding parts.
This paper was recommended for publication in revised form by Associate Editor Tae Hee Lee
Sang Hun Lee received his B.S., M.S., and Ph. D. degrees in Mechanical Design and Production Engineering from Seoul National University,
Korea, in 1986, 1988, and 1993, respectively. Dr. Lee is currently a Professor at the School of Mechanical and Automotive
Engineering at Kookmin University in Seoul, Korea. His research interests include CAD/ CAM, human-centered design and engineering,
digital human modeling and simulation, computer-aided automotive design and manufacturing., and computer-aided tooling design. 相似文献
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Aditya T. Kasarekar Nathan W. Bolander Farshid Sadeghi Spyros Tseregounis 《International Journal of Mechanical Sciences》2007,49(6):690-703
This paper presents a numerical model that maps the evolution of contact pressure and surface profile of Hertzian rough contacting bodies in fretting wear under partial slip conditions. The model was used to determine the sliding distance of the contacting surface asperities for one cycle of tangential load. The contact pressure and sliding distance were used with Archard's wear law to determine local wear at each surface asperity. Subsequently, the contact surface profile was updated due to wear. The approach developed in this study allows for implementation of simulated and/or measured real rough surfaces and study the effects of various statistical surface properties on fretting wear. The results from this investigation indicate that an elastic–perfectly plastic material model is superior to a completely elastic material model. Surface roughness of even small magnitudes is a major factor in wear calculations and cannot be neglected. 相似文献
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为提高塑件生产质量,研究了CAE技术应用于注射模设计,论述了该技术的优点和意义;结合具体塑件,在浇注、冷却系统确定的前提下,CAE分析能够模拟注射过程,以流动、冷却和翘曲分析为例,分析结果以3D彩图形式给出,形象直观.通过应用CAE分析克服了以往只有在试模中才会发现的问题,缩短模具设计、制造周期,优化了注射模设计,提升了塑件质量. 相似文献
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一种复杂曲面展开的通用算法 总被引:1,自引:0,他引:1
提出了一种基于几何展开/力学修正的复杂曲面展开的通用算法,实现复杂曲面的展开.首先,对三维曲面进行三角化,用三角片模型来表达三维曲面;然后,采用几何展开的方法将三维曲面展开为初始二维平面;最后,提出一种改进的能量法优化算法,建立能量模型,对初始展开平面进行优化,得到最终展开结果.由于采用了能量法对初始展开片面进行优化,曲面展开的精度较易控制,因此能够更有效地解决CAD/CAM中的曲面展开问题. 相似文献
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基于ANSYS的电热产品热场分析方法与应用 总被引:1,自引:0,他引:1
针对CAD\CAE软件的特点,给出了三维模型温度场分析的一般方法,并就CAD软件和CAE软件之间的数据交换问题提出了相应的解决方案。以电热产品为例,介绍了对具有内热源的三维稳态问题的分析流程和具体应用。 相似文献
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