基于特征的车身梁结构过渡区域自动建模研究
摘要
车身上包含大量的梁结构。如果将梁的截面结构和梁结构间的过渡区域建立起直接的基于特征的参数化关系,那么将大大地缩短此类结构的三维建模及修改时间,为进一步提高产品的改进和优化效率提供了便利。
本文主要讨论了在UG/NX6软件平台上进行的“基于特征的车身梁结构过渡区域自动建模”模块的开发工作。
在研究初期,根据手动生成梁结构过渡区域的过程,提炼出整体设计思路,并就各个步骤的具体实现方法进行了较为细致的阐述,论证了其可行性。
研究工作中综合应用了UG/NX软件提供的包括UG/Open API,KF,UDU等在内的多种开发工具。对于在UG/NX平台下,创建特征的方法和过程进行了详细的阐述。其中对该模块的界面设计还运用了UG/NX6版本上最新的Block Styler开发模块,这是一种全新的尝试。
本文的研究是基于某汽车厂商提出的实际问题而进行的,该功能已经通过了需求方的测试和验证。通过在梁的截面结构和过渡区域之间建立起直接的特征参数化关系,实现了过渡区域随着梁结构截面形式的改变能够进行自适应调整,从而减少了设计人员对模型的修改工作,缩短了产品的开发周期,降低了设计成本。
With the body design in the vehicle development process becoming increasingly important, people raised higher demands on the quality of auto body model and modify aspect. If use the general of CAD tools, it is a time-consuming and complicated process, when the designers want to obtain a detailed description of the auto body of the geometric structure of the digital model. In order to make this process becomes quick and reliable, many designers are looking for all kinds of improved design method. Auto body as much as possible to achieve the parameters of the modeling process, is one of the ways.
Beam structure is the main structural component of the body. Beam structure in different regions of the transition generation is a type frequently encountered situations in a auto body three-dimension modeling process. However beam structure is often vastly different, so the manual creation of regional transition process is very complex and cumbersome. Moreover, once the beam changes in the structure, associated with the transition region need to re-create the design staff, which consume a great deal of valuable time. This repeated process is serious constraints on the model update speed and affects the efficiency of product development. If this part of the modeling process can achieve automatic modeling based on the characteristics of the process, it will greatly enhance the work efficiency of the design. At the same time it plays an important role in facilitating the ultimate realization of the whole auto body of parametric modeling. Therefore, it is of great significance to research on feature-based automatic modeling of the body beam structure of the transition region.
In this paper, with UG / NX software platform, the combination of UG / Open API, KF, Block Styler, and other development tools, developed a body beam structure of the transition region based on the characteristics of the parameters of creation modules. As a global leader in PLM software development and services company, UG / NX software development a lot of automotive design automation module. Faced with the current users of the requirements of the three-dimensional model cars continuously improve, it raises the concept of body structure CVA (Concept Vehicle Architecture project), as envisaged eventually to the full realization of the entire body design parameter. This paper discusses the Transition Module, it is on this background, a combination of the practical requirements of vehicle manufacturers, was proposed.
The main purpose of this paper is: avoid the cumbersome body beam structure transition region in the manual process of creating and realizing this process based on the characteristics of parametric design, changes in the structure of the beam, associated with the transition region can be adjusted automatically. At the same time, the use of features and the creation process of the features in UG/NX software is summarized.
According to the above-mentioned purposes, the paper launched the following main aspects:
⑴Familiar with the manual creation of the regional body beam structure of the transition process, and create derived from the main steps.①beam structure will be connected into the edge of bridge in accordance with a reasonable order.②through two adjacent bridge curves, as well as bridging the section line between them creating a transition surface.③from the remaining section of the bridge and the closure of the region surrounded by N-sided Surface create surface.④sew the various surface together to become a whole.
⑵Design the overall process framework, by extracted from the main steps of manual method. The work needed to complete, as well as the algorithm in the steps is discussed, including the selected section of the bridge online unified point of order, determine the section line between reasonable direction, create different beam cross-section of the bridge curve, the criteria of adding bridging point were analyzed when cross-section of the bridge between the number of points not the same ,need to add auxiliary bridge, in accordance with certain rules, the transition will be divided into regional side and bottom two types, then use the creation of different surfaces methods in UG / NX software to generate surfaces.
⑶In UG/NX6 platform, completed the implementation of procedures , by integrating application of a variety of development tools. Use the latest software interface development module to design the interface.
⑷This paper made a summary on the characteristics of the application software advantages and characteristics of the process of creating in NX software. NX software features can be intuitively understood as a model of the navigation tree’s every step, every node. Feature provides a method of object-oriented design approach. It can be inside the packaging of various attributes and function , so it can be extended to include engineering significance of the geometric prototype. NX software to create characteristics of the process, summed up the following basic steps:
(1) In accordance with the specific requirements for the design of new feature functions.
(2) Definition of the characteristic parameters of the new category.
(3) To achieve the necessary characteristics of the function.
(4) To set the characteristics of the necessary attributes.
(5) To create and edit features to implement characteristics of the function.
(6) Implementation interactive between interface, UG / OPEN and KF.
In addition, this paper, the actual operation of the module has done examples, including the creation of Transition features, edit Transition features in detail, also on the characteristics of the adaptive features of the application.
This paper focused on in the car body modeling process solving on different beam structure with the transition region between the characteristic parameters of the relationship. Using NX software platform, Beam structure will be the formation of regional transition process designed to be a feature-based automatic process modeling. The function can guarantee that the transition region with the beam and changes in the structure of automatic adjustment. The development of the functional modules, can avoid in the car design stage, due to changes in the structure of the beam need to re-create the tedious process of the transition region. It has laid the foundation to improve efficiency and enhance the analysis of the concept of auto body accuracy. In addition, using the latest UG/NX6 software interface development tools, and the creation of the characteristics of the process are described in this paper. It has some role in guiding on the application of a body design of this software in terms of researchers.
本文主要讨论了在UG/NX6软件平台上进行的“基于特征的车身梁结构过渡区域自动建模”模块的开发工作。
在研究初期,根据手动生成梁结构过渡区域的过程,提炼出整体设计思路,并就各个步骤的具体实现方法进行了较为细致的阐述,论证了其可行性。
研究工作中综合应用了UG/NX软件提供的包括UG/Open API,KF,UDU等在内的多种开发工具。对于在UG/NX平台下,创建特征的方法和过程进行了详细的阐述。其中对该模块的界面设计还运用了UG/NX6版本上最新的Block Styler开发模块,这是一种全新的尝试。
本文的研究是基于某汽车厂商提出的实际问题而进行的,该功能已经通过了需求方的测试和验证。通过在梁的截面结构和过渡区域之间建立起直接的特征参数化关系,实现了过渡区域随着梁结构截面形式的改变能够进行自适应调整,从而减少了设计人员对模型的修改工作,缩短了产品的开发周期,降低了设计成本。
With the body design in the vehicle development process becoming increasingly important, people raised higher demands on the quality of auto body model and modify aspect. If use the general of CAD tools, it is a time-consuming and complicated process, when the designers want to obtain a detailed description of the auto body of the geometric structure of the digital model. In order to make this process becomes quick and reliable, many designers are looking for all kinds of improved design method. Auto body as much as possible to achieve the parameters of the modeling process, is one of the ways.
Beam structure is the main structural component of the body. Beam structure in different regions of the transition generation is a type frequently encountered situations in a auto body three-dimension modeling process. However beam structure is often vastly different, so the manual creation of regional transition process is very complex and cumbersome. Moreover, once the beam changes in the structure, associated with the transition region need to re-create the design staff, which consume a great deal of valuable time. This repeated process is serious constraints on the model update speed and affects the efficiency of product development. If this part of the modeling process can achieve automatic modeling based on the characteristics of the process, it will greatly enhance the work efficiency of the design. At the same time it plays an important role in facilitating the ultimate realization of the whole auto body of parametric modeling. Therefore, it is of great significance to research on feature-based automatic modeling of the body beam structure of the transition region.
In this paper, with UG / NX software platform, the combination of UG / Open API, KF, Block Styler, and other development tools, developed a body beam structure of the transition region based on the characteristics of the parameters of creation modules. As a global leader in PLM software development and services company, UG / NX software development a lot of automotive design automation module. Faced with the current users of the requirements of the three-dimensional model cars continuously improve, it raises the concept of body structure CVA (Concept Vehicle Architecture project), as envisaged eventually to the full realization of the entire body design parameter. This paper discusses the Transition Module, it is on this background, a combination of the practical requirements of vehicle manufacturers, was proposed.
The main purpose of this paper is: avoid the cumbersome body beam structure transition region in the manual process of creating and realizing this process based on the characteristics of parametric design, changes in the structure of the beam, associated with the transition region can be adjusted automatically. At the same time, the use of features and the creation process of the features in UG/NX software is summarized.
According to the above-mentioned purposes, the paper launched the following main aspects:
⑴Familiar with the manual creation of the regional body beam structure of the transition process, and create derived from the main steps.①beam structure will be connected into the edge of bridge in accordance with a reasonable order.②through two adjacent bridge curves, as well as bridging the section line between them creating a transition surface.③from the remaining section of the bridge and the closure of the region surrounded by N-sided Surface create surface.④sew the various surface together to become a whole.
⑵Design the overall process framework, by extracted from the main steps of manual method. The work needed to complete, as well as the algorithm in the steps is discussed, including the selected section of the bridge online unified point of order, determine the section line between reasonable direction, create different beam cross-section of the bridge curve, the criteria of adding bridging point were analyzed when cross-section of the bridge between the number of points not the same ,need to add auxiliary bridge, in accordance with certain rules, the transition will be divided into regional side and bottom two types, then use the creation of different surfaces methods in UG / NX software to generate surfaces.
⑶In UG/NX6 platform, completed the implementation of procedures , by integrating application of a variety of development tools. Use the latest software interface development module to design the interface.
⑷This paper made a summary on the characteristics of the application software advantages and characteristics of the process of creating in NX software. NX software features can be intuitively understood as a model of the navigation tree’s every step, every node. Feature provides a method of object-oriented design approach. It can be inside the packaging of various attributes and function , so it can be extended to include engineering significance of the geometric prototype. NX software to create characteristics of the process, summed up the following basic steps:
(1) In accordance with the specific requirements for the design of new feature functions.
(2) Definition of the characteristic parameters of the new category.
(3) To achieve the necessary characteristics of the function.
(4) To set the characteristics of the necessary attributes.
(5) To create and edit features to implement characteristics of the function.
(6) Implementation interactive between interface, UG / OPEN and KF.
In addition, this paper, the actual operation of the module has done examples, including the creation of Transition features, edit Transition features in detail, also on the characteristics of the adaptive features of the application.
This paper focused on in the car body modeling process solving on different beam structure with the transition region between the characteristic parameters of the relationship. Using NX software platform, Beam structure will be the formation of regional transition process designed to be a feature-based automatic process modeling. The function can guarantee that the transition region with the beam and changes in the structure of automatic adjustment. The development of the functional modules, can avoid in the car design stage, due to changes in the structure of the beam need to re-create the tedious process of the transition region. It has laid the foundation to improve efficiency and enhance the analysis of the concept of auto body accuracy. In addition, using the latest UG/NX6 software interface development tools, and the creation of the characteristics of the process are described in this paper. It has some role in guiding on the application of a body design of this software in terms of researchers.
引文
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[14] Ding Yi,JiLin University,Some Studies on Workflow & Method and Correlative Software Developing Techniques for Conceptual Body Design Based on KBE and DFM,2004,CHARPER 4
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[17] Nicklas Bylund,Models,Methods and Tools for Car Body Development,Divison of Computer Aided Design Lulea University of Technology SE-971 87,2002,P13
[18] Naesung Lyu,Kazuhiro Saitou,Decomposition-Based Assembly Synthesis of Space Frame Structures Using Joint Library,Journal of Mechanical Design,Jan,2006,P57-64
[19] http://www.plm.automation.siemens.com/en_us/products/nx/
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[3] 卢海峰,李军,基于特征体系的车身结构模型研究,计算机仿真,2004.12,P220-222
[4] 孟俊焕,王卫东,马洪新,基于虚拟现实技术的汽车开发应用研究,农业装备与车辆工,2006 第 2 期,P11-13
[5] 张德超,虚拟技术在汽车全生命周期的应用,天津汽车,2006 年 02 期,P29-33
[6] 宗振奇,虚拟技术在汽车工业中的应用,沈阳大学学报,2005 年 06 期,P49-52
[7] 丁祎,尹伟,胡平,应用虚拟技术加快汽车开发进程,吉林大学学报(工学版),2002 年 7 月,P92-93
[8] 张亮有,马卫军,郑荣,基于特征的参数化三维造型技术及其应用,山西科技2003 年第 5 期,P30-31
[9] 应济,张万利,基于特征的参数化建模技术的研究,机电工程,2003 年第 4 期,P4-7
[10] 唐良红,孙立镌,王树胜,基于特征的参数化设计和实体模型编辑的研究,工程图学学报,1999 年第 2 期,P71-77
[11] 饶金通,董槐林,姜青山,基于特征的参数化高效建模技术,厦门大学学报(自然科学版),2006 年 3 月,P191-195
[12] 张跃宏,沈金良,CAD 应用中基于特征的参数化设计,交通与计算机, 2003年第 3 期,P51-53
[13] Liu Su,Qian Xiaofeng,Reasearch on Parametric Modeling System Based on Feature,Transactions of Nanjing University of Aeronautics &Astronautics,Dec. 1999,P161-162
[14] Ding Yi,JiLin University,Some Studies on Workflow & Method and Correlative Software Developing Techniques for Conceptual Body Design Based on KBE and DFM,2004,CHARPER 4
[15] Hou Wen-bin,Hu Ping,Liu Da-you,An Intelligent System for Vehicle Structure Concept Design,Journal of Jilin University Engineering and Technology Edition,July,2006,P88-91
[16] Chi Rui-feng,Hou Wen-bin,Cai Shi-min,Hu Ping,A parameterized Design and CAE Scheme of Concept Auto-body Structure , Journal of Jilin University Engineering and Technology Edition,July,2006,P191-195
[17] Nicklas Bylund,Models,Methods and Tools for Car Body Development,Divison of Computer Aided Design Lulea University of Technology SE-971 87,2002,P13
[18] Naesung Lyu,Kazuhiro Saitou,Decomposition-Based Assembly Synthesis of Space Frame Structures Using Joint Library,Journal of Mechanical Design,Jan,2006,P57-64
[19] http://www.plm.automation.siemens.com/en_us/products/nx/
[20] 崔洪斌等编著,计算机辅助设计基础及应用,清华大学出版社,2002,P90-92
[21] 陈鑫主编,车身 CAD 技术,人民交通出版社,2005.09,P30-34
[22] 施法中编著,计算机辅助几何造型设计与非均匀有理 B 样条,高等教育出版社,2001,P28-29,P41-42
[23] 兰凤崇编著,汽车车身计算机辅助造型设计,吉林科技出版社,1992,P99-100
[24] 许智钦,孙长库编著,3D 逆向工程技术,中国计量出版社,2002.03,P45
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