反向工程应用现状及研究方向

近年来 ,反向工程作为一种新的产品设计思想和方法越来越广泛地用于工业领域 ,并取得了不少成果。本文全面地总结了反向工程的环节、目前的研究应用状况及现有系统的不足之处 ,进一步提出了今后反向工程的研究方向     

自动生成优化的拆卸序列的初始群体

研究废弃产品的拆卸序列问题。首先，提出建立装配体的干涉一自由矩阵，描述零件相互之间的空间关系。然后，提出一种新的计算模型，据此计算各个零件从装配体上可以拆卸下来的方向，从而确定拆卸序列在几何上的可行性。最后，提出自动生成优化的拆卸序列的初始群体的计算方法，从而有效地提高遗传计算最优装配体拆卸序列的搜索效率。通过一系列的实例验证，证明了提出的这套方法切实可行。     

基于逆向工程的电话机身的模具设计的研究

通过对某型电话机身的逆向工程及模具设计,详细阐述了反求过程中的数据测量、曲线曲面重构及反求模型的模具设计,采用了一种将逆向工程与EMX系统相结合的设计方法。与传统的设计方法相比,该方法为新产品的开发提供了更方便、快捷的途径,能大大缩短产品模具设计和制造周期。     

Improvement of reverse-engineered turbine blades using construction geometry

The paper reports the latest outcomes of using design-based reverse engineering on turbine blades. For a long time, the focus of the reverse engineering methods has been the trend toward higher accuracies and faster measurements. Authors introduce a different viewpoint which focuses on design intent of a part. How to reverse engineer a complex shape like a turbine blade is the subject of current research. The attempt toward taking advantage of the construction geometry behind a sample heavy duty turbine blade is thoroughly discussed in three phases. First phase consists of 2D analysis of the reference sections. Then, the stacking axis is introduced as an important non-tangible feature which has the main role to connect the sections in 3D in lean and tilt directions. The third phase uses the concept of blade twist to provide a constraint to define rotational position of the sections with respect to neighbor sections. All the three phases have been applied to different types of original and non-original products which are available in the gas turbine market. The presented comparisons show clearly that the new method of reverse engineering incorporating construction geometry and design intent of the part is quite useful and recognizes many features behind the external geometry which is impossible to follow by the previous conventional methods. The turbine blade 3D model resulted from this new method will have a smooth arc-based surface, straight stacking line passing through turbine axis with maximum section tilt of 0.2 mm and maximum section lean of 0.3 mm to original equipment manufacturer parts and linearly increasing stagger angle from hub to tip which are some of considerable improvements compared to conventional method.     

基于反求工程和激光快速成型技术的新型车轮开发

针对某型已有车轮，通过反求工程获得了其数据点云，在此基础上，根据新型车轮的安装及外观要求完成了改型设计。并通过激光快速成型技术制作了轮辐的木制原型，对不同的设计方案进行了评估和装配校验，从而大大地加快了新产品的开发速度。     

An Internet-based integrated product design environment. Part I: a hybrid agent and network architecture

During the past two decades, concurrent or collaborative engineering (CE) has presented new possibilities for successful product development. In addition, the advances in computer networks and information technology have brought engineering design context into a new era. As a promising approach to accommodate the radical pace of changes in the context of engineering design, agent technologies have been attracting public attention and are being used in an increasingly wide variety of applications. However, little attention has been paid to multi-agent system (MAS) frameworks for CE environments that enable systematic and timely design integrations in both hierarchical and heterarchical design topology. This is the first of a two-part paper proposing a MAS framework for integrated product design in a computer network-oriented CE environment. Part I first proposes a hybrid agent network architecture to develop lightweight, dynamic and large-scale distributed systems, and then proposes a hybrid agent architecture based on our finite state automata (FSA) formalism that can exhibit both hybrid behaviours and hybrid interactions. Finally, some ideas for building an integrated product design environment are presented using the proposed agent and network architecture. Part II discusses the applications of the proposed MAS framework to concurrent engineering design.     

基于逆向工程的空调遥控器三维模型设计研究

针对市场对家电产品开发周期日益苛刻的需求,为满足家电产品快速开发,快速更新的需要,以空调遥控器外形三维模型重建与再设计为例,从遥控器外形点云数据的快速测量、点云数据的处理、点云几何拓扑结构分析、主辅曲面重建以及结合新产品开发需求再设计遥控器三维模型结构等方面对家电产品的快速设计进行了研究。对基于逆向工程的家电产品三维模型快速设计方法进行了归纳,提出一种正、逆向设计相结合的产品三维模型快速设计方法。研究结果表明,基于逆向工程技术的再设计方法,有利于提高家电产品设计效率,为家电类产品的开发提供了一种方便、快捷的手段。     

逆向工程技术在某皮卡车身开发中的应用

介绍了逆向工程技术的基本理论知识和在实际应用过程中一些关键技术处理方法,并依托某皮卡车身开发的流程,具体阐明了逆向工程技术在车身 Class-A（造型）面和结构件设计过程中的实际应用方法,论述了逆向工程技术在某皮卡车身设计开发过程中的重要性。运用逆向工程技术可以大大缩短新产品开发周期,提高工作效率,是现在汽车工业领域最重要的产品设计方法之一,也是产品快速创新开发的重要途径。     

面向集成数据模型的逆向工程系统研究

在集成逆向工程系统研究现状的基础上,建立由数字化子系统、模型重构子系统和产品制造子系统三部分组成的面向集成数据模型的逆向工程系统框架结构.对系统实现的关键技术及系统集成的数据转换技术进行研究,并重点介绍实现远程逆向工程技术的方法.通过应用实例验证该集成系统可有效地缩短产品制造周期、降低产品设计及开发成本.     

The Pre-Processing of Data Points for Curve Fitting in Reverse Engineering

Reverse engineering has become an important tool for CAD model construction from the data points, measured by a coordinate measuring machine (CMM), of an existing part. A major problem in reverse engineering is that the measured points having an irregular format and unequal distribution are difficult to fit into a B-spline curve or surface. The paper presents a method for pre-processing data points for curve fitting in reverse engineering. The proposed method has been developed to process the measured data points before fitting into a B-spline form. The format of the new data points regenerated by the proposed method is suitable for the requirements for fitting into a smooth B-spline curve with a good shape. The entire procedure of this method involves filtering, curvature analysis, segmentation, regressing, and regenerating steps. The method is implemented and used for a practical application in reverse engineering. The result of the reconstruction proves the viability of the proposed method for integration with current commercial CAD systems.     

基于产品基因的概念设计

提出了一种基于特征的、通用的功能表达模型。通过对生物基因工程与产品原理方案设计的系统类比,引出产品原理方案设计中的信息遗传基础“产品基因”的概念,提出了“产品基因”的“转录”、“翻译”、“复制”以及“逆转录”机理,揭示了产品基因在功能设计与原理方案设计之间的桥梁作用。建立了基于产品基因遗传和重组的概念设计框架,并以一种新型硬币分离装置的原理方案设计为例进行验证。结果表明,该框架显然有助于产品概念设计阶段的原理创新。     

Design Change Model for Effective Scheduling Change Propagation Paths

Changes in requirements may result in the increasing of product development project cost and lead time,therefore,it is important to understand how requirement changes propagate in the design of complex product systems and be able to select best options to guide design.Currently,a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally.A new design change model is presented to systematically analyze and search change propagation paths.Firstly,a PDS-Behavior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains.Secondly,a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems,and the interaction relationships of the matrix elements are used to obtain an initial set of change paths.Finally,a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters.The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train’s bogie to show its feasibility and effectiveness.This model is not only supportive to response quickly to diversified market requirements,but also helpful to satisfy customer requirements and reduce product development lead time.The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency.     

基于RE的复杂曲面零件模具的快速设计与制造

随着现代计算机技术和测试技术的发展,利用逆向工程技术对产品进行建模、仿真、优化及新产品开发成为现代设计的一大热点,并已成为CAD/CAM领域特别是模具设计和制造的重要技术之一。以油壶切边模为例,采用逆向工程技术通过实物原型获取了油壶的三维轮廓数据,然后利用Pro/E等软件将得到的轮廓数据三维重构,得到了实物原型的三维数字模型,实现了油壶切边模具的设计与制造。采用逆向工程技术可以快速实现模具的设计与制造,大大缩短产品设计周期,提高产品竞争力。     

Modular design method based on simultaneous consideration of physical and functional relationships in the conceptual design stage

There are many benefits of a modular product including reduced cost, rapid product development and reduced production time. The modular design of products has been increasingly popularized in modern engineering design activity. A new design method is proposed to design a modular product based on relationships among functional requirements of the product to overcome the difficulty of modular design. Axiomatic design, the function-based design method and design structure matrix are efficiently combined in the proposed method. Functional requirements and design parameters are defined based on the independence Axiom of axiomatic design and the zigzagging process of axiomatic design is employed for the decomposition of functional requirements and design parameters. The function-based design method is utilized for the decomposition of functional requirements and the design structure matrix is used to modularize the design parameters of the bottom level of the zigzagging process. Three design examples are demonstrated to validate the proposed method. The results are discussed and the usefulness of the proposed method is presented.     

结合触觉交互的CAD反求建模与再设计

CAD反求建模是基于原型的先进设计方法,是实现创新设计的重要方法之一。触觉交互是人机交互领域的最新技术,可以实现传统CAD软件很难表达的不规则模型。介绍反求工程中的基于混合建模的CAD重构方法,并结合对鼠标进行再设计的例子,探讨如何在对产品进行CAD反求建模的基础上,利用触觉交互式设计系统FreeForm对其进行再设计,实现对原有产品的二次设计。     

基于逆向工程的汽车LED贴件门拉手设计

对基于逆行工程的汽车LED贴件门拉手设计进行了研究。介绍了运用逆向工程技术对现有汽车门拉手进行数字化模型重构,并在此基础上进行改进设计的方法、流程,并对工作要点进行了分析。     

基于Pro/Engineer车身外形的反求设计

随着RP行业的迅速发展,反求工程在快速成型制造领域中的作用日趋重要。它作为一种新的产品设计思想和方法越来越广泛地应用于汽车、模具等快速成型制造领域,并取得了很多成果。本文以Pro/Engineer为设计平台,利用跟踪草绘功能对产品模型进行外形重构,实现了东风标致307车模外形的反求设计。     

UG、Imageware在逆向工程三维模型重构中的应用研究

逆向工程技术是现代产品设计的一种重要手段,是消化和吸收先进技术的一种新方法,是先进制造技术的主力.三维CAD模型重构是逆向工程中的关键步骤.介绍了逆向工程的概念以及关键技术,全面分析了UG软件在逆向工程中的应用特点以及分析了利用UG进行曲面构造的方法和过程,总结了Imageware在数据点云处理优势以及进行数据处理的过程.利用学校现有的LSH-600型非接触式的三维激光扫描仪采集了汽车车身零件的几何数据,并详细介绍了数据采集的过程.最后结合Imageware和UG各自的优势,以汽车车身零件的三维模型的重构来讲述模型重构的过程.     

逆向工程技术应用研究

逆向工程是由已有产品回溯产品设计思路，通过研究现存的系统或产品，发现其规律，通过复制、改进、创新从而超越现有产品或系统的过程。逆向工程技术在产品设计中的应用可以缩短新产品设计开发周期，大大降低设计开发成本，提高设计水平和质量，有效地提高企业的市场竞争力。     

Research of design and analysis integrated information modeling framework for multibody mechanical system: with its application in the LHD design

Many complex mechanical products can be considered as multibody systems; 3D computer-aided design (CAD), multibody dynamics, finite element-based strength and fatigue analyses, optimization, and other CAE tools, are often used to develop this kind of product. But design is difficult and challenging because of information inconsistence among different engineering domains, and isolated information model islands exist. Lots of research are attracted to design and analysis information integration, but attentions are mainly focused on integration of CAD–finite element analysis (FEA), supporting the bottom-up design principle, while multibody dynamics analysis for analyzing global performance of a mechanical system is rarely considered, which follows the top-down design principle. In this paper, a novel multilevel system representation modeling framework for supporting both bottom-up and top-down or mixed design methods is proposed. It can integrate the product design CAD models with multibody dynamics, finite element-based strength and fatigue analyses, realizing a CAD–dynamic–FEA–fatigue analysis integration. It can also support data exchange and transfer in multidomain analyses. The framework is illustrated with a case study of a load haul dump (LHD) design using currently available software tools. Furthermore, a design case study of the working unit of the LHD is given to highlight the applicability of the modeling framework for multibody mechanical systems. It has been demonstrated that the framework can describe information exchanging and integration among CAD, FEA-based strength and fatigue analyses, and multibody dynamics analysis during a multibody mechanical product design process.