工业设计英文论文

1、Computer-Aided Design 40 (2008) 812827 Reverse innovative design an integrated product design methodology XiuziYe a,b,. , Hongzheng Liu a, Lei Chena, Zhiyang Chenc, XiangPanc, Sanyuan Zhanga a Collegeof Computer Science/StateKeyLabof CAD&CG, Zhejiang University, 310027 Hangzhou,PR China bSolidWo

2、rks Corporation, 300 BakerAvenue, Concord,MA 01742, USAcCollegeof Software Engineering, Zhejiang UniversityofTechnology, 310014, Hangzhou,PR China Received24 August 2006; accepted7July 2007 Abstract Todaysproductdesignerisbeingaskedtodevelophighquality,innovativeproductsatanever increasingpace.Tomee

3、tthisneed,an intensive search is underway for advanced design methodologies that facilitate the acquisition of design knowledge and creative ideas for later reuse. Additionally, designers are embracing a wide range of 3D digital design applications, such as 3D digitization, 3D CAD and CAID, reverse

4、engineering(RE),CAEanalysisandrapid prototyping(RP).Inthispaper,we proposeareverse engineeringinnovativedesign methodologycalled Reverse Innovative Design (RID). The RID methodologyfacilitates design and knowledge reuse by leveraging 3D digital design applications. The core of our RID methodology is

5、 the definition and construction of feature-based parametric solid models from scanned data. The solid model is constructed with feature datato allow for design modification and iteration. Sucha constructionis well suited fordownstream analysis and rapid prototyping. In this paper, we will review th

6、e commercial availability and technological developments of some relevant 3D digital design applications.We will then introduce threeRE modelling strategies: an autosurfacingstrategy for organic shapes;a solid modelling strategy with feature recognition and surface fitting for analytical models; and

7、 a curve-based modelling strategy for accurate reverse modelling. Freeform shapes are appearing with more frequency in product development. Since their “natural” parameters are hard to define and extract, we propose constructionofafeatureskeleton based upon industrialorregional standardsorby user in

8、teraction. Globaland local product definition parameters are then linkedtothe featureskeleton. Design modificationis performedby solvingaconstrained optimization problem.ARID platformhas been developedandthe mainRE strategiesand core algorithmshave been integrated into SolidWorksasan add-in product

9、called ScanTo3D.We will use this system to demonstrate our RID methodology on a collection of innovative consumer product design examples. c. 2008 Elsevier Ltd. All rights reserved. Keywords:3D CAD; CAID; Reverse engineering; Product design methodology; Reverse innovativedesign; Feature-based modell

10、ing;Parametric modelling; Product definition parameters; Local shape deformation 1. Introduction Design is a purposeful process involving creative thinking and problem solving. Designandknowledgehaveavery strong association: recollection and application of knowledge can be considered as a straightfo

11、rward and practical design process 13. Emerging new techniques, devices and the globalization of the product market are pushing creativity to its limit. Todays market is characterized byfaster time-to-market, and greater demands for fresh and distinctive products. Facing intense market challenges, a

12、dvanced design methodologies are being actively sought to reduce the time required for . Corresponding author at: SolidWorks Corporation, 300 Baker Avenue, Concord,MA 01742, USA.Tel.:+1 978 371 5044;fax:+1 978 318 5259. E-mail addresses: yxz, xiuzi (X.Ye). knowledge acquisition in design activities,

13、 and to leverage creativity. It is estimated that designers spend about 60% of their time searching for information. This process is rated as the most frustrating aspect of an engineers design activities4. It is also conservatively estimated that more than 75% of engineering design activity comprise

14、s case-based design reuse of previous design knowledge to address a new design problem4.However,physical models and associated knowledge, which are increased considerably in complexity and quantity during the design process, are often not reused. This results in significant time and capital losses.

15、Hence, design and associated knowledge reuse is the key to reducing new product development costs. The use of 3D CAD (Computer Aided Design) tools is a prominent factor in shortening time-to-market and reducing c0010-4485/$ -see front matter . 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.ca

16、d.2007.07.006 X.Yeetal./Computer-Aided Design40 (2008) 812827 product development costs. With the wide adoption of 3D CAD technology5, product development has moved from physical to digital mockup, and from 2D to 3D design in the last few decades. 3D CAD has become part of a completely digital devel

17、opment process that includes design, modelling, simulation and tooling6,7.Asa result, more and more designs exist in 3D digital form and are maintained in product databases. For new designs, if a digital form of similar product model is readily available in the database, 3D searching techniques 4,8,

18、9 can be used to locate product models with similar shapes and design intent. In these cases, a new design can be accelerated by the reuse, in whole or part, of previous designs. 3D searching and reuse techniques have been extensively researched 10,11. Although there already are some commercially av

19、ailable 3D search engines12, 3D searching and reuse remains a very active topic of research in the design and media retrieval areas. On the other hand, with the rapid advancement of 3D data acquisition devices, Reverse Engineering (RE) technology has gained wide acceptance in the design community. T

20、his is especially true in the CAID (Computer Aided Industrial Design) community where physical models such as clay models are built and digitized. Unlike solid modelling CAD software packages which focus on making watertight solids, RE software packages typically output surface models. Many commerci

21、al 3D CAD software packages are feature based with parametric definitions of the features.A definition of a feature is given by the FEMEX (FEature Modeling EXperts)work group, see, e.g.13.A featureis defined as a representation of the shape aspects of a product that can be mapped to a generic shape

22、and functionally significant for some product life-cycle phase14. In practical terms, a feature can be viewed as the basic unit of product information that can represent a specific region. The term product can be a real, physical object or it can be a process. The term region describes a spatial or

23、geometrical portion of a physical object or a process-orientated portion of a process 15. In this paper, we use the term feature to represent design intent and design knowledge. High-level shape definition parameters such as radius, length, angles and width are presented to the designers, and constr

24、aints between geometrical entities such as dimension equality, parallelism, perpendicularity, co-linearity and concentricity are imposed. By changing these intuitive parameters and editing the constraints, different configurations canbe created for the same model, anda productfamily canbe obtained.

25、Usually, a feature tree is formed to record the history of the design process, and the feature creation sequence can be replayed. In RE software packages, however, surfaces (usually freeform surfaces) are created. While freeform surfaces have flexibility and allow the manipulations typically require

26、d in the conceptual design phase, theylacked the ability to express design intent or knowledge in a detailed and explicit manner. Although low-level shape parameters such as weights, knots, and control points 16 are available to adjust the freeform surfaces, they are counter-intuitive to designers.

27、Many shape deformation methods have been developed in the last decade to increase the intuitiveness of the freeform shape deformation, and to increase the designers ability to control the shape changes through mesh and surface deformation. This paper presents a new product design methodology called

28、Reverse Innovative Design (RID) which combines the benefits of these two worlds, namely the design intent and knowledge represented by features with their associated definition parameters; and the flexibility of shape deformation. Features with high-level definition parameters are directly created f

29、rom scanned data in a 3D CAD system. A new design can be obtained by changing these high-level definition parameters, while retaining aspects of the original design. Starting from a digitized model of an existing product or conceptual clay model, a clean mesh will be obtained by preprocessing of a p

30、oint cloud data (e.g. registration, sampling, noise data removal, global and local smoothing), meshing and mesh preprocessing (e.g. sampling, smoothing, topology repair and hole filling). From the cleaned mesh, a feature-based parametric solid model will be constructed with natural definition parame

31、ters by the extraction of analytically shaped features. For freeform product models, product definition parameters will be obtained based on the feature skeletons extracted from the mesh. The natural definition parameters of the features and the product definition parameters will be used for designo

32、f new products and productfamilies. Our RID provides three RE modelling strategies for different use case scenarios: (1) For organic shapes, C1 or C2 solid models are automatically generated from the mesh model. The solid model can be used in the application scenarios such as model references, data

33、transmission, high-quality graphics presentation and rapid prototyping. (2)Formore analyticalshapes,themeshmodelissegmented into functional regions called submeshes. Feature recognition techniques areexploitedtobuild analytically shaped featuresin a3D CAD package, resulting in high-level shape chara

34、cteristics (e.g. cylindrical, spherical, conical, extruded or revolved surfaces) and natural shape parameters (e.g. radius, length, height and angle). Submeshes that are not analytical are fitted by B-spline surfaces. All reconstructed surfaces will be extended, trimmed and sewn into a solid (if pos

35、sible) in the 3D CAD software. (3) Shoulda more accurate modelbe required,acurve-based modelling strategy can be adopted. 2D or 3D sketches can be generated by inferring from the mesh model, and curves such as section curves, boundary curves, and feature lines can be generated from the digitized mod

36、el. From these curves, lofted surfaces (with one or two directional curve nets)17can be generated directly within the 3D CAD package. Freeform product design has been the main focus of conventional RE. Since their “natural” parameters are hard to be defined and extracted, in our RID we propose deali

37、ng with freeform product models by extracting global and local product definition parameters that are defined by international, domestic or industrial de-facto standards; or by user-defined key parameters. Designers can produce new design variations by editing the product definition parameters. X.Ye

38、etal./Computer-Aided Design40 (2008) 812827 Feature skeletons are extracted from the scanned 3D model, and product definition parameters are first obtained from feature skeletons. The obtained high-level product definition parameters can then be adjusted which results in deformation of the feature s

39、keletons, and their corresponding submeshes, and hence the feature surfaces. Alternatively, local deformation of the feature skeletons can result in the deformation of the submeshes, and induce a deformation on the feature surfaces. These deformations are performed by solving a constrained minimizat

40、ion problem. Surfaces can also be deformed by using the deformation tools provided in the 3D CAD packages. In essence, RID can rapidly produce new designs with shape variations, from a scanned physical or clay model. The new designcanthenbe analysed geometrically,visuallyandbyCAE analysis packages.

41、Other evaluations such as manufacturability and cost can follow1821. Feedback from these analysis and evaluations will be used to modify the design through high-level product definition parameters or local shape deformation, and an iterative product design cycle is hence formed. RID is thus an integ

42、rated digital design methodology incorporating 3D digitizing, 3D CAD and CAID, RE, CAE analysis, and RP. RID also achieves seamless data integration among RE, CAID and CAD, and very tight data integration between CAD/CAID/RE, CAE analysis and RP. This paper is organized as follows: Section 2 gives a

43、n overview of related work, including recently developed modelling technologies such as image-based modelling, haptic modelling,3D data acquisition andRE technologies. Section 3 presents the overall workflow and detailed descriptions of the main processes of our RID methodology. Section 4 introduces

44、 three RE modelling strategies: (1) automatic surface modelling for organic shapes suitable for model references, graphics presentation and rapid prototyping. (2) feature-based RE solid modelling with mesh segmented into functional submeshes, and analytically shaped features and their natural parame

45、ters extracted. The remaining submeshes are fitted by B-spline surfaces. All the reconstructed surfaces will be extended, trimmed and sewn. (3) Curve based RE surface modelling with curves such as section curves and feature lines automatically extracted or manually constructed by sketching, and accu

46、rate surfaces generated using functionalities in 3D CAD software such as loft, sweep, extrude and revolve. Section 5 focuses on feature definition parameters for freeform shapes, and the extraction of feature skeleton and product definition parameters. Design variations through product definition pa

47、rameters and feature skeleton deformations are then discussed. Section 6deals with implementation aspect of our new design methodology. A RID platform has been developed and the main RE modeling strategies and core algorithms have been implemented and integrated into SolidWorks as an add-in product

48、called ScanTo3D. Innovative design examples are given in this section to demonstrate our new design methodology. Section 7 concludes the paper and gives discussions on future research directions. 2. Related work Design is first of all a process, a process of thought and planning. A variety of techni

49、ques have evolved to facilitate the manipulation and presentation of design ideas. With the rapid advances in computer technologies, the design paradigm is shifting. Digital design applications such as CAID/CAD, CAE analysis and RP are helping designers in conceptualizing, visualizing, prototyping a

50、nd delivering product models; and shortening the concept-to-market lead time. Although physical model making remains an important and integral part of industrial design, virtual 3D product modelling, simulation, RP and tooling have gained wide acceptance in product design practices. Among these, 3D

51、product modeling stands at the core of productdevelopment. Current commerciallyavailable digital design applications on the market can be seen from different perspectives as 3D CAD 2225 for forward and detailed design, CAID2628for conceptual and industrial design, and RE applications2931Notice that

52、some 3D CAD software packageshave embedded add-inRE packages2224. All state-of-the-art 3D CAD systems are built on a feature-based design paradigm. They have the following characteristics: 1. Feature based Each operation (add or remove) on the geometry will be recognized as a feature in a CAD system

53、. 2. Parametric Dimensional (include equation) and geometrical constraintsare parametersinafully definedCAD model. 3. History based All the parameters and features will be recorded on creation. Engineers can easily modify the parameters defined. 4. Designvariations and productfamily All the paramete

54、rs can be driven by the design variables. A product family can be quickly created in this way with models in different configurations. CAID, on the other hand, is used by industrial designers to define forms and appearances of the products. CAID has undergone rapid development and adoption in the la

55、st decade. As a visually creative activity, some of the CAID techniques allow spontaneous modelling, with others taking considerable timeandeffortto define surface details. Fig.1 showsa typical interface of CAID (Studiotools) and CAD (SolidWorks). Compared to 3D CAD software, CAID software has the f

56、ollowing characteristics: 1. Surface modeling 3D CAD software usually results in solids, and CAID surfaces. 2. Flexibility in deformation Shapes can be modified more freely in CAID using the embedded tools. In 3D CAD system, designer has more constraints such as precision. In consequence, it is hard

57、 to perform free shape deformation. 3. Material rendering Both CAD and CAID have rich material library, with CAD focused on engineering parameters for engineering computation and CAE analysis, and CAID focused on texture and colour appearance. 4. Flashygraphics In general, CAID system has a stronger graphical rendering engine for flashier graphical display and for presentations. X.Yeetal./Compute