芯子隔套（帶凸緣筒形件）沖壓成形工藝及模具設(shè)計(jì),芯子隔套（帶凸緣筒形件）沖壓成形工藝及模具設(shè)計(jì),芯子,凸緣,筒形件,沖壓,成形,工藝,模具設(shè)計(jì) * , Taiwan, of punch top Our use drawing dies for trunk lid outer panels and engine hood outer panels as concrete examples to showcase the power of our system. Experimental results show that our system can improve the design quality and reduce the design time and cost. expectation. Die design is part of the critical path of the entire development process. There are three categories of the die in design, which fundamentally reduced design time. However, most 3D CAD software only provides users with oped an expert system based on a configuration design method. This system allows users to design mechanical Solid Works using Visual C+. Chu, Song, and Luo (2006) developed a Computer aided parametric design sys- tem for 3D tire mold production in CATIA using CAA. In the stamping die design area, Cheok and Nee (1998) developed a knowledge based strip layout design system in AutoCAD. Taking advantage of neural network and CAD * Corresponding author. Tel.: +886 76 6011000; fax: +886 7 6011066. E-mail addresses: bt_linccms.nkfust.edu.tw (B.-T. Lin), u9314805 ccms.nkfust.edu.tw (S.-H. Hsu). Available online at Expert Systems with Applications stamping dies, based on their functionalities: drawing dies, trimming dies, and bending dies. Since most stamping dies for automotive sheet metals are big and complex, the stamping die design process is very time-consuming. Recently, as a result of the fast development of com- puter technology and of 3D CAD software, 3D CAD soft- ware has been widely used in designing drawing dies. A solid model oers users an intuitive and concrete view of products in a 3D environment. Roh and Lee (2006) pro- posed a hull structural modeling system for ship design, which was developed using C+ and built on top of 3D CAD software. Lee, Hsu, and Su (1999) developed a para- metric computer-aided die design system for cold forging using Auto-LISP. In order to make the modeling process more ecient, Kong et al. (2003) developed a Windows- native 3D plastic injection mold design system based on C211 2007 Elsevier Ltd. All rights reserved. Keywords: Drawing dies; Design system; CAD; Knowledge base; Parametric modeling 1. Introduction Press parts, such as frames, bodies, and doors, are widely used in the automotive industry. In order for a man- ufacturer to survive in todays competitive market, the development process of a vehicle needs to be carried out in an ecient and eective way in order to meet customers geometric modeling functions for constructing a solid model, but fails to oer a powerful design knowledge base, which is essential to assist engineers in accomplishing the design task. As a result, the developments of automated, knowledge base and intelligent design systems are studied by research- ers from around the world. Myung and Han (2001) devel- Automated design system Bor-Tsuen Lin Dept. of Mechanical and Automation Engineering, National Kaohsiung 824, Abstract This paper describes an automated design system for drawing dies. base, this system is able to output designs of the main components upon users input of design information of blank lines, die faces, hooks, guides, and stopper seats. This die design system is built on Part Design, Automation and Scripting, and Knowledge Advisor. 0957-4174/$ - see front matter C211 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.eswa.2007.01.024 for drawing dies Shih-Hsin Hsu Kaohsiung First University of Science and Technology, ROC Taking advantage of pre-built design knowledge base and data- a drawing die, such as upper dies, lower dies and blank holders, open lines, press data, and types of subcomponents such as of CATIA V5, and makes use of its built-in modules, including system also includes an inference engine, and user interfaces. We 34 (2008) 15861598 Expert Systems with Applications software, Pilani, Narasiman, Maiti, Singh, and Date (2004) proposed a method for automatically generating an optimal die face design based on die face formability parameters. Ismail, Chen, and Hon (1996) developed a fea- ture-based progressive press tool using cheap CAD soft- ware. Based on sheet metal operations, Singh and Sekhou (1999) developed a punch machine selection expert system, which was built in AutoCAD and used AutoLISP. Tisza (1995) developed an expert system for detail process plan- ning of metal forming in AutoCAD. Though the design process of drawing dies is extremely complex and requires a great deal of professional knowl- edge, the purpose of this paper is to develop an automated design system for drawing dies. Taking advantage of well- organized die design knowledge base and database and an integrated 3D CAD environment, our system is able to out- put designs of the main components of a drawing die, such as upper dies, lower dies and blank holders, upon users input of design information of blank lines, die faces, punch open lines (POL), press data, and types of subcomponents U-groove Triangle Rib Guide Stopper Seat Hook Auxiliary Plate Dieface Thickness Lower Die Size Hook Guide Cushion Pin Seat Stopper Seat Blank Holder Size Panel Guide Seat Avoid Structure Safety Area Avoid Structure B.-T. Lin, S.-H. Hsu / Expert Systems with Applications 34 (2008) 15861598 1587 U-groove Key-groove Auxiliary Plate Triangle Rib Lower Die Size Fig. 1. Structure of main components for a drawing die. Guide Safety Area Cushion Pin Hole Stopper Seat Hook Dieface Thickness (a) Upper die. (b) Blank holder. (c) Lower die. such as hooks, guides, and stopper seats. Experimental results show that our system can generate high quality design of main components of a drawing die in an ecient way. 2. Drawing die design 2.1. Drawing die configuration Drawing is a process of cold-forming a flat precut metal blankintoahollowvesselwithoutexcessivewrinkling,thin- ning, or fracturing (Wick, Benedict, 33 categories subcomponents with 42 dierent types are listed inoursystem.Theunderstandingoftherelationshipamong various subcomponents is vital to obtain an appropriate design process for each of the subcomponents. Detailed modeling processes for each subcomponent, as well as geo- metricoperationsusedinsuchprocesses,areavailableinthe knowledge base. Also, design guidelines and 3D diagrams with design parameters, itemized text, and formulas are stored as e-books for training, debugging, and reference purposes. 3.4. The design database The design database oers subcomponent specifications and press machine specifications. The subcomponent spec- ifications specify the sizes of each of the subcomponents, while the press machine specifications specify size of the bolster, maximum and minimum of the die height, maxi- mum die width, positions and sizes of T grooves and cush- ion pin holes, and cushion pin strokes. The design database has 44 types of subcomponent design specifications, which fall into 33 categories. The design specifications for each of the subcomponents are illustrated in 2D diagrams. In addition, each diagram is accompanied by a table that summarizes the related shape parameters and standard sizes. The design database oers four sets of press machine specifications, which are pre- sented in 2D diagrams. All information in the design data- base is stored as e-books for easy access. 3.5. CAD software Our system is developed based on CATIA V5 CAD soft- ware in the Windows XP operating system. This system is designed to be used in a PC, and is developed using the CATIA softwares built-in modules. The Part Design mod- ule is responsible for controlling and executing the process of constructing 3D models. Therefore, this module is used to build the inference coordinator. The Knowledge Advisor 1592 B.-T. Lin, S.-H. Hsu / Expert Systems with Applications 34 (2008) 15861598 Fig. 8. The layer tree of drawing die. module allows users to embed related knowledge into the design, which increases the productivity of design engi- neers. The subcomponent selector takes advantage of the Formula Editor and Rule Editor functions, while the shape calculator uses the Design Table function. The Automation and Scripting module oers a user-customized interface for CAD software. The model generator makes use of Visual Basic for Application (VBA) to develop programs for gen- erating solid models. The user interface also uses VBA to construct alphanumeric and graphic input interfaces. 4. Modeling process of the automated design system This system is built on top of the CATIA CAD system, and takes advantage of various CATIA built-in modules. Upon users input of the design information, our system Fig. 9. Sample die. B.-T. Lin, S.-H. Hsu / Expert Systems with Applications 34 (2008) 15861598 1593 Fig. 10. Program design. is able to automatically generate the solid model design of main components of a drawing die in an ecient and flexi- bleway.Fig.5showsthemodelingprocess.Eachstepofthe modeling process is detailed in the following sections. 1594 B.-T. Lin, S.-H. Hsu / Expert Systems with Applications 34 (2008) 15861598 Fig. 11. Interface for replace procedure of graphic data. (a) Load a graphic data. (b) Active replace window. (c) Ready for update. the design process, which makes programs more concise. Therefore, appropriate number of parameters is vital to the entire design process. All of the changeable dimensions are treated as parameters, whose values can be changed based on design requirements. Since the values of the dimension parameters cannot be non-positive, all possible situations should be taken into consideration to avoid any potential problems, especially when there are cause-and- eect relationships among the various subcomponents. 4.4. Parameter settings There are hundreds of parameters in our automatic design system, which demands a systematic naming schema so that parameters can be well managed to facilitate coding and debugging. The name of a parameter used in our sys- tem consists of two parts: the name of the part to which the parameter belongs, and the name of the dimension. Based on the parameters functionality, they can be divided into shape parameters and position parameters. Shape parameters can be further classified as dependent parameters and independent parameters. Independent with Applications 34 (2008) 15861598 1595 4.1. Die structure analysis Drawing dies for the automotive industry are very large, and have very complicated structures. Moreover, each sub- component has its own functionality. Therefore, before developing the design system, we collected various struc- tures of drawing dies for automotive sheet metals, and ana- lyzed their architectures and functions. Fig. 6 shows a classification of the subcomponents of a typical drawing die based on their functionality. The parameterized die design system treats the change- able dimensions of a die as parameters, and generates the final design by assigning appropriate values to each of the parameters based on design formulas, constraints and tables derived from the design guidelines and specifications. However, certain data and subcomponents, such as press machines, hooks, guides, and stopper seats, cannot be designed simply by changing the design parameters because of the diversity of their structures. Therefore, we pre-build the interfaces and structures of a sample die for all subcom- ponents that share the same functionality based on design guidelines and specifications. 4.2. Design process standardization The purpose of design process standardization is to pro- vide a systematic way of designing dies. Since the CAD sys- tem has its own modeling process, the size and position of design subcomponents cannot be determined until the size and position of certain subcomponents are fixed. A stan- dardized design process, as shown in Fig. 7, is generated based on the design guidelines and specifications of each of the subcomponents, as well as the cause-and-eect rela- tionships among these subcomponents. This standardized process is used to guide the design of main components of sample dies, such as their structures and initial sizes, as well as the initial sizes and positions of each subcompo- nent on a main component. 4.3. Sample die construction Once a standardized design process is obtained, a fea- ture layer tree and sample dies are developed based on the design process, as shown in Figs. 8 and 9. A typical die face consists of thousands of surfaces. In order to ensure the stability of a sample die, simple die faces are used to construct sample dies. Since various subcompo- nents of a drawing die can share a common functionality, all possible subcomponent structures of a function must be pre-constructed when constructing sample dies. When constructing a solid model of a die, only the selected sub- components should be activated. All unselected subcompo- nents should be deactivated. When constructing sample dies, design engineers should make use of all available parameters and pre-set sizes. The B.-T. Lin, S.-H. Hsu / Expert Systems numberofparametershasadirectimpactonthedesignflex- ibility.Inmostcases,thenumberofparametersdecreasesin Fig. 12. Alphanumeric data interface. parameters only need to meet the design guidelines, while dependent parameters are determined by both the design specifications and any relevant independent parameters. Taking the bolt type hook shown in Fig. 3 as an example, the diameter of the hook bolt, d, is an independent param- eter, while the other measures, such as Y, X, r, t, l, and R, are dependent parameters. 4.5. Programming Once the parameters have been identified, the relation- ships among various parameters need to be formulated based on design guidelines and specifications. These rela- tionships are further converted into programs. Programs are divided into three levels in order to facilitate the design process. Taking the bolt type hook as an example, the purpose of the first level is to select subcomponents based on design guidelines. This level of program takes advantage of two built-in modules of CATIA V5, Rule Editor and Formula Editor, to convert design guidelines into constraints and formulas respectively, which are used to determine the quantity, position and size of subcomponents, as shown in Fig. 10a and b. The second level of the program is responsible for calcu- lating the values of shape parameters of the die. This level takes advantage of the built-in modules of CATIA V5 to construct the design table of the die based on the design specifications of each subcomponent, so that this level of the program can use the design table and related indepen- dent to determine dependent parameters, as shown in Fig. 10c. The third level of the program is used to construct of the model. Written by VBA, this level of program is used to provide a modeling procedure of subcomponents based on determined the type and size of aforementioned two lev- els, as shown in Fig. 10d. 4.6. User interfaces User interfaces allow users to accomplish the design process in an intuitive and interactive way. The user inter- faces used in our system can be classified into two categories. 1596 B.-T. Lin, S.-H. Hsu / Expert Systems with Applications 34 (2008) 15861598 Fig. 13. Design process of the proposal system. (a) Sample die. (b) Graphic data outer panel. interface. (c) Alphanumeric data interface. (d) Drawing die for trunk lid ns with The first category is used to input graphic information, suchasblanklines,diefacesandPOLs.Thissetofinterfaces is using Replace, which is a built-in function of CATIA V5. Following are the procedures for replacing sample graphic information. First, start the automated design system, and Fig. 14. Compariso B.-T. Lin, S.-H. Hsu / Expert Systems load the desired graphic information into the design envi- ronment. Click on the layer tree representation of the sam- ple graphic information, as shown in Fig. 11a, and open theReplacewindow,asshowninFig.11b.Selectthedesired graphic information of the die and click OK. The color of the die turns to red when it is being updated, as shown in Fig. 11c. The second category is used to input alphanumeric information, such as types of press data, guide mechanism, and hooks and stopper seats, as shown in Fig. 12. Imple- mented using VBA, a drop-down menu allow users to select the appropriate types of subcomponents for the die. Design engineers only need to select the desired press machine and types of subcomponents, and click OK; the system is able to automatically complete the design. 5. Case study We use the design of drawing dies for a trunk lid outer panel as a concrete example to showcase the power of our system. A standard structure diagram of sample dies is dis- played when the system starts, as shown in Fig. 13a. Upon receiving graphic information from the user, our system uses CATIAs built-in Replace function to replace the gra- phic information using the layer tree of the sample die, as shown in Fig. 13b. Then, users begin to input alphanumeric information, such as the types of press machines, guide mechanism, hooks, and stopper seats, as shown in Fig. 13c. After users click OK, our system begins to gener- ate the design based on the design processes, guidelines and specifications. The final design of the drawing die is shown of die structures. Applications 34 (2008) 15861598 1597 in Fig. 13d. Fig. 14 presents a comparison of two dierent drawing dies, a drawing die for trunk lid outer panels and a drawing die for engine hood outer panels, to show that our system can handle a wide range of designs. 6. Conclusions and future works This paper presents an automated design system for drawing dies, which is built on top of CATIA CAD soft- ware. Upon receiving the initial design information from design engineers, such as blank lines, die faces, POLs, and press data, as well as the types of hooks, guide mech- anism, and stopper seats, the system is able to automati- cally generate the final design of main components of the die, such as upper dies, lower dies, and blank holders. Design formulas and geometric operations of modeling processes are generated by the system using the built-in modules of CATIA V5, such as Part Design, Automation and Scripting, and Knowledge Advisor. Experimental results show that our system has successfully reduced the design time from several working days to within one hour when designing a drawing die for trunk lid outer panels and engine hood outer panels, which saves a great deal of development time and cost and achieves high product quality and design flexibility. In the future, an optimization module can be introduced into our system, which will enable it to output an optimal design. Moreover, since our system can only handle draw- ing dies at this time, we would like to extend our system to be able to design trimming dies and bending dies. References Cheok, B. T., & Nee, A. Y. C. (1998). Trends and developments in the automation of design and manufacture of tools for metal stampings. Journal of Materials Processing Technology, 75, 240252. Chu, C. H., Song, M. C., & Luo, C. S. (2006). Computer aided parametric design for 3D tire mold production. Computers in Industry, 57, 1125. Ismail, H. S., Chen, S. T., & Hon, K. K. B. (1996). Feature-based design of progressive press tools. International Journal of Machine Tools and Manufacture, 36, 367378. Kong, L., Fuh, J. Y. H., Lee, K. S., Liu, X. L., Ling, L. S., Zhang, Y. F., et al. (2003). A windows-native 3D plastic injection mold design system. Journal of Materials Processing Technology, 139, 8189. Lee, R. S., Hsu, Q. C., & Su, S. L. (1999). Development of a parametric computer-aided die design system for cold forging. 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