基于知識(shí)工程(kbe)設(shè)計(jì)方法外文文獻(xiàn)翻譯

1、<p><b>　　畢業(yè)設(shè)計(jì)</b></p><p><b>　　外文文獻(xiàn)翻譯</b></p><p><b>　　優(yōu) 集 學(xué) 院</b></p><p>　　外文資料名稱： Knowledge-Based Engineeri- </p><p>　　-ng

2、Design Methodology </p><p>　　外文資料出處： Int.J.Engng Ed.Vol.16.No.1 </p><p>　　附 件： 1.外文資料翻譯譯文 </p><p>　　2.外文原文 </p><p>　　基于知識(shí)

3、工程(KBE)設(shè)計(jì)方法</p><p>　　D. E. CALKINS</p><p><b>　　背景</b></p><p>　　復(fù)雜系統(tǒng)的發(fā)展需要很多工程和管理方面的知識(shí)、決策，它要滿足很多競(jìng)爭(zhēng)性的要求。設(shè)計(jì)被認(rèn)為是決定產(chǎn)品最終形態(tài)、成本、可靠性、市場(chǎng)接受程度的首要因素。高級(jí)別的工程設(shè)計(jì)和分析過(guò)程(概念設(shè)計(jì)階段)特別重要，因?yàn)榇蠖鄶?shù)的生命

4、周期成本和整體系統(tǒng)的質(zhì)量都在這個(gè)階段。產(chǎn)品成本的壓縮最可能發(fā)生在產(chǎn)品設(shè)計(jì)的最初階段。整個(gè)生命周期階段大約百分之七十的成本花費(fèi)在概念設(shè)計(jì)階段結(jié)束時(shí)，縮短設(shè)計(jì)周期的關(guān)鍵是縮短概念設(shè)計(jì)階段，這樣同時(shí)也減少了工程的重新設(shè)計(jì)工作量。</p><p>　　工程權(quán)衡過(guò)程中采用良好的估計(jì)和非正式的啟發(fā)進(jìn)行概念設(shè)計(jì)。傳統(tǒng)CAD工具對(duì)概念設(shè)計(jì)階段的支持非常有限。有必要，進(jìn)行涉及多個(gè)學(xué)科的交流合作來(lái)快速進(jìn)行設(shè)計(jì)分析(包括性能，成本，可

5、靠性等)。最后，必須能夠管理大量的特定領(lǐng)域的知識(shí)。解決方案是在概念設(shè)計(jì)階段包含進(jìn)更過(guò)資源，通過(guò)消除重新設(shè)計(jì)來(lái)縮短整個(gè)產(chǎn)品的時(shí)間。</p><p>　　所有這些因素都主張采取綜合設(shè)計(jì)工具和環(huán)境，以在早期的綜合設(shè)計(jì)階段提供幫助。這種集成設(shè)計(jì)工具能夠使由不同學(xué)科的工程師、設(shè)計(jì)者在面對(duì)復(fù)雜的需求和約束時(shí)能夠?qū)υO(shè)計(jì)意圖達(dá)成共識(shí)。那個(gè)設(shè)計(jì)工具可以讓設(shè)計(jì)團(tuán)隊(duì)研究在更高級(jí)別上的更多配置細(xì)節(jié)。問(wèn)題就是架構(gòu)一個(gè)設(shè)計(jì)工具，以滿足所有這

6、些要求。</p><p>　　虛擬(數(shù)字)原型模型</p><p>　　現(xiàn)在需要是一種代表產(chǎn)品設(shè)計(jì)為得到一將允許一產(chǎn)品的早發(fā)展和評(píng)價(jià)的真實(shí)事實(shí)上原型的過(guò)程的方式。虛擬樣機(jī)將取代傳統(tǒng)的物理樣機(jī)，并允許設(shè)計(jì)工程師，研究“假設(shè)”的情況，同時(shí)反復(fù)更新他們的設(shè)計(jì)。真正的虛擬原型，不僅代表形狀和形式，即幾何形狀，它也代表如重量，材料，性能和制造工藝的非幾何屬性。設(shè)計(jì)人員希望設(shè)計(jì)的表述，將成為一個(gè)既有幾

7、何又有非幾何屬性的物理原型確切的表示。</p><p>　　產(chǎn)品表示法已經(jīng)從二維的形狀和幾何的形式字形繪畫的表示法移動(dòng)向充分的三維幾何模型表示法。設(shè)計(jì)工具，用于設(shè)計(jì)工程領(lǐng)域的需要，顯然必須有剛才討論的所有工具的屬性。它必須結(jié)合計(jì)算機(jī)輔助設(shè)計(jì)系統(tǒng)的幾何表示法，能做對(duì)程序語(yǔ)言的工程分析和代表設(shè)計(jì)知識(shí)在一個(gè)專家系統(tǒng)。一個(gè)真正的虛擬原型包含此全方位設(shè)計(jì)知識(shí)。</p><p><b>　　

8、啟用的技術(shù)設(shè)計(jì) </b></p><p><b>　　知識(shí)類型</b></p><p>　　如同適用于KBE那樣，知識(shí)能分成四種類型：</p><p><b>　　.事實(shí)，</b></p><p><b>　　.程序，</b></p><p>

9、;<b>　　.判斷，</b></p><p><b>　　.控制。</b></p><p>　　在手冊(cè)找到的形式化的知識(shí)例如原材料明細(xì)表，設(shè)計(jì)data，ASTM標(biāo)準(zhǔn)和設(shè)備規(guī)格被認(rèn)為事實(shí)知識(shí)。算法的和操作的知識(shí)是程序上的知識(shí)的兩種形式。數(shù)字的和非數(shù)字的解決問(wèn)題一或者完成中的一些末端的過(guò)程是所有的算法的程序上的知識(shí)(APK)的原理。事實(shí)被APK通過(guò)

10、工程和分析算法改變。有效的程序知識(shí)(OPK)被用于創(chuàng)造，刪除和運(yùn)輸事實(shí)。OPK節(jié)目的例子是有限元素分析、優(yōu)化和數(shù)據(jù)庫(kù)管理系統(tǒng)[1]。經(jīng)驗(yàn)法則和共同的實(shí)踐是評(píng)斷知識(shí)的實(shí)例。啟發(fā)式，意見，經(jīng)驗(yàn)，與合情推理中還包括判斷的知識(shí)。邏輯和推理的形式原則是基本的判斷知識(shí)的應(yīng)用?？刂浦R(shí)元知識(shí)或知識(shí)有關(guān)知識(shí)，知識(shí)的其他類型的管理控制知識(shí)。仿造直系活動(dòng)，意想不到的發(fā)展的預(yù)期，并且應(yīng)付不確定性是所有特點(diǎn)控制知識(shí)[1]。</p><p&g

11、t;　　基于知識(shí)的工程(KBE)</p><p>　　該技術(shù)允許一個(gè)真正的產(chǎn)品虛擬樣機(jī)開發(fā)被稱為基于知識(shí)的工程，或KBE。KBE是捕捉和對(duì)結(jié)構(gòu)設(shè)計(jì)，其設(shè)計(jì)過(guò)程的知識(shí)方法。知識(shí)經(jīng)濟(jì)可以用來(lái)定義工程方法和程序[2]。在KBE，產(chǎn)品結(jié)構(gòu)樹(拓?fù)鋵W(xué))是動(dòng)態(tài)的，因此知識(shí)經(jīng)濟(jì)提供真正的工程自動(dòng)化，包括應(yīng)用開發(fā)，幾何造型，應(yīng)用程序部署和工具的集成。基于知識(shí)工程是一種編程工具，用于開發(fā)一個(gè)虛擬原型設(shè)計(jì)顧問(wèn)或?yàn)橐粋€(gè)建立了產(chǎn)品設(shè)計(jì)，

12、在給定的設(shè)計(jì)領(lǐng)域。</p><p>　　關(guān)于設(shè)計(jì)類的現(xiàn)有的知識(shí)在基于知識(shí)的工程學(xué)或設(shè)計(jì)被運(yùn)用(KBE或KBD)并且被組織入能用數(shù)據(jù)庫(kù)的格式由計(jì)算機(jī)。詳細(xì)設(shè)計(jì)或虛擬原型，然后迅速開發(fā)基于知識(shí)的工程(KBE)的設(shè)計(jì)方法，通過(guò)對(duì)23位計(jì)算能力來(lái)開發(fā)數(shù)據(jù)庫(kù)，和規(guī)則系統(tǒng)。該產(chǎn)品模型是在KBE環(huán)境下開發(fā)的虛擬樣機(jī)。虛擬原型，如材料的所有幾何特征或?qū)傩缘漠a(chǎn)品，以及非幾何屬性，質(zhì)量特性，應(yīng)力和撓度特性等虛擬樣機(jī)一旦被創(chuàng)建，它可以

13、由設(shè)計(jì)者使用評(píng)估成功或設(shè)計(jì)配置的優(yōu)點(diǎn)，然后修改。該產(chǎn)品模型表示后面的幾何設(shè)計(jì)工程意圖。在產(chǎn)品模型中包含的信息包括物理屬性如幾何，材料種類和功能限制。</p><p><b>　　生成技術(shù)</b></p><p>　　有三種KBE的工具，目前正在探索和發(fā)展類型。這些措施包括：</p><p>　　1．診斷方法(專家系統(tǒng))。</p>

14、<p>　　2．創(chuàng)造性的方法(設(shè)計(jì)顧問(wèn))/(設(shè)計(jì)檢查)。</p><p>　　3．生成方法(虛擬樣機(jī))。</p><p>　　專家系統(tǒng)是第一種類型的工具發(fā)達(dá)國(guó)家在工程領(lǐng)域的使用，這個(gè)工具用于診斷目的，例如分析汽車發(fā)動(dòng)機(jī)出現(xiàn)故障。</p><p>　　第二類，設(shè)計(jì)顧問(wèn)，更是目前的事態(tài)發(fā)展之一。它是用來(lái)反映了一個(gè)系統(tǒng)的設(shè)計(jì)過(guò)程，并告知約束和規(guī)則的基礎(chǔ)上違反設(shè)計(jì)

15、師與設(shè)計(jì)顧問(wèn)所載的規(guī)則。設(shè)計(jì)師在這意見后行動(dòng)并且做適當(dāng)?shù)淖儎?dòng)。</p><p>　　第三類涉及到建立一個(gè)以該模型中的規(guī)則為基礎(chǔ)的系統(tǒng)模型。這個(gè)模型，一個(gè)真正原型，然后起反應(yīng)對(duì)在屬性(幾何或非幾何)和再生原型的一個(gè)新的事例上的變化。 這是用于被開發(fā)的類KBE的種類。</p><p>　　KBE利用生成技術(shù)來(lái)獲取通用產(chǎn)品設(shè)計(jì)信息，包括幾何和拓?fù)浣Y(jié)構(gòu)，產(chǎn)品結(jié)構(gòu)的發(fā)展及制造工藝設(shè)計(jì)規(guī)則。生成建模地

16、圖功能規(guī)格，該產(chǎn)品的詳細(xì)陳述。一個(gè)生成模型的優(yōu)點(diǎn)是，由于產(chǎn)品需求的變化，外觀設(shè)計(jì)的表述是立即更新，直接影響到所有輸出。因此，KBE是一種動(dòng)態(tài)的對(duì)象模型，其中對(duì)外觀設(shè)計(jì)的表述是不斷更新。知識(shí)工程的方法設(shè)施為迅速生成模型生成新的功能規(guī)格設(shè)計(jì)的工程設(shè)計(jì)和制造知識(shí)獲取。相對(duì)于傳統(tǒng)的設(shè)計(jì)工具，KBE提供真正的設(shè)計(jì)與自動(dòng)化設(shè)計(jì)協(xié)助。在設(shè)計(jì)過(guò)程期間，KBE是系統(tǒng)的連續(xù)的再設(shè)計(jì)的一種健壯設(shè)計(jì)技術(shù)。 </p><p><b

17、>　　KBE的代表性產(chǎn)品</b></p><p>　　當(dāng)前KBE軟件是基于面向?qū)ο蠓窃V訟程序設(shè)計(jì)語(yǔ)言，比如LISP語(yǔ)言。因此，設(shè)計(jì)資料無(wú)須下令在模型正確，因?yàn)樗鼤?huì)制訂該命令本身。面向?qū)ο缶幊坦こ虒?duì)象的概念，用于表示的特點(diǎn)，無(wú)論幾何和非幾何，實(shí)際物理對(duì)象。對(duì)象不是被動(dòng)的，但可以反應(yīng)其他對(duì)象。一個(gè)對(duì)象可以創(chuàng)建和存儲(chǔ)信息和采取行動(dòng)應(yīng)對(duì)外部刺激。一個(gè)對(duì)象可以從另一個(gè)信息需求對(duì)象，或者將信息發(fā)送到另一個(gè)對(duì)

18、象。</p><p>　　KBE實(shí)現(xiàn)了真正的并行工程攻克了一系列的捐助領(lǐng)域的專門知識(shí)在一個(gè)組織。這可以包括代表從設(shè)計(jì)，工程，模具和其他制造業(yè)領(lǐng)域。KBE的供應(yīng)商有一個(gè)捕捉行之有效的方法和編纂這種產(chǎn)品信息的范圍。通常情況下，KBE的開發(fā)將與方法顧問(wèn)學(xué)習(xí)“知識(shí)捕獲”進(jìn)程的第一個(gè)發(fā)展項(xiàng)目，然后將轉(zhuǎn)讓和應(yīng)用這些技能后續(xù)項(xiàng)目。</p><p><b>　　KBE工具 </b>&

19、lt;/p><p>　　有許多不同的軟件工具可用于KBE發(fā)展。當(dāng)中包括ICADTM，TKSolverTM，設(shè)計(jì)LinkTM，ProEngineerTM，STONEruleTM和智能ElementsTM。所有這些集成了至少1 現(xiàn)代CAD系統(tǒng)提供一個(gè)當(dāng)代集成設(shè)計(jì)系統(tǒng)。 Unigraphics系統(tǒng)，CATIATM，支持EngineerTM，IDEASTM和自動(dòng)CADTM是一些選擇。這些軟件工具用于開發(fā)domainspeci

20、fic這兩個(gè)知識(shí)工程的方法設(shè)計(jì)工具，設(shè)計(jì)顧問(wèn)和虛擬樣機(jī)。</p><p>　　生成虛擬樣機(jī)(GVP公司)</p><p>　　這種虛擬原型的方法奠定了基礎(chǔ)的KBE描述，是基于對(duì)KBE的智能CAD軟件的使用[5]。智能CAD使用為元設(shè)計(jì)，這是設(shè)計(jì)工具設(shè)計(jì)在一個(gè)產(chǎn)品模型的形式。該產(chǎn)品模型是產(chǎn)品結(jié)構(gòu)，工程分析，產(chǎn)品成本，設(shè)計(jì)標(biāo)準(zhǔn)，管理準(zhǔn)則，材料特性，制造約束和進(jìn)程計(jì)劃的框架。它能夠輸出設(shè)計(jì)報(bào)告，

21、表示該產(chǎn)品的設(shè)計(jì)狀態(tài)。該報(bào)告可以包括例如：分析，3個(gè)數(shù)據(jù)的三維幾何模型，材料，成本報(bào)告和指示草案。GVP公司的捕獲和自動(dòng)化功能設(shè)計(jì)的規(guī)則和方法的理解在工程過(guò)程。在GVP公司為工程師提供了有效的替代功能選擇和操作。工程師添加他們的判斷力，優(yōu)化設(shè)計(jì)，最終系統(tǒng)。</p><p>　　阿生成虛擬樣機(jī)(GVP公司)是一個(gè)系統(tǒng)既是模型的幾何和非24 D.爾金斯等。一個(gè)產(chǎn)品(一個(gè)對(duì)象)的幾何屬性中嵌入了KBE的模式。它存儲(chǔ)知識(shí)

22、在組成一個(gè)產(chǎn)品模型系統(tǒng)設(shè)計(jì)和制造工程的規(guī)則，同時(shí)解決幾何和非幾何的問(wèn)題。阿生成虛擬原型是這些設(shè)計(jì)規(guī)則的組合，其中包括對(duì)工程指令用于創(chuàng)建的設(shè)計(jì)，也就是車輛的幾何形狀。生成虛擬樣機(jī)的代表背后的幾何設(shè)計(jì)工程意圖。它可以存儲(chǔ)諸如幾何和材料規(guī)格，以及過(guò)程和性能信息產(chǎn)品信息。</p><p>　　生成虛擬樣機(jī)的范例被定義如下：</p><p>　　生成：生成或自動(dòng)產(chǎn)生這一虛擬原型的實(shí)例，以響應(yīng)輸入狀態(tài)

23、向量。采取輸入規(guī)范說(shuō)明，運(yùn)用相關(guān)的做法并且自動(dòng)地引起設(shè)計(jì)。當(dāng)要求改變時(shí)，設(shè)計(jì)與所有表現(xiàn)產(chǎn)品一起立刻被更新。</p><p>　　虛擬的影響，雖然沒(méi)有實(shí)際的事實(shí)： [1]基于計(jì)算機(jī)模型</p><p>　　原型：原來(lái)的模式，或一個(gè)具體的例子類型。</p><p><b>　　設(shè)計(jì)規(guī)則</b></p><p>　　KBE是基

24、于知識(shí)的設(shè)計(jì)使用形式的設(shè)計(jì)規(guī)則，設(shè)計(jì)規(guī)則構(gòu)成了一個(gè)對(duì)象的核心。設(shè)計(jì)規(guī)則包括4種基本類型：</p><p>　　1.啟發(fā)式：包括實(shí)驗(yàn)的經(jīng)驗(yàn)規(guī)則和最佳做法。通常是基于企業(yè)文化設(shè)計(jì)的啟發(fā)。這些都是的類型，如果(條件為真)，然后(行動(dòng)推薦)。</p><p>　　2.經(jīng)驗(yàn)設(shè)計(jì)規(guī)則：這些規(guī)則根據(jù)從實(shí)驗(yàn)性數(shù)據(jù)被開發(fā)的曲線適合的表示。元模型技術(shù)用于開發(fā)復(fù)雜系統(tǒng)的模型。</p><p&

25、gt;　　3.立法限制：這些都是組成法律或工程的既定規(guī)則標(biāo)準(zhǔn)。</p><p>　　4.物理定律：首次原則為基礎(chǔ)的分析或數(shù)值模式的形式。也被稱為參數(shù)的規(guī)則。這些規(guī)則通常是使用報(bào)表模型解決簡(jiǎn)單的算法。</p><p>　　設(shè)計(jì)規(guī)則用于合成中的知識(shí)基礎(chǔ)知識(shí)，如何在給定的模型建立知識(shí)。設(shè)計(jì)規(guī)則來(lái)定義和涉及雙方在知識(shí)經(jīng)濟(jì)模式的屬性。工程師的方法和過(guò)程由這些規(guī)則仿造。設(shè)計(jì)規(guī)則類型包括：</p&

26、gt;<p><b>　　.計(jì)算</b></p><p><b>　　.條件句</b></p><p><b>　　.查尋數(shù)據(jù)庫(kù)</b></p><p><b>　　.固定</b></p><p><b>　　.變量</b&g

27、t;</p><p><b>　　.引用</b></p><p><b>　　.執(zhí)行外部程序</b></p><p><b>　　.選擇</b></p><p><b>　　.優(yōu)化。</b></p><p>　　Knowledge-

28、Based Engineering (KBE) Design Methodology</p><p>　　BACKGROUND</p><p>　　The development of complex systems requires a sequence of engineering and management decisions which must satisfy many com

29、peting requirements. Design is recognized as the primary contributor to the final product form, cost, reliability and market acceptance. The high-level engineering design and analysis process (conceptual design phase) is

30、 particularly important since the majority of the life-cycle costs and overall quality of the system are determined during this phase. The major opportunities</p><p>　　The engineering trade-off process durin

31、g conceptual design is undertaken using good estimations and informal heuristics. Current traditional CAD tool support is extremely limited for the conceptual design phase. There is need to rapidly conduct design analyse

32、s involving multiple disciplines communicating together (trading off such things as performance, cost, reliability, etc.). Finally, it is necessary to be able to manage a large amount of domain-specific knowledge. The so

33、lution is to commit m</p><p>　　All of these factors argue for an integrated design tool and environment that can help make decisions early in the design synthesis (conceptual design) process. This integrated

34、 design tool will enable a diverse and multi-disciplinary team of engineers, designers and stylists to achieve consensus of design intent under complex design requirements and increased design constraints. The design too

35、l should allow the design team to examine more configurations at greater levels of detail. The problem t</p><p>　　VIRTUAL (DIGITAL) PROTOTYPE MODEL</p><p>　　What is needed is a way to represent

36、the product design process to obtain a true virtual prototype which would allow the early development and evaluation of a product. The virtual prototype would replace traditional physical prototypes and allow the design

37、engineer to examine `what-if' scenarios while iteratively updating their designs. A true virtual prototype would not only represent the shape and form, i.e. the geometry, it would also represent non-geometric attribu

38、tes such as weight, materia</p><p>　　Product representation has moved from the 2-D orthographic drawing representation of the shape and form of the geometry, to full 3-D model representation of the geometry.

39、 The design tool that is needed for the design engineering domain, clearly must have attributes of all of the tools just discussed. It must combine the geometrical representation of the CAD systems, be able to do the eng

40、ineering analysis of the procedural languages and represent the design knowledge as in an expert system. A tru</p><p>　　ENABLING TECHNOLOGIES FOR DESIGN</p><p>　　Types of knowledge</p>&l

41、t;p>　　. Knowledge’, as applied to KBE, can be divided into four types [1]：</p><p><b>　　. facts,</b></p><p>　　. procedures,</p><p>　　. judgments,</p><p>　

42、　. control.</p><p>　　Formalized knowledge found in handbooks such as material specifications, engineering data，ASTM standards, and equipment specifications is considered factual knowledge. Algorithmic and op

43、erative knowledge are the two forms of procedural knowledge. Numeric and non-numeric procedures for solving a problem or accomplishing some end are all elements of algorithmic procedural knowledge (APK). Facts are transf

44、ormed by APK through engineering and analysis algorithms.Operative procedural knowledge (OPK) </p><p>　　Knowledge-based engineering (KBE)</p><p>　　The technology that allows the development of a

45、 true virtual prototype of a product is known as</p><p>　　knowledge-based engineering, or KBE. KBE is the methodology for capturing and structuring knowledge about a design and its design process. KBE may be

46、 used to define engineering methods and procedures [2]. In KBE, the product structure tree (topology) is dynamic, so that KBE offers true engineering automation including application development, geometric modeling, appl

47、ication deployment and tools integration. Knowledge-based engineering is a programming tool used to develop a virtual prototype or </p><p>　　Existing knowledge about a class of designs is utilized in knowled

48、ge-based engineering or design (KBE or KBD) and organized into a database format usable by computers. Detailed designs or virtual prototypes are then rapidly developed Knowledge-Based Engineering (KBE) Design Methodology

49、 23 through the use of digital computing power, developed databases, and systems of rules. The product model which is developed in the KBE environment is a virtual prototype. A virtual prototype has all of the geom</p

50、><p>　　Generative technology</p><p>　　There are three types of KBE tools that are currently being explored and developed. These include：</p><p>　　1. Diagnostic approach (expert system)

51、.</p><p>　　2. Creative approach (design advisor)/(design checking).</p><p>　　3. Generative approach (virtual prototype).</p><p>　　The expert system was the first type of tool develo

52、ped for use in the engineering domain.This tool is used for diagnostic purposes such as analyzing a malfunctioning automobile engine.</p><p>　　The second type,design advisor,is the one to more current develo

53、pments.It is used to follow the design process of a system, and advise the designer of constraint and rules violations based on rules contained with the design advisor. The designer then acts on this advice and makes app

54、ropriate changes.</p><p>　　The third type involves developing a model of the system based on rules contained with the model. This model, a virtual prototype, then reacts to changes in attributes (either geom

55、etric or non-geometric), and regenerating a new instance of the prototype. This is the type of KBE that is used in the classes developed.</p><p>　　KBE uses generative technology to capture generic product de

56、sign information, including geometry and topology, product structure development and manufacturing processes as design rules. Generative modeling maps functional specifications to a detailed representation of the product

57、. The advantage of a generative model is that as the product requirements change, the design representation is immediately updated directly affecting all outputs. Thus, KBE is a dynamic object model wherein the represent

58、</p><p>　　KBE product representation</p><p>　　Current KBE software is based on an object-oriented non-procedural design language such as LISP. As a result, the design information need not be ord

59、ered correctly within the model, as it will work out the order itself. Object-oriented programming works on the concept of objects that are used to represent the characteristics, both geometric and non-geometric, of actu

60、al physical objects. Objects are not passive, but can react with other objects. An object can create and store information and act i</p><p>　　KBE enables true concurrent engineering by capturing the domain e

61、xpertise of a range of contributors in an organization. This can include represent atives from design, engineering, tooling and other areas of manufacturing. KBE vendors have a well-established methodology for capturing

62、and codifying this range of product information. Often, KBE developers will collaborate with methodology consultants to learn the `knowledge capture' process on a first development project and then will transfer and&

63、lt;/p><p><b>　　KBE tools</b></p><p>　　There are a variety of software tools available for KBE tool development. Included are ICADTM, TKSolverTM, Design LinkTM, ProEngineerTM,STONEruleTM

64、 and Smart ElementsTM. All of these are integrated with at least one of the contemporary CAD systems to provide a contemporary integrated design system. Unigraphics,CATIATM, Pro-EngineerTM, IDEASTM and Auto-CADTM are som

65、e of the options.</p><p>　　These software tools are used to develop domain-specific design tools of the two KBE approaches,design advisor and the virtual prototype.</p><p>　　Generative virtual p

66、rototype (GVP)</p><p>　　The virtual prototype approach forms the basis of the KBE classes described, and is based on the use of the KBE software ICAD [5]. ICAD is used for metadesign, which is the design of

67、design tools in the form of a product model. The product model is the framework for the product structure, engineering analysis, product cost, design standards,regulatory codes, material characteristics, manu-facturing c

68、onstrains and process plans. It is able to output a design report that represents the design stat</p><p>　　A generative virtual prototype (GVP) is a system model that represents both the geometric and non-D.

69、 Calkins, et al.24 geometric attributes of a product (an object) which are embedded in the KBE model. It stores knowledge about a system in a product model composed of design and manufacturing engineering rules,which add

70、ress both geometric and nongeometric issues. A generative virtual prototype is a combination of these design rules and includes a set of engineering instructions used to create the</p><p>　　The generative vi

71、rtual prototype paradigm is defined as follows：</p><p>　　Generative： generate or automatically produce an instance of the virtual prototype in response to an input state vector. Take input specifications, ap

72、ply relevant procedures and generate a design auto-matically. When the requirements change, the design is updated immediately along with all of performance outputs.</p><p>　　Virtual： in effect although not i

73、n actual fact： a computer based model</p><p>　　Prototype： original model or example of a particular type.</p><p>　　Design rules</p><p>　　KBE is based on the use of design knowledge

74、in the form of ‘design rules’. The design rules form the kernel of an object. Design rules comprise four basic categories：</p><p>　　1. Heuristics： comprised of experimental rules of thumb and ‘best practices

75、’.Usually based on corporate culture design heuristics. These are of the type, If (condition is true), then (action recommended).</p><p>　　2. Empirical design rules： these rules are based on curve-fitted exp

76、ressions that are developed from experimental data. Meta-model technology used to develop models of complex systems.</p><p>　　3. Legislated constraints： these are comprised of rules established by law or by

77、engineering standards.</p><p>　　4. Laws of physics： based on first principles in the form of analytical or numerical models. Also known as parametric rules. These rules are usually simple algorithms that wou

78、ld be solved using spreadsheet models.</p><p>　　Design rules are used to synthesize the knowledge in the knowledge base and to establish how the knowledge is used in a given model. The design rules are used

79、to both define and relate the attributes in a KBE model. The methods and processes of an engineer are mimicked by these rules. Design rule types include：</p><p>　　. calculations</p><p>　　. condi

80、tionals</p><p>　　. look-up databases</p><p><b>　　. fixed</b></p><p>　　. variable</p><p>　　. references</p><p>　　. execute external programs<