油缸校直機(jī)設(shè)計(jì)【7張CAD圖紙和畢業(yè)論文打包】
油缸校直機(jī)設(shè)計(jì)【7張CAD圖紙和畢業(yè)論文打包】,7張CAD圖紙和畢業(yè)論文打包,油缸校直機(jī),設(shè)計(jì),cad,圖紙,以及,畢業(yè)論文,打包
附錄一 基于網(wǎng)絡(luò)的快速原型制造
摘要：這篇論文提出了新的基于快速原型快速產(chǎn)品開(kāi)發(fā)集成系統(tǒng),發(fā)展了通過(guò)充分利用迅速發(fā)展的計(jì)算機(jī)網(wǎng)絡(luò)和信息技術(shù)的網(wǎng)絡(luò)制造服務(wù)系統(tǒng),這個(gè)系統(tǒng)提供更好的在中小型企業(yè)中對(duì)于快速產(chǎn)品開(kāi)發(fā)的支持。提出了制造業(yè)的網(wǎng)絡(luò)化服務(wù)體系的架構(gòu)。此外,一些關(guān)鍵問(wèn)題,包括模型、規(guī)劃制造鏈,選擇可行的合作廠家,排列制造任務(wù),利用同步協(xié)作的工作環(huán)境,建立一個(gè)適合管理平臺(tái)等問(wèn)題得到了論述?？蛇\(yùn)行java的解決辦法與網(wǎng)絡(luò)技術(shù),用于建立這樣一個(gè)網(wǎng)絡(luò)服務(wù)系統(tǒng)。最后提供了一個(gè)這種服務(wù)的應(yīng)用系統(tǒng)的實(shí)例。
關(guān)鍵詞：快速原型制造、服務(wù)系統(tǒng)
1．簡(jiǎn)介
這是信息技術(shù)時(shí)代. 信息技術(shù)影響社會(huì)各領(lǐng)域,并且大大影響了傳統(tǒng)工業(yè)。現(xiàn)代企業(yè)正面臨新的挑戰(zhàn):快速反應(yīng)的商機(jī)——一直被視為以保證公司的競(jìng)爭(zhēng)力最重要的因素之一；制造業(yè)發(fā)展走向數(shù)字化、網(wǎng)絡(luò)和全球化.。為了有效的響應(yīng)變化，生產(chǎn)策略，根據(jù)市場(chǎng)情況和客戶需求在時(shí)時(shí)變化。任何改變策略,應(yīng)該使廠商更能自己有能力應(yīng)付這樣的需求,減少生產(chǎn)時(shí)間,提高質(zhì)量和速度,能夠?yàn)槿蚩蛻籼峁﹥?yōu)質(zhì)的產(chǎn)品，改善交通運(yùn)輸系統(tǒng)[1]。這是既定的事實(shí),在設(shè)計(jì)和制造中利用計(jì)算機(jī)為獲得很大的工業(yè)生產(chǎn)力的提供了最重要的機(jī)會(huì)。未來(lái)制造業(yè)組織將是信息化,知識(shí)驅(qū)動(dòng)和依據(jù)聯(lián)系到每個(gè)人的全球信息網(wǎng)絡(luò)自動(dòng)化的自動(dòng)控制，目前已被廣泛認(rèn)同。為了滿足產(chǎn)品快速發(fā)展的需求,各種新技術(shù),如逆向工程(RE)、快速Prototyping(RP),快速工具制造(RT)等出現(xiàn)了,并且被視為能夠縮短產(chǎn)品研制時(shí)間和制造是鍵的有利工具。例如,有人說(shuō)RP可以節(jié)省新產(chǎn)品開(kāi)發(fā)費(fèi)用到70%和市場(chǎng)時(shí)間的90%。但是,這些設(shè)備對(duì)中小型企業(yè)(SMEs) 都太貴,并且許多技術(shù)比如3D固體模型、RP規(guī)劃過(guò)程,自由形式表面重建等,都需要高技能人才來(lái)完成。因此,對(duì)中小企業(yè)在產(chǎn)品開(kāi)發(fā)過(guò)程充分利用這些技術(shù)是特別困難的。為了大量中小企業(yè)的產(chǎn)品快速制造得到發(fā)展提供支持, 許多RP事務(wù)局(SBS),不僅可以制造物理原型、快速原型工具，還提供其它的工程服務(wù),已建立起來(lái)。到2001年, 世界各地有500多個(gè)SBS。但并不是需要每個(gè)SB能處理所有的設(shè)計(jì)和制造能力,但必須有效運(yùn)用外部資源,以更好地滿足客戶的需求。即通常定義為一個(gè)臨時(shí)聯(lián)合企業(yè)的以計(jì)算機(jī)網(wǎng)絡(luò)支持的虛擬企業(yè)將被建立。他們是為了滿足商機(jī)一起分享他們的技能、核心能力和資源,。每個(gè)SB處理自己的核心任務(wù),并且需要大量的合作伙伴來(lái)完成其它這個(gè)SB不能按時(shí)完成的工作。強(qiáng)調(diào)服務(wù)質(zhì)量的新思路,變成一個(gè)制造業(yè)在21世紀(jì)贏得全球競(jìng)爭(zhēng)的基本方略。遠(yuǎn)距離服務(wù)是一個(gè)針對(duì)廠商和顧客“服務(wù)”問(wèn)題的新興領(lǐng)域。因?yàn)閿?shù)字制造業(yè)技術(shù)進(jìn)步很快,數(shù)字服務(wù)將沒(méi)有阻礙的進(jìn)入綜合數(shù)字系統(tǒng)設(shè)計(jì)和制造。結(jié)合計(jì)算機(jī)和多媒體的因特網(wǎng)，為商業(yè)和制造業(yè)的遠(yuǎn)程融合和協(xié)作提供了巨大的潛力。對(duì)于SBs和SMEs，完成網(wǎng)絡(luò)制造平臺(tái)，來(lái)加速生產(chǎn)效率是非常緊迫的。這篇論文的其他部分組織如下：1.在第二部分回憶了相關(guān)的研究工作2.在第3部分,我們介紹一個(gè)基于RP的完整的得到快速發(fā)展的系統(tǒng)。第四部分?jǐn)⑹鼍W(wǎng)絡(luò)制造服務(wù)體系的了流程及功能設(shè)計(jì)。第5部分介紹系統(tǒng)運(yùn)行平臺(tái)配置。第6部分我們討論了互聯(lián)網(wǎng)應(yīng)用設(shè)計(jì)。第7部分研究了案例。最后,第8部分是論文的總結(jié)。
2 、相關(guān)的研究
伴隨著計(jì)算機(jī)網(wǎng)絡(luò)和信息技術(shù)的發(fā)展,網(wǎng)絡(luò)制造技術(shù)在制造業(yè)中發(fā)揮著越來(lái)越重要的作用。近年在世界各地來(lái)自學(xué)術(shù)界和工業(yè)團(tuán)體為支持網(wǎng)絡(luò)制造的研究與實(shí)踐(或全球制造或者遠(yuǎn)程制造)作了大量投資。一些戰(zhàn)略和框架已經(jīng)提出。 Abdel-Malek等[8]描述了一個(gè)架構(gòu),讓公司可以把一些生產(chǎn)和設(shè)計(jì)活動(dòng),通過(guò)互聯(lián)網(wǎng)發(fā)展模式,以協(xié)助公司選擇可替代的技術(shù)和功能,最大限度地發(fā)揮靈活性。Montreuil等[9]提出了一個(gè)戰(zhàn)略框架,提出了設(shè)計(jì)和制造靈活的經(jīng)營(yíng)網(wǎng)絡(luò),以動(dòng)態(tài)掌握使合作計(jì)劃、控制和管理日常的環(huán)境。Tso等介紹了代理式的協(xié)作支持服務(wù)系統(tǒng), 通過(guò)專(zhuān)門(mén)設(shè)計(jì)一些虛擬代理信息網(wǎng)絡(luò)，能夠滿足制造服務(wù)的要求。Chen等[11]提出了基于網(wǎng)絡(luò)設(shè)計(jì)與制造的綜合框架,是基于java和CORBA技術(shù)的。Offodile和Abdel-Malek 利用虛擬制造模式將制造業(yè)和信心產(chǎn)業(yè)融合的戰(zhàn)略框架。Huang等提出了對(duì)于虛擬企業(yè)架構(gòu)和控制機(jī)制的框架。O’Sullivan[14]描述了信息結(jié)構(gòu)及相關(guān)資料,來(lái)了解和處理商業(yè)發(fā)展。Akkermansa和HORSTC[15]討論了信息技術(shù)基本標(biāo)準(zhǔn)化公司的管理方并指出了戰(zhàn)略框架以指導(dǎo)管理者基于一些原有的經(jīng)濟(jì)與管理理論作出明智的決定,如交易費(fèi)用理論、組織設(shè)計(jì)和成熟發(fā)展階段。Jin等[16]提出研究和關(guān)鍵技術(shù)的應(yīng)用解決方案,其中包括確保網(wǎng)絡(luò)數(shù)據(jù)在成員之間傳輸?shù)陌踩呗裕换赪eb/Dotd的數(shù)據(jù)管理(分布對(duì)象技術(shù))、XML標(biāo)準(zhǔn)，能夠保證不同結(jié)構(gòu)環(huán)境的數(shù)據(jù)交換；提供各類(lèi)服務(wù)轉(zhuǎn)換文件的網(wǎng)絡(luò)平臺(tái)。 Woerner和Woern網(wǎng)絡(luò)服務(wù)提出了新的發(fā)展平臺(tái)，提供了虛擬工程合作生產(chǎn)的方法。
為了充分認(rèn)識(shí)當(dāng)今全球化的制造業(yè)的遠(yuǎn)程工程及當(dāng)前市場(chǎng)形勢(shì)和客戶需求,一些全球生產(chǎn)網(wǎng)絡(luò)已經(jīng)建立,其中包括在社會(huì)生產(chǎn)工程師、LockheedMartin(AIMSNET)[19]、3M(3M創(chuàng)新全球網(wǎng)絡(luò))。
今天的產(chǎn)業(yè)正面臨嚴(yán)重的其快速發(fā)展所帶來(lái)的全球海外活動(dòng)集成制造環(huán)境的結(jié)構(gòu)性問(wèn)題,。服務(wù)和維修對(duì)于公司保持制造業(yè)生產(chǎn)力及國(guó)外地區(qū)客戶滿意變得極為重要。由于傳統(tǒng)服務(wù)臺(tái)的固有問(wèn)題,一些公司已開(kāi)始發(fā)展網(wǎng)上在線客戶服務(wù)支撐體系。Foo等綜合描述客戶服務(wù)臺(tái)對(duì)于互聯(lián)網(wǎng)服務(wù)的支持。Lee討論了遠(yuǎn)程服務(wù)系統(tǒng)設(shè)計(jì)制造設(shè)備和產(chǎn)品支持的概念框架和生命周期。已建立的示范遠(yuǎn)程客戶支持系統(tǒng)FCSA證明了Glober的項(xiàng)目。以上這些體系的目的是為有效滿足客戶在使用遠(yuǎn)程支持、維修設(shè)備。
加州大學(xué)研究和發(fā)展項(xiàng)目,稱(chēng)為遠(yuǎn)程制造廠(TMF)是建立在因特網(wǎng)上的自動(dòng)快速生產(chǎn)。 用戶可以使用TMF提供就業(yè)機(jī)會(huì),并維持系統(tǒng)自動(dòng)排隊(duì)。同時(shí)可以自動(dòng)檢查StL的許多缺陷。在設(shè)計(jì)和制造過(guò)程中使用RP技術(shù)可能帶來(lái)巨大的好處。但是,需要有效地利用這些好處,這些好處才能得到完全的開(kāi)發(fā)。對(duì)全球RP技術(shù)有一個(gè)了解是非常困難的。因?yàn)楹芸斐霈F(xiàn)了一些新的改進(jìn)方面的工作。為了幫助選擇合適的快速制造過(guò)程, 已經(jīng)開(kāi)發(fā)了許多快速原型系統(tǒng)選擇工作。Quickparts.com,這是一個(gè)私人擁有制造服務(wù)公司致力于提供客戶網(wǎng)上電子商務(wù)系統(tǒng)用于采購(gòu)量低、高生產(chǎn)量關(guān)稅地區(qū),并形成了一種系統(tǒng)QuickQuote。QuickQuote讓顧客得到為生產(chǎn)部件的快速的報(bào)價(jià)。3D系統(tǒng)公司是最早、最大的RP制造商,提供了通過(guò)互聯(lián)網(wǎng)的服務(wù)。
從這些調(diào)查的文字,顯然大部份的研究主要集中在戰(zhàn)略和總體結(jié)構(gòu)網(wǎng)絡(luò)制造以及個(gè)別功能模塊,還沒(méi)有一次全面comprebanausic網(wǎng)絡(luò)制造和服務(wù)體系,支持快速的產(chǎn)品開(kāi)發(fā)。 基于我們以前的工作,及新的研究,以網(wǎng)絡(luò)為基礎(chǔ)的生產(chǎn)服務(wù)體系的產(chǎn)品迅速開(kāi)發(fā)將被建立。
3 、快速制造的綜合系統(tǒng)結(jié)構(gòu)
從最初的概念設(shè)計(jì)到產(chǎn)品的商業(yè)性的發(fā)展過(guò)程包括:產(chǎn)品設(shè)計(jì); 性能分析，安全性和可靠性; 對(duì)產(chǎn)品原型試驗(yàn)評(píng)價(jià); 設(shè)計(jì)和修改。因此,新產(chǎn)品開(kāi)發(fā)的每一步進(jìn)程對(duì)產(chǎn)品市場(chǎng)化時(shí)間產(chǎn)生直接影響。一個(gè)好的產(chǎn)品開(kāi)發(fā)體系,使設(shè)計(jì)師或設(shè)計(jì)小組必須考慮各方面的產(chǎn)品設(shè)計(jì)、制造、銷(xiāo)售、回收初期的設(shè)計(jì)周期。因此,設(shè)計(jì)制作可輕易改變并有效。反饋越流暢,該系統(tǒng)成功的可能性越高。設(shè)計(jì)制造(DFM)和并行工程(CE)要求產(chǎn)品設(shè)計(jì)和開(kāi)發(fā)過(guò)程,同時(shí)得到發(fā)展，而不是按順序。
產(chǎn)品快速發(fā)展的綜合系統(tǒng)由三個(gè)單元組成:數(shù)字原型、物理原型和快速制造裝備與系統(tǒng)功能系統(tǒng)。產(chǎn)品開(kāi)發(fā)利用3維CAD軟件制造3D立體模型開(kāi)始。在這一階段,產(chǎn)品幾何形狀得到定義，它在美學(xué)上，尺寸上是多種多樣的。數(shù)字原型的主要功能是完成3D模型。在設(shè)計(jì)創(chuàng)作過(guò)程，產(chǎn)品及其部件在3D CAD系統(tǒng)上直接設(shè)計(jì)(如Pro/E、Unigraphics、CATIA、IDEA等)。 如果實(shí)體零件可用, 模型可用逆向工程技術(shù)建造的 (RE)。RE一種利用現(xiàn)有零件建立物理模型的方法,建立數(shù)字模型,然后用它來(lái)制造部件。如果為提高產(chǎn)品的性能而再設(shè)計(jì),RE能減少開(kāi)發(fā)周期。當(dāng)設(shè)計(jì)師采用模擬創(chuàng)造了一個(gè)新的設(shè)計(jì),還要進(jìn)一步利用數(shù)據(jù)分析和設(shè)計(jì)制造制造模擬模型。逆向工程的三個(gè)主要步驟是數(shù)字化特征提取、特征擴(kuò)展、3維 CAD模型。完成零件數(shù)字化的儀器可以是接觸和非接觸式。有各種商業(yè)化的數(shù)字化儀。從測(cè)量系統(tǒng),協(xié)調(diào)機(jī)(CMM)、激光掃描機(jī),到超聲波儀。它們可分為兩大類(lèi):接觸和非接觸式。激光掃描三角(LTS)、磁共振影像(MRI)、計(jì)算機(jī)斷層(CT)是常用的非接觸式的裝置。接觸式的主要有CMM和截面圖象測(cè)量(CIM)。特征提取通常是通過(guò)數(shù)據(jù)捕捉和捕捉表面特征。零件模型是通過(guò)填充適當(dāng)?shù)臄?shù)據(jù)面完成的。為了減少重復(fù)設(shè)計(jì)原型試驗(yàn)周期、提高生產(chǎn)過(guò)程,并增加機(jī)器的可靠性,必須通過(guò)CAE指導(dǎo)生產(chǎn),優(yōu)化設(shè)計(jì)和制造過(guò)程。
CAD模型可以利用RP直接轉(zhuǎn)化為實(shí)際的原型。RP是一個(gè)新的成型零件制造過(guò)程,是通計(jì)算機(jī)控制一層層的堆積，是直接從3D模型在很短的時(shí)間內(nèi)完成的。與傳統(tǒng)加工方法相反,多數(shù)的快速原型制造系統(tǒng)基于堆積過(guò)程,而非材料切除。 因此,這種方法不受規(guī)機(jī)械加工限制因素的限制常。在設(shè)計(jì)和制造過(guò)程中使用RP可能帶來(lái)巨大的好處。可以縮短產(chǎn)品市場(chǎng)化時(shí)間、降低成本和提高質(zhì)量。過(guò)去10年來(lái),已廣泛應(yīng)用于工業(yè)領(lǐng)域。主要的商業(yè)化RP技術(shù)包括業(yè)stereolithgraphy(ST)selectivelasersintering(SLS),融合沉積制造(FDM)、膠合物體制造(LOM)、彈道微粒制造(BMP)、三維印刷(3D印刷)等。
RT是一種技術(shù),把RP零件轉(zhuǎn)化為功能部件,特別是金屬零件。此外, RP、RT的融合推動(dòng)了公司并行工程的發(fā)展。許多由RP系統(tǒng)制造模具的生產(chǎn)過(guò)程得到發(fā)展。RT的方法大致可分為直接和間接的,軟、硬切削的。間接RT需要掌握某種模式,這種模式可以由常規(guī)方法(HSM等)獲得,或者由RP，SL，SLS獲得。直接RT,顧名思義,是直接由RP系統(tǒng)制造的,從而消除了中間產(chǎn)生步驟格局。根據(jù)上述技術(shù)、新產(chǎn)品開(kāi)發(fā)的綜合系統(tǒng)將迅速建立起來(lái)。詳細(xì)結(jié)構(gòu)如圖1。
4、 工作流程和功能設(shè)計(jì)
工作流程的生產(chǎn)服務(wù)體系網(wǎng)絡(luò)如圖2。 第一步是登陸SB網(wǎng)站。用戶用自己的名稱(chēng)和密碼進(jìn)入。那些沒(méi)有登記或核準(zhǔn)可以進(jìn)入系統(tǒng)的,只限于觀看資料,例如這一系統(tǒng)公開(kāi)的'典型案例'。進(jìn)入用戶的密碼將有系統(tǒng)驗(yàn)證。進(jìn)入網(wǎng)站成功之后,系統(tǒng)會(huì)自動(dòng)核對(duì)使用者的安全程度,確定哪些模塊可以進(jìn)入或使用。根據(jù)認(rèn)證的制度,所有用戶可分為四類(lèi):一般用戶(未注冊(cè))、潛在客戶,真正的客戶,系統(tǒng)管理員。接受客戶要求后,SB將首先進(jìn)行規(guī)劃過(guò)程的任務(wù)分解落實(shí),并選擇最合適的加工方法。在上未做后續(xù)工作之前，用戶必須得到產(chǎn)品的排隊(duì)和初步生產(chǎn)時(shí)間。 如果可以接受這樣的結(jié)果,在最初階段,SB進(jìn)一步與用戶進(jìn)行了電視會(huì)議。當(dāng)對(duì)方確認(rèn)合同,用戶成為真正的客戶。用戶提出的生產(chǎn)任務(wù)將由SB做到最好的實(shí)施。但是,如果SB沒(méi)有這樣的制造能力,或不能按時(shí)完成, 充分利用外部資源來(lái)源進(jìn)行未完成的任務(wù)，是一個(gè)有效的方法。下一步就是選擇合適的合作廠商,形成虛擬企業(yè)依靠分配制度完成任務(wù)的工作。此外,為了監(jiān)測(cè)安排,以確保生產(chǎn)的順利生產(chǎn),用戶與合作生產(chǎn)企業(yè),必須盡快實(shí)現(xiàn)基本信息、生產(chǎn)進(jìn)度時(shí)間表的生產(chǎn)監(jiān)管。所以落后或不符合質(zhì)量標(biāo)準(zhǔn)任何公司,將受到嚴(yán)格審查,及時(shí)采取預(yù)防和補(bǔ)救措施,提前預(yù)測(cè)損害。
提到上述流程網(wǎng)絡(luò)化服務(wù)體系和數(shù)字遠(yuǎn)程服務(wù)體系功能要求，服務(wù)體系包括九個(gè)功能模塊:技術(shù)研究、典型案例、信息咨詢(xún)、協(xié)議(應(yīng)用服務(wù)提供者)一套工具,客戶管理、電子商務(wù)、制造服務(wù)、導(dǎo)航系統(tǒng)。 詳細(xì)結(jié)構(gòu)見(jiàn)圖3。
這九個(gè)部分無(wú)阻礙的共同努力實(shí)現(xiàn)共同目標(biāo),即以提供及時(shí)有效的服務(wù)和產(chǎn)品平臺(tái),以支持中小企業(yè)發(fā)展迅速。其中一個(gè)目的是研究技術(shù),使用戶能更加了解相關(guān)的知識(shí)產(chǎn)品的快速發(fā)展。為了幫助讀者更好地了解和運(yùn)用這些新技術(shù)，系統(tǒng)說(shuō)明一些真實(shí)案例。技術(shù)研究和典型案例的主要提供自助服務(wù)的用戶。根據(jù)專(zhuān)家支配,SB能回答客戶的問(wèn)題并且有與用戶溝通解決問(wèn)題的信息咨詢(xún)模塊。
ASP了五項(xiàng)有用成分組成如下: RE/RP/RT的進(jìn)程規(guī)劃,STL檢查和維護(hù),零件優(yōu)化控制, 生產(chǎn)結(jié)構(gòu)支撐、零件優(yōu)化計(jì)算。逆向工程方法有多種,除了以前描述的RP和RT,每種都有其特點(diǎn)和適用范圍。按個(gè)別情況和任務(wù)的要求，選擇最合適的加工方法時(shí)非常困難的。根據(jù)ASP模式有3種選擇器,即“RE selector”、“RP selector”、“RT selector”。 StL固體模型之建立,減少約10%的時(shí)間。這表明自動(dòng)檢查錯(cuò)誤所有其它重要的業(yè)務(wù)對(duì)于RP控制室非常重要的。根據(jù)我們提供網(wǎng)絡(luò)資源的經(jīng)驗(yàn),我們知道, 在沒(méi)有設(shè)計(jì)者的網(wǎng)站進(jìn)行錯(cuò)誤自動(dòng)檢查時(shí)是特別重要的。在某些情況下我們已經(jīng)制定了各種算法發(fā)現(xiàn)自動(dòng)拓?fù)渑c幾何修補(bǔ)缺陷。有兩個(gè)'防火墻'發(fā)現(xiàn)這些缺陷:一是結(jié)合用戶操作。另外就是服務(wù)器后臺(tái)的管理。由于功能定位比較狹窄, StL如果有有致命缺陷或者移交期間失去部分檔案資料,就必須再?gòu)目蛻暨x擇材料。組成部分在制造過(guò)程中的質(zhì)量策劃可以用的方法有很大的不同。
5 結(jié)論和未來(lái)研究
為了滿足目前對(duì)快速產(chǎn)品開(kāi)發(fā)集成系統(tǒng)的需求, 提出了一種新的基于快速原型快速制造融合系統(tǒng), ,提出了更好的適合中小型企業(yè)的產(chǎn)品快速發(fā)展的網(wǎng)絡(luò)服務(wù)系統(tǒng)。一種方法是用JAVA制造網(wǎng)絡(luò)化服務(wù)體系建設(shè)的基礎(chǔ)上建造三層瀏覽器/服務(wù)器模式。自java引入這項(xiàng)技術(shù),可以很容易擴(kuò)展到基礎(chǔ)設(shè)施標(biāo)準(zhǔn)。服務(wù)體系包括技術(shù)信息平臺(tái)、電子商務(wù)平臺(tái)、制造服務(wù)平臺(tái),提供了生產(chǎn)協(xié)作環(huán)境和用戶服務(wù)局,使得部分制造資源有效地幫助中小型企業(yè)產(chǎn)品快速發(fā)展。
附錄二 A web-based manufacturing service system
for rapid product development
Hongbo Lana, Yucheng Dinga,*, Jun Honga, Hailiang Huangb, Bingheng Lua
Abstract
This paper proposes a novel integrated system of rapid product development based on rapid prototyping, and develops anetworked manufacturing service system which offers better support for the rapid product development in small and mediumsized enterprises by taking full advantage of the quickly evolving computer network and information technologies. The architecture of the networked manufacturing service system is presented. Furthermore, some of the key issues, includingmodelling and planning a manufacturing chain, selecting feasible collaborative manufacturers, queuing a manufacturing task, using the synchronously collaborative work environment, and constructing a suitable running platform, are described in detail. Java-enabled solution, together with web techniques, is employed for building such a networked service system. Finally, an actual example is provided illustrating the application of this service system.
Keywords:
Rapid product development; Rapid prototyping; Service system; Web-based application
1. Introduction
This is the era of information technology. Informationtechnology has influenced every realm of society, and dramatically impacted on the traditional industry.Current industries are facing the new challenges:quick response to business opportunity has been consideredas one of the most important factors to ensurecompany competitiveness; manufacturing industry isevolving toward digitalization, network and globalization.In order to respond to the change effectively,manufacturing strategy has to be modified from timeto time in accordance with the market situation andcustomer demand. Any change of strategy should enable manufacturers to be better equipped themselves,with capabilities to cope with demands suchas a faster response to market changes, a shortenedlead time of production, improved quality and speed,the ability to deliver quality products to global customers,and improved communications and transportationsystem [1]. It is an established fact that the useof computers in design and manufacturing constitutesthe most significant opportunity for substantial productivitygain in industry. It has now been widelyaccepted that the future of manufacturing organizationswill be information-oriented, knowledge drivenand much of their daily operations will be automatedaround the global information network that connectseveryone together [2]. In order to meet the demand ofrapid product development, various new technologiessuch as reverse engineering (RE), rapid prototyping (RP), and rapid tooling (RT) have emerged and areregarded as enabling tools with abilities to shorten theproduct development and manufacturing time. Forexample, it has been claimed that RP can cut newproduct development costs by up to 70% and the timeto market by 90% [3]. However, these equipments aretoo expensive for the small and medium sized enterprises(SMEs), and many techniques such as 3D CADsolid modelling, RP process planning, free-form surfacesreconstruction, etc., require the high skilled personnelto complete. Therefore, it is especially difficultfor the SMEs to take full advantage of these technologiesin the product development process. In order tooffer the support of rapid product development fornumerousSMEs,manyRPservice bureaus (SBs)whichcan not only manufacture physical prototype and rapidtooling but also provide other engineering services,have been established. By 2001, there are more than500 SBs all over the world. But not every SB canpossess all design and manufacturing capabilitiesrequired, it must employ effectively the externalresource to better satisfy client requirements. Namely,a virtual enterprise which usually defined as a temporaryalliance of enterprises that come together to sharetheir skills, core competencies, and resource in order tobetter respond to business opportunities, whose cooperationis supported by computer networks [4–6], is tobe founded. Every SBconducts only the tasks of its corecompetencies, and depends on numerous partners tocarry out the remaining tasks that this SB has no such manufacturing capabilities to accomplish in time.While a new thought emphasizing service quality is becoming a basic strategy by which manufacturing industries can win global competition in the 21st century. Teleservice engineering is an emerging fieldwhichaddresses ‘‘service’’ issue for manufacturers and customers. As digital manufacturing technique progresses quickly, digital service will be integrated seamlessly into the digital design and manufacturing system [7]. The internet, incorporating computers and multimedia, has provided tremendous potential for remote integration and collaboration in business and manufacturing applications. In order to provide a production collaborative environment for many SMEs and SBs to implement the networked manufacturing, it is especially urgent for many SBs and SMEs to construct a service platform of networked manufacturing to speed up the product development process of the SMEs.
The rest of this paper is organized as follows.Related research work is reviewed in Section 2. In Section 3, we introduce an integrated system of rapid product development based on RP. Section 4 describes the workflow and functional design of the networked manufacturing service system. The configuration of system running platform is presented in Section 5. In Section 6, we discuss the design of internet application. A case study is demonstrated in Section 7. Finally, Section 8 concludes the paper.
2. Related research
With the development of computer network and information technologies, the networked manufacturing techniques are playing a more and more important role in manufacturing industry. Substantial investments have been made to support the research and practice of networked manufacturing (telemanufacturing or global manufacturing) from both the academic community and industrial bodies all over the world in recent years. A number of strategies and frameworks have been proposed. Abdel-Malek et al. [8] described a structure within which a company can outsource several of its production and design activities via internet and developed a model to aid a company in selecting among the available technological and functional alternatives to maximize its flexibility. Montreuil et al. [9] presented a strategic framework for designing and operating agile manufacturing networks, enabling to collaboratively plan, control and manage day-to-day contingencies in a dynamic environment. Tso et al. [10] introduced the architecture of an agent-based collaborative service support system, which is able to carry out service requests in a manufacturing information network through some specially designed virtual agents. Cheng et al. [11] put forward an integrated framework for web-based design and manufacturing which is developed based on Java solution and CORBA-ORG broking technologies. Offodile and Abdel-Malek [12] introduced a framework for integrating IT and manufacturing strategies using the virtual manufacturing paradigm. Huang et al. [13] presented a holonic framework for virtual enterprises and control mechanisms of virtual enterprises under this framework. O’Sullivan [14] described an information architecture and associated toolset for understanding and managing the process of business development. Akkermansa and Horstc [15] discussed managerial aspects of information technology infrastructure standardisation in networked manufacturing firms and presented a strategic framework to guide managers in making sensible decisions regarding IT infrastructure standardisation, based on a number of pre-existing economic and management theories, such as transaction cost theory, organisational design and IT maturity growth stages. Jin et al. [16] presented a research on key application technologies and solutions, which includes a network safety strategy which ensures data transfer among the leaguer members; production data management based on Web/DOT (distributed object technology) and XML criteria which ensure data exchange in structure-variance characteristic environments; the network platform which provides the conversion service of different types of CAD files. Woerner and Woern [17] introduced a new web service based platform providing developed methods for co-operative plant production within virtual engineering.
To full realize the teleservice engineering in today’s globalized manufacturing industry and meet the current market situation and customer demand, a number of global manufacturing networks have been established by, among others, the Society of Manufacturing Engineer [18], Lockheed Martin (AIMSNET) [19] and 3M (the 3M Innovation Global Network) [20].
Today’s industries are facing serious structural problems brought about by their rapid development of overseas activities under a global integrated manufacturing environment. Service and maintenance are becoming extremely important practices for companies to maintain their manufacturing productivity and customer satisfaction in foreign regions. Due to the inherent problems of traditional help desk support, some companies have started developing web-based online customer service support system. Foo et al. [21] described an integrated help desk support for customer service via internet. Lee [7] discussed the concept and framework of a teleservice engineering system for the life cycle support of manufacturing equipment and products. A system for remote customer support has been created in the FCSA demonstrator of the Globerman 21 project [22]. The purpose of these systems above is to provide effective and responsive remote support to customers in the use, maintenance and troubleshooting of their equipment.
University of California is studying and developing a project called the Tele-Manufacturing Facility (TMF) which is to create an automated RP capability on the Internet. TMF allows users to easily submit jobs and have the system automatically maintain a queue. While it can automatically check many flaws in .STL files, and in many cases, fix them [23]. RP potentially offers great benefits when used during the design and manufacturing process. However, RP must be used in an effective manner if these benefits are to be fully exploited. The RP-novices have a lot of difficulties in getting a global view of the RP technique and in tackling well founded decision for investment or outsourcing of RP tasks because of the very quick appearance of new and improved processes in this field. In order to help novices select a suitable RP process, the rapid prototyping system selector has been developed by many researchers [24–27]. Quickparts. com, which is a privately held manufacturing services company dedicated to providing customers with an on-line E-commerce system to procure lowvolume and high-volume custom manufactured parts, has developed a QuickQuote system. The QuickQuote system enables customers to get instant, customerized quotations for the production of their parts [28]. 3D Systems Company, which is the earliest and biggest RP equipment manufacturer, has provided RP&M service for customer via Internet [29].
From these literatures survey, it is clear that most of studies mainly focused on the strategy and overall architecture of networked manufacturing as well as individual function module, there is still no comprehensive and banausic networked manufacturing service system to support rapid product development. Built on the emerging researches and our earlier work (e.g. Refs. [30,31]), a web-based manufacturing service system for rapid product development is to be established.
3. Architecture of the integrated system ofrapid product development
The development process from initial conceptual design to commercial product is an iterative process which includes: product design; analysis of performance, safety and reliability; product prototyping for experimental evaluation; and design modification. Therefore, any step of new product development process has a direct and strong influence on time-to-market. A good product development system must enable designers or design teams to consider all aspects of product design, manufacturing, selling and recycling at the early stage of a design cycle. So that design iteration and changes can be made easily and effectively. The more fluent the feedback is, the higher possibility success of the system has. Design for manufacturing (DFM) and concurrent engineering (CE) require that product and process design be developed simultaneously rather than sequentially [32].
The integrated system of rapid product development is composed of three modules: digital prototype, physical prototype and rapid tooling and functional part manufacturing system. The product development starts from the creation of a 3D model using a 3D CAD software package. At that stage the product geometry is defined and its aesthetic and dimensional characteristics are verified. The main function of digital prototype is to perform 3D CAD modelling. The product and its components are directly designed on a 3D CAD system (e.g. Pro/Engineer, Unigraphics, CATIA, IDEAS, etc.) during the creative design process. If a physical part is available, the model can be constructed by the reverse engineering (RE) technique. RE is a methodology for constructing CAD models of physical parts by digitizing an existing part, creating a digital model and then using it to manufacturing components [33]. RE can reduce the development cycle when redesigns become necessary for improved product performance. Pre-existing parts with features for improved performance can be readily incorporated into the desired part design. When a designer creates a new design using mock-up, it is also necessary to construct the CAD model of the mock-up for further use of the design data in analysis and manufacturing. The three primary steps in RE process are part digitization, features extraction, and 3D CAD modelling. Part digitization is accomplished by a variety of contact or non-contact digitizers. There are various commercial systems available for pa
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