XXXX機(jī)械設(shè)計制造及自動化 畢業(yè)設(shè)計 英文翻譯資料

1、天津工程師范學(xué)院2007屆本科生畢業(yè)設(shè)計 PAGE 12A NOVVEL IINTEGGRATEED SYYSTEMM FORR RAPPID PPRODUUCT DEVEELOPMMENTThis papeer prresennts aa novvel iinteggrateed syystemm of rapiid prroducct deeveloopmennt foor reeduciing the timee andd cosst off prooductt devveloppmentt. Thhe syystemm is compposedd of fourr buiildinng

2、 bloccks digiital prottotyppe, vvirtuual pprotootypee, phhysiccal pprotootypee andd rappid ttooliing mmanuffactuuringg systtem. It ccan aaid eeffecctiveely iin prroducct deesignn, annalyssis, prottotyppe, mmouldd, and manuufactturinng prrocesss deeveloopmennt byy inttegraatingg clooselyy thee varrio

3、uss advvanceed manuufactturinng teechnoologiies wwhichh invvolvee thee 3D CAD, CAEE, reeversse enngineeerinng, rrapidd prottotypping and rapiid tooolinng. FFurthhermoore, two actuual eexampples are provvidedd to illuustraate the appllicattion of tthis inteegratted ssysteem. TThe rresullts iindiccate

4、 thatt thee sysstem has a hiigh ppotenntiall to reduuce ffurthher tthe ccyclee andd cosst off prooductt devveloppmentt.Keywoords: Rappid pproduuct ddevellopmeent; rapiid prrotottypinng; iinteggrateed syystemm.1. InntrodductiionDue tto thhe prressuure oof innternnatioonal comppetittion and markket gg

5、lobaalizaationn in the 21stt cennturyy, thhere conttinuees too be stroong ddriviing fforcees inn inddustrry too commpetee effeectivvely by rreduccing manuufactturinng tiimes and costts whhile assuuringg higgh quualitty prodductss andd serrvicees. CCurreent iindusstriees arre faacingg thee neww chaal

6、lennges: quiick respponsee to busiinesss oppportuunityy hass beeen coonsidderedd as one of tthe mmost impoortannt facttors to eensurre coompanny coompettitivvenesss; mmanuffactuuringg inddustrry iss evoolvinng towaard ddigittalizzatioon, nnetwoork aand gglobaalizaationn. Thhereffore, neww prooductts

7、 muust bbe moree quiicklyy andd cheeaplyy devvelopped, manuufactturedd andd inttroduuced to tthe mmarkeet. In oorderr to meett thee demmand of rrapidd prooductt devveloppmentt, thhe vaariouus neew teechnoologiies suchh as reveerse engiineerring (RE), 3DD CADD, raapid prottotypping (RP), annd rapiid

8、tooolinng (RRT) hhave emerrged and are regaardedd as key enabblingg toools wwith the abillity to sshortten tthe pproduuct ddevellopmeent aand mmanuffactuuringg timme. FFor eexampple, it hhas bbeen claiimed thatt RP can cut new prodduct deveelopmment costts byy up to 770% and the timee to markket bby

9、 900%.1 In tthe fform of aa bettter desiign, moree dessign posssibillitiees, a 3DD CADD moddel ccan bbe shhown to tthe ccustoomer for apprrovall andd preeventts misuunderrstanndinggs. AA virrtuall proototyypingg is emplloyedd to guidde inn opttimizzatioon of tthe pproduuct ddesiggn annd maanufaactur

10、ring proccess plannningg, whhich may resuult iin the accuuratee dettermiinatiion oof thhe prrocesss paarameeterss, annd reeducee thee nummber of costtly pphysiical prottotyppe itterattionss. Raapid toolling techhniquue offferss a ffast and low costt metthod to pproduuce mmouldds, aand sshowss a hhig

11、h poteentiaal foor faasterr ressponsse too markket ddemannds. Whenn prooperlly inntegrratedd amoong 33D CAAD, CCAE, RE, RP aand RT, thesse teechnoologiies wwill playy a mmuch moree impportaant rrole to rreducce fuurtheer thhe deveelopmment cyclle annd coost oof thhe prroducct prroducctionn. Onn thee

12、 bassis oof abbove techhnoloogiess, a noovel inteegratted ssysteem off rappid pproduuct ddevellopmeent iis too be founnded so aas too meeet thhe reequirremennt off rappid pproduuct ddevellopmeent.2. Arrchittectuure oof thhe Inntegrratedd Devveloppmentt SysstemThe ddevellopmeent pproceess ffrom initt

13、ial concceptuual ddesiggn too commmerccial prodduct is aan iterrativve prrocesss whhich inclludess: prroducct deesignn; annalyssis oof peerforrmancce, ssafetty annd reliiabillity; prooductt proototyypingg forr expperimmentaal evvaluaationn; annd deesignn moddificcatioon. Therreforre, aany sstep of t

14、the nnew pproduuct ddevellopmeent pproceess hhas aa dirrect and stroong iinfluuencee on timee-to-markket iin shhort ordeer. AA goood prroducct deeveloopmennt systtem mmust enabble ddesiggnerss or desiign tteamss to conssiderr alll asppectss of prodduct desiign, manuufactturinng, sselliing aand rrecy

15、cclingg at the earlly sttage of tthe ddesiggn cyycle. So tthat desiign iiteraationn andd chaangess cann be madee eassily and effeectivvely. Thee morre flueent tthe ffeedbback is tthe hhigheer poossibbilitty off succcesss thee sysstem has. Dessign for manuufactturinng (DDFM) and conccurreent eenginne

16、eriing (CE) neceessittate thatt prooductt and proccess desiign bbe deevelooped simuultanneoussly rratheer thhan ssequeentiaally. The inteegratted ssysteem off rappid pproduuct ddevellopmeent iis coompossed oof foour mmodulles: digiital prottotyppe, vvirtuual pprotootypee, phhysiccal pprotootypee and

17、d rappid ttooliing.TThe pproduuct ddevellopmeent sstartts frrom tthe ccreattion of aa 3D CAD modeel ussing a CAD softtwaree pacckagee. Att thaat sttage, thee prooductt geoometrry iss deffinedd andd itss aestthetiic annd diimenssionaal chharaccteriisticcs arre veerifiied. The mainn funnctioon off dig

18、gitall prottotyppe iss to perfform 3D CCAD mmodelllingg. Thhe CAAD moodel is rregarrded as aa centtral compponennt off thee whoole ssysteem orr proojectt infformaationn basse whhich meanns thatt in all desiign, anallysiss andd mannufaccturiing aactivvitiees thhe saame ddata is uutiliized. The proddu

19、ct and its compponennts aare ddirecctly desiignedd on a 3DD CADD sysstem (e.gg.Proo/Enggineeer, UUnigrraphiics, CATIIA, IIDEASS, ettc.) duriing tthe ccreattive desiign. If aa physsicall parrt iss reaady, the modeel caan bee connstruuctedd by the reveerse engiineerring techhniquue. RRE iss a mmethood

20、oloogy ffor cconsttructting CAD modeels oof phhysiccal ppartss by digiitiziing aan exxistiing ppart, creeatinng a digiital modeel annd thhen uusingg it to mmanuffactuure compponennts. RE ccan rreducce thhe deeveloopmennt cyycle whenn reddesiggns bbecomme neecesssary for imprrovedd prooductt quaality

21、y. Prreexiistinng paarts withh feaaturees foor immprovved perfformaance can be rreadiily iincorrporaated intoo thee dessiredd parrt deesignn. Thhereffore, it is vvery usefful iin crreatiing tthe CCAD mmodell of an eexistting partt wheen thhe enngineeerinng desiign iis loost oor haas goone tthrouugh

22、mmany desiign cchangges. Whenn a ddesiggner creaates a neew deesignn usiing mmock-up, it iis allso nnecesssaryy to consstrucct thhe CAAD moodel of tthe mmock-up ffor ffurthher uuse oof thhe deesignn datta inn anaalysiis annd maanufaacturring. The threee prrimarry stteps in RRE prrocesss arre paart d

23、digittizattion, feaaturees exxtracctionn, and CAD modeellinng. PPart digiitizaationn is accoompliishedd by a vaarietty off conntactt or non-conttact digiitizeers. Therre arre vaariouus coommerrciall sysstemss avaailabble ffor ppart digiitizaationn. Thesse syystemms raange fromm cooordinnate meassuri

24、nng maachinne (CCMM), lasser scannnerss to ultrrasonnic ddigittizerrs. TThey can be cclasssifieed innto ttwo bbroadd cattegorries: conttact and non-conttact. Lasser ttrianngulaationn scaannerr (LTTS), magnneticc ressonannce imagges (MRI), annd coomputter ttomoggraphhy (CCT) aare ccommoonly usedd as

25、non-conttact deviices. Conntactt diggitizzers mainnly hhave CMM and crosss-seectioonal imagging meassuremment (CIMM). FFeatuure eextraactioon iss norrmallly acchievved bby seegmenntingg thee diggitizzed dataa andd cappturiing ssurfaace ffeatuures suchh as edgees. PPart modeellinng iss fullfileed thh

26、rouggh fittting a vaarietty off surrfacees too thee seggmentted ddata poinnts.In orrder to rreducce thhe itterattionss of desiign-pprotootypee-tesst cyycless, inncreaase tthe prodduct proccess and manuufactturinng reeliabbilitty, iit iss neccessaary tto guuide in ooptimmizinng the prodduct desiign a

27、and mmanuffactuuringg proocesss thrroughh virrtuall proototyype (VP). VP iis a proccess of uusingg 3D CAD modeel, iin liieu oof a physsicall proototyype, for testting and evalluatiion oof sppeciffic ccharaacterristiics oof a prodduct or aa mannufaccturiing pproceess. It iis offten carrried out by CC

28、AE aand vvirtuual mmanuffactuuringg sysstem. Commputeer aiided engiineerring (CAEE) annalyssis iis ann inttegraal paart oof tiime-ccomprressiion ttechnnologgies. Variious softtwaree toools aavaillablee (i.e. AANSYSS, MAARC, I-DEEAS, AUTOOFORMM, DYNAAFORMM, ettc.) can speeed upp thee devveloppmentt o

29、f new prodductss by inittiatiing desiign ooptimmizattion befoore pphysiical prottotyppes aare bbuiltt. Thhe CAAD moodelss cann be trannsferrred to aa CAEE envvironnmentt forr an anallysiss of the prodduct funcctionnal pperfoormannce and of tthe mmanuffactuuringg proocessses ffor pproduucingg thee pr

30、ooductts ccompoonentts. It hhas aalso provven tto bee of greaat vaalue in tthe ddesiggn opptimiizatiion oof paart ggeomeetry, to ddeterrminee itss dimmensiions and to ccontrrol wwarpaage aand sshrinnkagee whiile mminimmizinng proccess-induuced resiiduall strressees annd deeformmatioons. Virttual man

31、uufactturinng syystemm (VM) is the natuural exteensioon off CAEE. Itt simmulattes tthe pproduuct ffuncttionaalityy andd the proccessees foor prroduccing it ppriorr to the deveelopmment of pphysiical prottotyppes. VM eenablles aa dessigneer too vissualiize aand ooptimmize a prroducct prrocesss wiith

32、aa sett of proccess paraameteers. The visuualizzatioon off a vvirtuuallyy simmulatted ppart prioor too phyysicaal fabrricattion helpps too redduce unwaantedd proototyype iiteraationns. TThereeforee, a prodduct virttual manuufactturinng syystemm mayy ressult in aaccurrate deteerminnatioon off thee pr

33、oocesss paraameteers, and reduuce tthe nnumbeer off cosstly physsicall proototyype iiteraationns. 33D CAAD modeel annd VPP alllow mmost probblemss witth unnfittting to bbecomme obbviouus eaarly in tthe prodduct deveelopmment proccess. Asssembllies can be vveriffied for inteerferrencee as VP can be e

34、exerccisedd thrroughh a rrangee of taskks. SStruccturee andd theermall anaalysiis caan bee perfformeed onn thee samme moodel emplloyinng CAAE apppliccatioons aas weell aas siimulaatingg downn-strream manuufactturinng prrocessses. It is cclearr thaat VPP inccreasses pproceess aand prodduct reliiabill

35、ity. Altthouggh VPP is inteendedd to ensuure tthat unsuuitabble ddesiggns aare rejeectedd or modiifiedd, inn manny caases, a vvisuaal annd phhysiccal eevaluuatioon off thee reaal coomponnent is nneedeed. TThis ofteen reequirres pphysiical prottotyppe too be prodducedd. Heence, oncee thee VP is ffini

36、sshed, thee moddel mmay ooftenn be sentt dirrectlly too phyysicaal faabriccatioon. The CCAD mmodell cann be direectlyy connvertted tto thhe phhysiccal pprotootypee usiing aa RP ttechnniquee or highh-speeed mmachiiningg (HSSM) pproceess. The 3D CCAD mmodell is to be eexporrted not onlyy in the STL fo

37、rmmat wwhichh is conssiderred tthe dde faacto stanndardd for inteerfaccing CAD and RP ssysteems, but alsoo in the NC ccodinng whhich can be uused by HHSM. HSM has a pootenttial for rapiid prroduccing plasster or wwoodeen paatterrn foor RT. RP iis a new formming proccess whicch faabriccatess phyysica

38、al paarts layeer byy layyer uunderr compputerr conntroll dirrectlly frrom 33D CAAD moodelss in a veery sshortt timme. IIn coontraast tto tradditioonal machhininng meethodds, tthe mmajorrity of rrapidd proototyypingg sysstemss tennd too fabrricatte paarts baseed onn addditivve maanufaacturring procce

39、ss, ratther thann subbtracctionn or remooval of mmaterrial. Theerefoore, thiss typpe off fabbricaationn is uncoonstrraineed byy thee limmitattionss attrributted tto coonvenntionnal mmachiiningg appproacches. Thee appplicaationn of RP techhniquue ass a uusefuul toool ccan pproviide bbeneffits throoug

40、hoout tthe pproceess oof deeveloopingg new prodductss. Sppecifficallly, therre arre seeriouus beenefiits tthat RP ccan bbringg in the areaas of mmarkeet reesearrch, salees suupporrt, ppromootionnal mmaterrial, andd thee eveer-immporttant prodduct launnch. Physsicall RP can alsoo beccome a poowerfful

41、 ccommuunicaationns toool tto ensuure tthat everryonee invvolveed inn thee devveloppmentt proocesss fullly uunderrstannds aand apprreciaates the prodduct beinng deevelooped. Hennce, it ccan hhelp to rreducce suubstaantiaally the inevvitabble rriskss in the routte frrom pproduuct cconceept tto coomme

42、rrciall succcesss, and helpp shoortenn timme-too-marrket, impprovee quaalityy andd redduce costt. Ovver tthe lastt 20 yearrs, RRP maachinnes hhave beenn widdely usedd in induustryy. Thhe RPP metthodss commmerciiallyy avaailabble iincluude SStereeolitthgraaphy (SLAA), SSelecctivee Lasser SSinteeringg

43、 (SLSS), FFusedd Depposittion Manuufactturinng (FFDM), Lamminatted OObjecct Maanufaacturring (LOMM), BBalliisticc Parrticlle Maanufaacturring (BMPP), aand TThreee-Dimmensiionall Priintinng (3D prinntingg), eetc.Once the desiign hhas bbeen acceeptedd, thhe reealizzatioon off thee prooducttion linee r

44、eppreseents a maajor taskk witth a longg leaad tiime bbeforre anny prroducct caan bee putt to the markket. In ppartiiculaar, tthe pprepaaratiion oof coompleex tooolinng iss usuuallyy in the critticall pathh of a prrojecct annd haas thhereffore a diirectt andd strrong inflluencce onn timme-too-marrke

45、t. In oorderr to reduuce tthe pproduuct ddevellopmeent ttime and costt, thhe neew teechniique of RT hhas bbeen deveelopeed. RRT iss a ttechnniquee thaat caan trransfform the RP ppatteerns intoo funcctionnal ppartss, esspeciiallyy mettal ppartss. Itt offfers a faast aand llow ccost methhod tto prrodu

46、cce moullds aand ffuncttionaal paarts. Furrtherrmoree, thhe inntegrratioon off botth RPP andd RT in ddevellopmeent sstrattegy prommotess thee impplemeentattion of cconcuurrennt enngineeerinng inn comppaniees. NNumerrous proccessees haave bbeen deveelopeed foor prroduccing diess froom RPP systtem. Th

47、e RT mmethoods ccan ggenerrallyy be diviided intoo dirrect and indiirectt tooolingg cateegoriies, and alsoo sofft (ffirm) andd harrd tooolinng suubgrooups. Inddirecct RTT reqquirees somee kinnds oof maasterr pattternns, wwhichh cann be madee by convventiionall metthodss (e.g. HSM), orr morre coommon

48、nly bby ann RP proccess suchh as SLA oor SLLS. DDirecct RTT, ass thee namee sugggestts, iinvollves the manuufactturinng off a ttool caviity ddirecctly on aa RP systtem, hencce elliminnatinng thhe inntermmediaate sstep of ggenerratinng a patttern. Sofft tooolinng can be oobtaiined via repllicattion f

49、romm a pposittive patttern or mmasteer. SSoft toolling is assoociatted wwith low costts; uused for low voluume pproduuctioon annd usses mmaterrialss thaat havee loww harrdnesss leevelss succh ass silliconnes, epoxxies, loww melltingg poiint aalloyys, eetc. RTV siliiconee rubbber moullds, epoxxy moou

50、ldss, meetal spraayingg mouulds, etcc. arre soome of tthesee typpicall sofft mooldinngs. Hardd tooolingg is assoociatted wwith highher vvolumme off prooducttion, and the use of mmaterrialss of greaater harddnesss. Keeltoool prrocesss, QQuickkcastt proccess, andd thee ExppresssTooll proocesss aree so

51、mme off theese hhard toollingss. Ellectrricall discchargge maachinning (EDMM) seeems to bbe ann intteresstingg areea inn whiich rrapidd tooolingg findds a poteentiaal apppliccatioon. SSome methhods of mmakinng EDDM ellectrrodess bassed oon RP ttechnniquee havve deevelooped, succh ass abrradinng prro

52、cesss, ccoppeer ellectrroforrmingg andd net shappe caastinng, eetc. On tthe bbasiss of the abovve teechniiquess, a noveel inntegrratedd systtem oof raapid prodduct deveelopmment is tto bee prooposeed. IIts ooveraall aarchiitectture is showwn inn Figg. 1.3. Caase SStudiies3.1. Casee stuudy 11: Immpel

53、llerA tottal oof thhirtyy plaasticc imppelleers, withh a rrelattivelly coompleex geeomettry, weree reqquireed by aa cusstomeer wiithinn fiffteenn worrkingg dayys frrom tthe rreceiipt oof a 2D CCAD mmodell. Therre weere mmany facttors to bbe coonsidderedd in deciidingg thee mosst appproppriatte roout

54、e for prodducinng thhe immpelllers. Theese ffactoors mmainlly innvolvved ccost, leaad-tiime, the numbber of ppartss reqquireed, tthe ffinall matteriaal foor thhe paarts, andd thee parrt geeomettry. In ordeer too maxximizze thhe beenefiits iin teerms of ttime and costt redductiion ffor tthe ppartss,

55、it wwas ddecidded tto usse siilicoon ruubberr mouuld aand tthe ppartss werre evventuuallyy prooduceed by vvacuuum caastinng prrocesss. SSiliccon rrubbeer moould is aan eaasy, relaativeely iinexppensiive and fastt wayy to fabrricatte prrotottype or ppre-pproduuctioon toools. It can be uutiliized for

56、moulldingg parrts iin waax, ppolyuurethhane, ABSS, annd a few epoxxy maateriials. Thee proocesss is bbest suitted ffor pprojeects wherre foorm, fit, or funcctionnal ttestiing ccan bbe doone wwith a maateriial wwhichh mimmics the charracteeristtics of tthe pproduuctioon maateriial. The castting partt

57、s wiith ffine detaails and veryy thiin waalls can be eeasilly annd raapidlly prroducced. The wholle prrocesss fllow iinvollved the 3D CCAD mmodelllingg, prroduccing mastter ppatteern (RP prottotyppe), siliicon rubbber mmouldd, annd caastinng grreen partts. TThe ttime sequuencee for the fabrricattion

58、 of iimpelllerss wass desscribbed aas foollowws. DDue tto thhe coompleexityy of the impeellerr, thhe taask oof geeneraatingg thee 3D CAD modeel ussing Pro/Engiineerr sofftwarre packkage tookk almmost 3 caalenddar ddays. Thee masster patttern for thiss proojectt wass buiilt on aa SPSS 6000 macchinee

59、in 2 caalenddar ddays. SL proccess was chossen bbecauuse iit waas coost effeectivve annd thhe suurfacce fiinishh wass goood. TThe nnext stepp invvolveed crreatiing aa rooomtemmperaaturee vulccanizzed (RTV) silliconne ruubberr molld whhich was comppleteed wiithinn an aaddittionaal 3 caleendarr dayys.

60、 FFinallly, the ABS mateerialls weere ccast intoo silliconn rubbber moulld unnder the vacuuum ccastiing ccondiitionn, annd thhe grreen partts weere aachieeved in 44 callendaar daays. The requuiredd 30 compponennts wwere prodducedd succcesssfullly annd comppleteed inn 12 caleendarr dayys. TThe pprima