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1、摘要逆向工程技術(shù)是進(jìn)行產(chǎn)品設(shè)計(jì)、開發(fā)和創(chuàng)新的先進(jìn)制造技術(shù),其中產(chǎn)品外表的數(shù)據(jù)采集和模型重構(gòu)是逆向工程的兩項(xiàng)關(guān)鍵技術(shù)。本文圍繞數(shù)據(jù)采集和模型重構(gòu)兩個(gè)方面,歸納總結(jié)了國內(nèi)外研究現(xiàn)狀,在此基礎(chǔ)上研究了逆向工程的關(guān)鍵技術(shù)。零件的數(shù)字化是通過特定的測量設(shè)備和測量方法獲取零件表面離散點(diǎn)的幾何坐標(biāo)數(shù)據(jù),在這基礎(chǔ)上進(jìn)行復(fù)雜曲面的建模、評(píng)價(jià)、改進(jìn)和制造。因而,高效、高精度地實(shí)現(xiàn)樣件表面的數(shù)據(jù)采集至關(guān)重要。文本正是基于此,研究了當(dāng)前工業(yè)中常用的三坐標(biāo)測量機(jī)的自適應(yīng)測量路徑規(guī)劃問題,在實(shí)現(xiàn)“自學(xué)習(xí)”式測量、圓弧插值法、多項(xiàng)式法和四次多項(xiàng)式法的基礎(chǔ)上,提出了曲
2、率連續(xù)預(yù)測法進(jìn)行三坐標(biāo)自適應(yīng)測量。通過編程,最終實(shí)現(xiàn)了上述方法的實(shí)際測量,并用兩個(gè)實(shí)例驗(yàn)證了曲率連續(xù)預(yù)測法的有效性和精確性。實(shí)物的三維CAD模型重構(gòu)是逆向工程中最關(guān)鍵、最復(fù)雜的一環(huán),因?yàn)楹罄m(xù)產(chǎn)品加工制造、快速原型制造、虛擬制造仿真、工程分析和產(chǎn)品的再設(shè)計(jì)等應(yīng)用都需要CAD數(shù)學(xué)模型的支持。這些應(yīng)用都不同程度地要求重構(gòu)的CAD模型能準(zhǔn)確的還原實(shí)物樣件。本文正是以實(shí)物零件模型重構(gòu)為基礎(chǔ),討論并研究了模型重構(gòu)的方法及步驟,主要討論了曲線和曲面的重構(gòu)方法。最后還對(duì)重構(gòu)模型的精度進(jìn)行了評(píng)價(jià)。關(guān)鍵詞:逆向工程;三坐標(biāo)測量機(jī);曲率連續(xù)預(yù)測法;自適應(yīng)測量
3、;模型重構(gòu)AbstractReverseengineering(RE)technologyisaburgeoningadvancedmanufacturingtechnologyusedtodesignandexploitnewproducts.Shapedataacquiringanddataprocessingaretwokeyproblems.Thispaperconcentratesonshapedataacquiringanddataprocessingandauthormakestheresearchonsomecurren
4、tproblemsinreverseengineeringtechnologybasedonconcludingandreviewingpreviouswork.Thepans’digitizationisacquiredgeometriccoordinatedataofdiscretepointsinparts’surface,anddoescomplexsurfacemodeling,evaluation,improvementandmanufactureonthisbasis.Thus,it’Simportantforimplem
5、entingdatacollectionofparts’surfacehighefficientlyandhighprecision.Thispaperisbasedonthis,researchingadaptivepathplanningproblemofCMM.Afterrealizing“self-study”typemeasurement,circularinterpolation,polynomialmethodandfour-polynomialmethod,thispaperpresentscurvaturecontin
6、uouspredictionmethodforCMMmeasurement.Thoughprogramming,werealizetheactualmeasurementabouttheabovemethodsfinally,andverifytheeffectivenessandaccuracyofthecurvaturecontinuouspredictionmethodthoughtwoexamples.It’Sthemostcriticalandmostcomplexaspectoftheobjects’three—dimens
7、ionalCADmodelreconstructioninreverseengineering,sincetheyneedthesupportofCADdigitalmodelforfollow-upproductsmanufacturing,rapidprototyping,virtualmanufacturingsimulation,engineeringanalysisandproductre—design.TheseapplicationsrequirethatthereconstructedCADmodelCanaccurat
8、elyrestorethesampleofobjectfordifferentdegrees.Thispaperdiscussesandresearchesmodelreconstructionmethod