CADCAM 原理与应用（英文版）课件 Part 3 Reverse Engineering

主讲人：康兰CAD/CAM:PrinciplesandApplicationsCAD/CAM原理与应用CollegeofMechanicalandElectricalEngineering,HohaiUniversity（河海大学机电工程学院）

Part3:ReverseEngineering3.1Whatisreverseengineering(RE)?Contents3.2WhyREisneeded?3.5

ProcessofRE?3.3REhardware3.4REsoftware3.6REmodelingmethods3.7REapplications3.1WhatisReverseEngineering(RE)?WhatisReverseEngineering(RE)?Broadlyspeaking,reverseengineeringistheprocessofdiscoveringthetechnologicalprinciplesofadevice,object,orsystemthroughanalysisofitsstructure,function,andoperation.Inthiscourse,REreferstotheprocessofretrievingtheoriginalgeometryfromanexistingpartbyscanning,modifyingandrebuilding.3.2WhyisREneeded?WhyisREneeded?Theoriginalmanufacturernolongerexistsortheydon’tproducetheproduct,butacustomerneedstheproduct.Theoriginalproductdesigndocumentationhasbeenlostorneverexisted.Inspectionand/orqualitycontrol–comparingafabricatedparttoitsCADmodelortoastandarditem.Creating3Ddatafromamodelorsculptureforanimationingamesandmovies.Creating3Ddatafromanindividualmodelorsculpturetocreate,scale,orreproduceartwork.Generatingdatatocreatedentalorsurgicalprosthetics,tissueengineeredbodyparts,orforsurgicalplanning.…………3.2WhyREisneeded?3.3REhardwareREhardwareContactScannersCoordinateMeasuringMachines(CMM)PortableMeasuringArmsGantryCMM3.3REhardwareNoncontactscanners3.3REhardwareScanningprocess3.3REhardwareAboutrebuildingthemodelofapartfromscanninganassembly.Anexample:3.3REHardwareREsoftwareImagewareGeomagicStudioCopyCADRapidFormMost3DsoftwarealsoprovidesfunctionstoacceptandeditdatafromREsoftwareordirectlyfrom3Dscanners.3.4RESoftware3.5ProcessofREREModelingMethods3.6REModelingMethodsRebuildmodelbyfittingsurfacestoidentifiedfeatures3.6REModelingMethodsThekeystepforthismethodistosegmentpointclouddataintosmallregion,eachregionhassameattribute.Segmentingdatamethod:Example1:Setcertainconditions,suchasradiusofcurvature,thensegmentdatabydetectedsharpedges.3.6REModelingMethodsExample2:"regiongrowing"approach3.6REModelingMethodsExample3:Slicingthedata3.6REModelingMethodsExample3:Multi-directionalslicingManyways…..,moreresearchworkonthistopicstillcontinue.3.6REmodelingmethodsREApplicationsInaerospaceandautomotiveindustries.3.7REApplicationsMoulddesignManufacturingerrorinspectionBiomedicalapplicationHumanbodyshapemeasurementandrebuilding3.7REApplicationsRestoration/RepairofculturalrelicsMeasurementJointdataResearchershadtriedtorebuildthemodeloftheSaintVojtechlocatedonCharlesbridgeinPragueofCzechRepublic.3.7REApplicationsFinalcloudsof