《PrecisionMeasurementTechnology》主講人：趙慧、楊國(guó)星TianjinLightIndustryVocationalTechnicalCollegeI

IIIIIIVVVIFundamentalsofCoordinateMeasurementApplicationDimensionalErrorDetectionShapeErrorDetection

DirectionalErrorDetection

PositionalErrorDetection

RunoutErrorDetectionVII

CurveandSurfaceDetectionVIII

ExtendedContentTaskI:InspectionPlanning[TaskIntroduction]ThepositioningplatepartdrawingisshowninFigure2-1-1.Thispartincludesmultipledimensionalerrorinspectionitems,whichmustbemeasuredusingacoordinatemeasuringmachine(CONTURAG2,7/10/6)equippedwiththeRDS+VASTXXTprobesystem.Acorrespondinginspectionreportmustbegenerated.First,theinspectionitemsshouldbeorganized,andtheclampingschemeshouldbedetermined.[TaskReflection]Astheancientsayinggoes:"Thosewhodonotplanforthelongtermcannotplanforthepresent;thosewhodonotconsiderthewholepicturecannotmanageasingledomain."Beforeconductingmeasurementsinthisproject,itisessentialtosystematicallyorganizethemeasurementitemsanddevelopathoroughplantoensurebothmeasurementaccuracyandefficiency.Similarly,inhandlingothertasks,advanceplanningiscrucial,emphasizingtheimportanceofunderstandingthebroadercontextandoverallstrategy.[RelatedKnowledge]I.OrganizingMeasurementItemsBeforestartingthemeasurement,itisessentialtocarefullyreadandanalyzethetechnicaldrawings,organizethemeasurementitems,clearlyidentifytheelementstobecollected,andassignnumberstotheseelements.Thisprocessresultsinthemeasurementitemorganizationtable,asshowninTable2-1-1.Organizingthemeasurementitemsensuresastructuredandsystematicmeasurementprocess,effectivelyguidingsubsequentstepssuchasworkpiececlamping,probeselection,elementdefinition,andfeaturedefinition.Additionally,ithelpspreventomissionsintheinspectionprocess.SerialNumberMeasurementItemDescriptionRemarks1

2

[RelatedKnowledge]II.WorkpieceClampingandPositioning（1）Theclampedworkpieceshouldbepositionedasaccuratelyaspossibletoavoidcollisionswiththeprobeorstylusduringmeasurement.Forexample,alignthenormaldirectionofplanarelementswiththemachineaxisdirectionorensurethattheaxisofcylindricalelementsisparalleltothemachineaxis.（2）Themeasuredlocationsshouldnotbeobstructed.Theclampingpositionshouldbeselectedinareaswithoutmeasurementrequirementswheneverpossible.（3）Thereshouldbenoflexibleconnectionsbetweentheworkpiece,fixture,andmeasuringmachine.Methodssuchasusingdouble-sidedtapeormodelingclayshouldbeavoided.（4）Thesetupshouldallowforthecompletionofallelementmeasurementsinasingleclampingoperationtopreventtheneedforreclamping,ensuringbothmeasurementefficiencyandaccuracy.（5）Appropriateclampingforceshouldbeapplied—toolooseagripmaycauseworkpiecedisplacement,whileexcessiveclampingmayresultinworkpiecedeformation.[RelatedKnowledge]II.WorkpieceClampingandPositioningCommonclampingtoolsandmethodsincludeprecisionvises,three-jawchucks,flexiblefixtures,andspecializedfixtures.[TaskImplementation]I.OrganizingMeasurementItems[TaskImplementation]I.OrganizingMeasurementItems[TaskImp