现代机械工学(虚拟机床)课件

虚拟机床VirtualMachineTool天津大学机械工程学院OutlinesDemandsforModernMachinetoolsConceptsandDefinitionsVMTvs.ProductR&DModernMachineToolandItsRequirementsIntegrateddevelopmentofmodernmachinetoolswithvirtualprototypesKeysofVirtualMachineToolFunctionHighAccuracyHighEfficiencyDemandsforModernMachinetoolsLightweightofmovingcomponentsHighstaticanddynamicstiffnessVirtualPrototyping“VirtualPrototyping(VP)isarelativelynewtechnologywhichinvolvestheuseofVirtualReality(VR)andothercomputertechnologiestocreatedigitalprototypes.”—Gowda

etal.(MichiganStateUniversity)“Byvirtualprototyping,werefertotheprocessofsimulatingtheuser,theproduct,andtheircombined(physical)interactioninsoftwarethroughthedifferentstagesofproductdesign,andthequantitativeperformanceanalysisoftheproduct.”—Songetal.(UniversityofPennsylvania)ConceptsandDefinitionsVirtualPrototyping（cont-）“Inthemechanicalengineeringdefinitionofvirtualprototyping(VPME),theideaistoreplacephysicalmock-upsbysoftwareprototypes.Thisincludesalsoallkindsofgeometricalandfunctionalsimulations,whetherornotinvolvinghumans.”—AntoninoandZachmann(BMW)Digitalmock-up(DMU)Arealisticcomputersimulationofaproductwiththecapabilityofallrequiredfunctionsfromdesign/engineering,manufacturing,productservice,uptomaintenanceandproductrecycling.ConceptsandDefinitions(cont-)Prototypeafull-scalemodelofastructureorpieceofequipment,usedinevaluatingform,design,fit,andperformance.Mock-upascalemodel,oftenfull-size,ofastructure,apparatus,orvehicle;usedforstudy,training,ortestingandtodetermineiftheapparatuscanbemanufacturedeasilyandeconomically.”Prototype～Mock-up——TheAcademicPressDictionaryofScienceandTechnologyConceptsandDefinitions(cont-)“Virtualprototype,ordigitalmock-up,isacomputersimulationofaphysicalproductthatcanbepresented,analyzed,andtestedfromconcernedproductlife-cycleaspectssuchasdesign/engineering,manufacturing,service,andrecyclingasifonarealphysicalmodel.Theconstructionandtestingofavirtualprototypeiscalledvirtualprototyping(VP).”——G.GaryWang(UniversityofManitoba)ConceptsandDefinitions(cont-)VirtualMachineTool(VMT)VirtualPrototypingofMachiningtool

Thevirtualprototypeofamachinetoolisacomputersimulationmodelofthephysicalproductthatcanbepresented,analysedandtestedlikearealmachine.——C.Brecher(AachenUniversityofTechnology)ConceptsandDefinitions(cont-)VMTvs.ProductR&DModernMachineToolandItsRequirementsToensurethatthefirstphysicalprototypeofthemachinetoolmeetstherequirementsinthebestpossibleway,itisessentialthateverydesignstepisevaluatedwithsimulationsofthevirtualprototype.Integrateddevelopmentofmodernmachine

toolswithvirtualprototypes

KeysofVirtualMachineToolKinematicsstudieswithrigidmulti-bodysimulation(conceptdesign)Finite-Element-AnalysisandstructuraloptimizationCoupledflexibleMulti-Body-SimulationCalibrationoftheSimulationModelsOptimizationoftheSimulationModelsKinematicsStudiesMethod&ToolRigidmulti-bodysimulationOptimizationSteps&TasksDeterminationoftheappropriatekinematictopologyDeterminationoftherightgeometricdimensions——ApoortopologywhichisoptimallydesignedmayperformbetterthanamechanismwithappropriatetopologybutpoordesignKinematicsStudies(cont-)OptimizationofthekinematicperformanceKinematicsStudies(cont-)Rigidmulti-bodysimulationAssemblyanalysisKinematicanalysisu,v,

aDynamicanalysis-F

ma,

v,uInversedynamicanalysis-u,v,a

FStaticanalysis——analyzethekinematicbehavior,determineloadhistories,helpstochooseproperelementsordetectweakspotsofamachinetoolintheearlydesignstages.KinematicsStudies(cont-)Finite-Element-AnalysisandStructuralOptimizationStaticanalysisBeingusedtodeterminethedisplacements,stresses,strains,andforcesinstructuresorcomponentscausedbyloadsthatdonotinducesignificantinertiaanddampingeffects.Steadyloadandresponseconditionsareassumedinstaticanalysis;i.e.,theloadsandthestructure’sresponseareassumedtovaryslowlywithtime.Finite-Element-AnalysisandStructuralOptimization(cont-)DynamicanalysisAllowstheexaminationofastructurewithrespecttotime-varyingeffects.Formachinetoolsthemostimportantaspectistheanalysisofnormalmodedynamicstodeterminethevibrationcharacteristics(naturalfrequenciesandmodeshapes)ofastructureoramachinecomponentinthefrequencydomain,aswellasanalysisoftimedomainresponseofthemachineFinite-Element-AnalysisandStructuralOptimization(cont-)HeatanalysisTheinfluenceofheatsourcesonthemachine’sstructure.3primarymodesofheattransfer:conduction,convectionandradiationFinite-Element-AnalysisandStructuralOptimization(cont-)Finite-Element-AnalysisandStructuralOptimization(cont-)ResultsinaFinite-Element-AnalysisDeformations,e.g.deflectionofthetoolcentrepoint(TCP)underprocessloads,deflectionofguideways,reactionforces,e.g.forcesinbearingsorguidingsystemsLinearnormalmodesofvibrationFlexibilityfrequencyresponse(withlimitation)Stressdistribution,e.g.inhighlyloadedtoolinterfacesunderadditionalrotationalloadsTemperaturedistribution,thermalfluxesandresultingdeformationsFinite-Element-AnalysisandStructuralOptimization(cont-)OptimisationofstructuralcomponentsThetopologyoptimisation

isusedtodefinethebestmaterialdistributioninagivendesignspace.Thusthismethodismainlyusedintheearlydesignstagessupportingtheengineerinfindingadesignconceptwithregardtogivendemands.Theparameteroptimisation

isusedfortheoptimisationofmoredetaileddesignsofmachinetools,tooptimiseparametersofstructuralcomponentsconsideringdifferentconstraints,e.g.maximalalloweddeformation.Finite-Element-AnalysisandStructuralOptimization(cont-)Finite-Element-AnalysisandStructuralOptimization(cont-)Finite-Element-AnalysisandStructuralOptimization(cont-)Workflowofthecoupledhybridmulti-bodysimulationwithtopologyoptimisationFinite-Element-AnalysisandStructuralOptimization(cont-)ParameteroptimisationofamachiningcentreCoupledSimulationofStructuralDynamicsandControlLoopsofMachineToolsWhyCoupledSimulation?

——InteractionsbetweenstructuraldynamicsandfeeddrivecontrolsCoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)MethodsofcoupledsimulationofstructuraldynamicsandcontrolloopsCoupledrigidmulti-bodysimulationCoupledFinite-ElementsimulationCoupledflexiblemulti-bodysimulationCoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)CoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)Coupledsimulationofarigidmulti-bodymodelandcontrolloopmodelsofaPKMmachinetoolCoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)CoupledFEA-simulationwithcontrolloops(positionerrorsimulationofx-slideofaturningcentre)CoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)Integrationofstructuralandcontrollermodels——tooptimisethemachinetool’smechanicalcomponentsaswellasthecontrollawsCoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)Couplingofflexiblemulti-bodymodelsandcontrolloopsCoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)FlexibleMulti-BodySystemModelforcoupledsimulationCoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)CoupledSimulationofStructuralDynamicsandControlLoopsofMachineTools(cont-)Accuracyofthesimulatedresults?Correctestimationofthesimulationparameters?(dynamicstiffness&dampingparametersetc.)MeasurementsofthedynamicbehaviorofsimilarmachinetoolsorcomponentsComparethesimulationwithmeasurementandregulatethemodelparameters(stiffness-and

damping-coefficients)tomakethesimulationagreetothemeasurementsCalibrationofthe

simulation

modelsTheFrequencyResponseFunction(FRF)ofthecomplianceatthetoolcentrepoint(TCP)--frequen