SAE J2264-1995 CHASSIS DYNAMOMETER SIMULATION OF R

SAETechnicalStandardsBoardRulesprovidethat:“ThisreportispublishedbySAEtoadvancethestateoftechnicalandengineeringsciences.Theuseofthisreportisentirelyvoluntary,anditsapplicabilityandsuitabilityforanyparticularuse,includinganypatentinfringementarisingtherefrom,isthesoleresponsibilityoftheuser.”SAEreviewseachtechnicalreportatleasteveryfiveyearsatwhichtimeitmaybereaffirmed,revised,orcancelled.SAEinvitesyourwrittencommentsandsuggestions.QUESTIONSREGARDINGTHISDOCUMENT:[phone]FAX:[phone]TOPLACEADOCUMENTORDER;[phone]FAX:[phone]SAEWEBADDRESS—ThisDocumenthasnotchangedotherthantoputitintothenewSAETechnicalStandardsBoardformat.Electricchassisrolldynamometersprovidethemeansforrapid,accurate,automaticadjustmentofdynamometerloadingtosimulatevehicleroadloadovertheentirespeedrangethroughwhichthevehicleistested.Precisecalibrationofchassisrolltorquemeasurement,speedinstrumentation,andbaseinertia,togetherwithcontrolsemployingvalidalgorithms,haveresultedinaccuratedynamometerloadcoefficientmeasurementsusingcoastdowntechniqueswithoutrequiringonerouscomputationanddatamanipulationbyusers.Variabilityofeachdynamometerandbetweendynamometersislow,permittingloadcoefficientsobtainedononedynamometertobeusedonothersimilardynamometers.Toachievethisinterchangeabilityofloadingcoefficients,operationalfactorsarespecifiedwiththeobjectiveofkeepingtestvariabilityatthelowlevelsofthedynamometer.Thisprocedurehasbeendevelopedinconjunctionwiththeintroductionofthe1.219m(48in)diametersingle-rollelectricdynamometerforvehicleemissionsandfueleconomytesting.Themethodologyisgenerictoanydynamometercapableofcarryingouttheroadloadderivationdescribed,regardlessofrollsize,geometry,orrollsurfaceroughness.However,thisprocedureisintendedtoprovideastandardofbestpracticeforallvehicletestingrequiringaccurateroadloadsimulation.Consequently,the1.219mrolldiameterwithsmoothrollsurfaceisspecifiedtominimizevariabilityinresultsoftestsdoneondifferentdynamometers.Thiseliminatesvariabilityresultingfromrollgeometryandsurfaceeffectsontireenergylossandslipchangesoccurringduringactualtestoperation,wherepowertransmittedthroughthevehicletiresisdifferentfromthecoastdownconditionsoftheroadloadderivation.TABLEOFCONTENTS1.Scope.......................................................................................................................................................21.1Purpose....................................................................................................................................................22.References...............................................................................................................................................22.1ApplicablePublications.............................................................................................................................22.2RelatedPublications.................................................................................................................................23.Definitions.................................................................................................................................................34.Symbols....................................................................................................................................................55.Equipment................................................................................................................................................5SAEJ2264IssuedAPR95-2-5.1Dynamometer...........................................................................................................................................55.2RestraintSystem.......................................................................................................................................65.3AirCirculation/Cooling..............................................................................................................................66.RoadLoadDerivationProcedure..............................................................................................................76.1.Summary..................................................................................................................................................76.2RecommendedPre-testCalibrationCheck...............................................................................................76.3VehiclePreparation...................................................................................................................................76.4DynamometerSet-up................................................................................................................................76.5Vehicle