Designation:F2398−11(Reapproved2015)AnAmericanNationalStandardStandardTestMethodforMeasuringMomentofInertiaandCenterofPercussionofaBaseballorSoftballBat1ThisstandardisissuedunderthefixeddesignationF2398;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Methodfordeterminingthemomentofinertia(MOI),thecenterofpercussion(COP),andthebalancepoint(BP)ofbaseballandsoftballbats.ThesephysicalpropertiesareusedinTestMethodF1881,TestMethodF1890,andTestMethodsF2219.1.2TheMOI,COP,andBParemeasuredinthelaboratoryontestequipmentmeetingtherequirementsdefinedinthistestmethod.1.3Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2F1881TestMethodforMeasuringBaseballBatPerfor-manceFactor(Withdrawn2014)3F1890TestMethodforMeasuringSoftballBatPerformanceFactorF2219TestMethodsforMeasuringHigh-SpeedBatPerfor-mance3.Terminology3.1DefinitionsofTermsSpecifictoThisStandard:3.1.1balancepoint(BP),n—thedistancetothecenterofmassmeasuredfromtheknobendofthebat.3.1.2centerofpercussion(COP),n—alsoknownasthecenterofoscillation.Forcesandimpactsatthislocationwillnotinducereactionsatthepivotpoint,6in.(152mm)fromtheknobendofthebat.3.1.3cycle,n—onecompleteoscillationofapendulumsupportedatthepivotpoint,6in.(152mm)fromtheknobendofthebat.3.1.4momentofinertia(MOI),n—alsoknownasthemassmomentofinertia,themeasureofthebat’sresistancetochangesinitsrotationrateaboutthepivotpoint,6in.(152mm)fromthe...
