1、Designation:F189011An American National StandardStandard Test Method forMeasuring Softball Bat Performance Factor1This standard is issued under the fixed designation F1890;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of l
2、ast revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers a method for determining batperformance by measuring the bat-ball coefficient of restitution(BBCOR),
3、deriving the bat performance factor(BPF)andcalculating a batted ball speed(BBS).It is applicable tosoftball bats of any construction or material.The methodprovides a quantitative measure of bat dynamic performancethat may be used for comparison purposes.1.2 The BBCOR,BPF,and BBS are each calculated
4、frommeasurements taken in the laboratory on test equipmentmeeting the requirements defined in this specification.1.3 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand a
5、re not considered standard.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory requirements pri
6、or to use.2.Referenced Documents2.1 ASTM Standards:2F1887 Test Method for Measuring the Coefficient of Resti-tution(COR)of Baseballs and SoftballsF1888 Test Method for Compression-Displacement of Base-balls and SoftballsF2398 Test Method for Measuring Moment of Inertia andCenter of Percussion of a B
7、aseball or Softball Bat3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 balance point,ndistance to the center of mass of abat when measured from the distal end of the bat knob.3.1.2 bat-ball coeffcient of restitution(BBCOR),nCORof a specific ball colliding with a bat as defined
8、in this testmethod.See coeffcient of restitution(COR).3.1.3 bat performance factor(BPF),nratio of BBCOR toball COR as defined in this test method.3.1.4 center of percussion(COP),nalso known as thecenter of oscillation,the length of a simple pendulum with thesame period as a physical pendulum,as in a
9、 bat oscillating ona pivot.Forces and impacts at this location will not induceaxial reactions at the pivot point.3.1.5 coeffcient of restitution(COR),nmeasure of impactefficiency calculated as the relative speed of the objects afterimpact divided by the relative speed of the objects beforeimpact.3.1
10、.6 moment of inertia(MOI),nmeasure of mass distri-bution relative to an axis of rotation.It is the product of themass multiplied by the square of the distance to the mass,summed over the entire bat.4.Significance and Use4.1 This test method offers a laboratory means to comparethe performance of a so
11、ftball bat.4.2 Use of this test method can provide sports governingbodies a means to compare calculated BBS and other physicalproperties of bats.5.Apparatus5.1 Test BallsOfficial softballs approved for play andtested in accordance with the following procedures.Performball compression test of Test Me
12、thod F1888 prior to ball CORtest of Test Method F1887.5.1.1 Compression350 to 375 lb at 0.25-in.deflection(1557 to 1668 N at 6.4-mm deflection)in accordance with TestMethod F1888.Balls to be labeled with compression value.5.1.2 Weight6.25 to 6.75 oz(177.2 to 191.4 g).Balls to belabeled with weight v
13、alue.5.1.3 Size12.00 to 12.25-in.(304.8 to 311.1-mm)circum-ference.Balls to be labeled with size value.5.1.4 Core MaterialPolyurethane.1This test method is under the jurisdiction of ASTM Committee F08 on SportsEquipment and Facilities and is the direct responsibility of Subcommittee F08.26 onBasebal
14、l and Softball Equipment.Current edition approved Nov.1,2011.Published November 2011.Originallyapproved in 1998.Last previous edition approved in 2009 as F1890 09.DOI:10.1520/F1890-11.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.or
15、g.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.1.5 Ball COR0.450 to 0.470 in accordance with TestMethod F1887.Balls t
16、o be labeled with COR and test speed inft/s.5.2 Bat-Ball COR Test Apparatus:5.2.1 Ball CannonA device capable of shooting a ball at aspeed of 88 ft/s.The ball shall not have a spin rate in excess of10 rpm.Typical pitching machines cannot yield the aimingaccuracy required by this test method.Cannon exhaust air mustnot cause motion of the bat in the absence of an impact.Theball cannon can be any distance from impact location,as longas it can meet the ball aim requirements and provide six validimpa
