ASTM F2219-2009 Standard Test Methods for Measuring High-Speed Bat Performance.pdf

1、Designation: F 2219 09An American National StandardStandard Test Methods forMeasuring High-Speed Bat Performance1This standard is issued under the fixed designation F 2219; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year o

2、f last 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 These test methods define a method for determining batperformance by measuring the bat-ball coefficient of restituti

3、on(BBCOR), deriving the ball exit speed ratio (BESR), andcalculating a batted-ball speed (BBS). It is applicable tobaseball and softball bats of any construction or material. Thetest methods provide quantitative measures of bat dynamicperformance that may be used for comparison purposes.1.2 The BBCO

4、R, BESR, and BBS are each calculated 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

5、are provided for information onlyand are 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 to determine theap

6、plicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2F 1887 Test Method for Measuring the Coefficient of Res-titution (COR) of Baseballs and SoftballsF 1888 Test Method for Compression-Displacement ofBaseballs and SoftballsF 2398 Test Method for Measuring Mom

7、ent of Inertia andCenter of Percussion of a Baseball or Softball Bat3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 balance point (BP), ndistance to the center of massof a bat when measured from the distal end of the bat knob.3.1.2 ball exit speed (Vf), noutbound speed of a ba

8、llfollowing impact with a bat as defined in these test methods.3.1.3 ball exit speed ratio (BESR), nratio of ball exitspeed (vr) to ball inbound speed (vi) plus12 , as determined bythese test methods.3.1.4 ball inbound speed (vi), ninbound speed of a ballprior to impact with a bat as defined in this

9、 test method.3.1.5 bat-ball coeffcient of restitution (BBCOR)COR of aspecific ball colliding with a bat as defined in these testmethods. See coeffcient of restitution (COR).3.1.6 center of percussion (COP), nalso known as thecenter of oscillation, the length of a simple pendulum with thesame period

10、as a physical pendulum, as in a bat oscillating ona pivot.3.1.7 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.3.1.8 moment of inertia (MOI), nmeasure of mass distri-b

11、ution 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 These test methods offer a laboratory measure of theperformance of baseball and softball bats.4.2 Use of these test methods c

12、an provide quantitativebatted-ball speed and metrics of bat performance.5. Apparatus and Equipment5.1 Test BallsOfficial baseballs and softballs approved foruse in the game of baseball or softball and tested in accordancewith Table 1.1These test methods are under the jurisdiction of ASTM Committee F

13、08 onSports Equipment and Facilities and are the direct responsibility of SubcommitteeF08.26 on Baseball and Softball Equipment.Current edition approved June 1, 2009. Published July 2009. Originally approvedin 2002. Last previous edition approved in 2007 as F 2219 07.2For referenced ASTM standards,

14、visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.TABLE 1 Ball SpecificationsOption 1SoftballOption 2BaseballCompressionper F 1888350375 lb 250

15、300 lb15571668 N 11121335 NWeight 6.757.00 oz 5.095.16 oz191198 g 144147 gCircumference 12.0012.25 in. 9.009.25 in.304.8311.1 mm 228234 mmCORper F 18870.4300.440 0.5250.5551Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Balls spe

16、cification values are to be recorded and tracedto individual balls.5.3 Bat-Ball COR Test Apparatus:5.3.1 Ball CannonA device capable of shooting a softballat speeds at least up to 205.3 ft/s (62.6 m/s, approximately 140mph) for Option 1 or a baseball at speeds at least up to 220 ft/s(67.1 m/s, appro

17、ximately 150 mph) for Option 2, or both. Ballsshall be oriented to impact the strike surface between thestitches. Typical pitching machines cannot yield the aimingaccuracy required by these test methods. Cannon exhaust airmust not cause motion of the bat in the absence of an impact.5.3.2 Ball Speed

18、GateA light trap device, or an equiva-lent, capable of measuring a softball traveling at speeds at leastup to 205.3 ft/s (62.6 m/s, approximately 140 mph) for Option1 or a baseball traveling at speeds at least up to 220 ft/s (67.1m/s, approximately 150 mph) for Option 2, or both, with anaccuracy of

19、63 ft/s (0.89 m/s) or better. The device shallmeasure across a length of no less than half the ball diameterto avoid centering error. For example, the device shall sense anobject across a 2.0 in. (50.8 mm) line. The first sensor shalltrigger when the ball is no more than 18.0 in. (457.2 mm) fromthe

20、bat surface. The second sensor shall trigger between 12 60.03 in. (30 6 0.08 cm) from the first sensor. The secondsensor is located between the first sensor and the bat surface.The distance between sensors must be measured and main-tained within 60.005 in. (60.13 mm) (see Fig. 1). The devicemust be

21、able to measure the ball exit speed. This requirementdictates that the device must reset and arm quickly enough tocapture the ball traveling back through the speed gate.5.3.3 Bat Pivot SupportA turntable, rotating in the hori-zontal plane, with clamps to support and align the bat in thepath of the b

22、all. The clamp surfaces shall be a 45 Vee clampwith no radii greater than 2.0 in. (50.8 mm). The rotating clampand shaft assembly shall not weigh more than 6 lb (2.7 kg) andshall spin freely via ball bearings (see Fig. 1). The actual MOIof the clamp turntable assembly shall be determined, recorded,a

23、nd used in the performance calculations. The polar MOI forthe clamp turntable assembly shall not exceed 192 oz-in.2(35117 g-cm2).6. Calibration and Standardization6.1 Ball Speed GateThe distances between the sensors ofthe speed gates must be known and recorded to the statedtolerances. The accuracy o

24、f the timers used in the velocitysensors must be adequate to provide the stated velocityaccuracy at maximum stated speeds. The timers used shall becalibrated on at least a yearly basis.6.2 Reference Standards and BlanksA standard bat andball shall be used for reference purposes to verify propermachi

25、ne operation.7. Conditioning7.1 Ball and Bat Conditioning and Test Room Conditions:7.1.1 Test balls shall be stored in an environmentallycontrolled space for at least 14 days immediately beforetesting. Wood bats shall be stored at these environmentalconditions for at least 24 h prior to testing. Non

26、-wood batsshall be stored at these test environmental conditions for atleast 2 h prior to testing.7.1.2 Temperature is to be maintained at 72 6 4F (22 62C).7.1.3 Relative humidity is to be maintained between 40 and60 %.7.1.4 Temperature and relative humidity are to be measuredand recorded hourly wit

27、hin 60.5F (60.3C) and 62%RHover conditioning and test duration.8. Procedure8.1 Determination of Bat Features and Test LocationDetermine bat balance point (BP), bat MOI, and bat COP inaccordance with Test Method F 2398.8.2 Impact LocationsThree methods for testing are de-scribed herein for evaluating

28、 the performance of a bat. Thesemethodologies provide alternatives for determining the impactlocation of the bat-ball collision prescribed by these testmethods.8.2.1 Method AImpact location is 6 in. from the barrelend of the bat.8.2.2 Method BImpact location is at the COP.8.2.3 Method CMultiple impa

29、ct locations for identifyingthe maximum value of the performance variable in question.FIG. 1 Bat Testing MachineF22190928.2.3.1 Select a performance variable (BBCOR, BESR, orBBS) to calculate. The choice of performance variable is left tothose specifying the test requirements.8.2.3.2 Test at an init

30、ial impact location 5.0, 6.0, or 7.0 in.(127, 152.4, or 177.8 mm) from the barrel end of the bat.Repeat testing at 1.0-in. (25.4-mm) intervals in either directionfrom the initial impact location until a local maximum is found,then converge on the maximum performance location in 0.5-in.(12.7-mm) incr

31、ements.8.2.3.3 The maximum value to the nearest 0.5-in. (12.7-mm) interval is the impact location to be used under Method C(that is, if local maxima are found at 4.0 in. (101.6 mm) and 5.0in. (127.0 mm), the test is then done at 4.5 in. (114.3 mm). Themax performance location is the one associated w

32、ith themaximum of the test results obtained from these three impactlocations of 4.0 in. (101.6 mm), 4.5 in. (114.3 mm), and 5.0 in.(127.0 mm).8.3 Bat Test Procedure:8.3.1 Ready and calibrate ball speed gates in accordancewith the manufacturers instructions.8.3.2 Select six test balls meeting require

33、ment of 5.1, andrecord the actual values of compression, weight, size, and CORof the ball.8.3.3 Set ball cannon to fire the ball per Table 1 at thedesired impact speed as noted in Table 2 for Option 1 (softball)and Eq 1 for Option 2 which determines the nominal impactspeed which varies with the desi

34、red impact point selected inaccordance with 8.2. Valid test speeds are considered to bethose within tolerance noted in Table 2 and Eq 1.vi5 66 6 2 mph 3L 2 X 2 6 in.!L 2 12 in.!1 70 mph (1)vi5 96.8 6 3 ft/s 3L 2 X 2 6 in.!L 2 12 in.!1 102.6 ft/svi5 29.5 6 0.9 m/s 3L mm! 2 X mm! 2 152.4 mm!L mm! 2 30

35、4.8 mm!1 31.3 m/swhere:L = length of bat, in. (mm),X = distance from the end of the barrel to the impactlocation, in. (mm), andvi= ball inbound speed, mph, ft/s (m/s).8.3.4 Mount the bat in the clamps on the bat pivot support.Position the distal end of the bat knob 6 6 0.063 in. (152.4 61.6 mm) from

36、 the axis of rotation of the turntable assembly.8.3.5 The ball impact must be centered vertically andhorizontally on the bat diameter at the desired impact locationin accordance with 8.2.8.3.6 Position the bat against the start position reference,which must place the bat axis perpendicular to the ba

37、ll line oftravel (see Fig. 1).8.3.7 Verify that all ball speed gates are reset and ready totake data.8.3.8 Load selected test ball in ball cannon. Load test ball sothat its impact with the bat will occur between the stitches ofthe ball.8.3.9 Shoot the ball at the bat, observing the necessarysafety p

38、recautions.8.3.10 Verify proper bat alignment by observing the re-bound path of the ball after impact with the bat. The ball shouldrebound directly back toward the cannon, retracing its impacttrajectory within 65.8.3.11 Record ball inbound speed and ball exit speed. Donot use data where the ball inb

39、ound speed deviates by morethan the tolerances and speeds defined in 8.3.3 and Table 2.8.3.12 Continue testing for six valid readings per location.For a given test ball, rotate the ball in the cannon betweenimpacts so that the impact area of the ball is different for eachimpact. If six valid impacts

40、 are not achieved prior to twelvetotal impacts, fix setup to alleviate cause of invalid impacts.Verify that support system for ball cannon, ball speed gate, andbat pivot support are rigid.8.3.13 Balls are retired per Table 3.9. Calculation of Results9.1 Calculate the bat-ball coefficient of restitut

41、ion (BBCOR)for each valid impact using Eq 2 and Eq 3:BBCOR 5vi1 vrvi$m / Me1 1% 1 (2)TABLE 2 Ball Incoming Speeds and Bat Mounting LocationsOption 1SoftballOption 2BaseballSpeedVariationsSpeed is constantall locationsSpeed varies with impactlocation. See Eq 1.Speed shown here is forimpacts 6 in. (15

42、2 mm)from barrel end of the bat.BallSpeed110 6 1 mph 136 6 2 mph161.3 6 1.61 ft/s 199.5 6 3 ft/s49.1 6 0.49 m/s 60.8 6 0.89 m/sDistalLocationto PivotLocation6in. 6in.152.4 mm 152.4 mmTABLE 3 Ball Retirement and ReuseOption 1SoftballOption 2BaseballStop testing after 40 total hits. Retire ball after

43、2 hits eachpanel (ear) which is a totalof 8 hits per ball.Retest ball compression perF 1888. If ball compression isless than original ballcompression value, retire theball, otherwise put ball backinto service for an additional 40hits.A single test ball may be testedonce on each impact area of thebal

44、l with no rest period betweenimpacts. Following this seriesof up to four impacts on asingle ball, a rest period of atleast 10 min following the lastimpact is required prior toretesting using the same testball.Rest baseball at least 16 hbefore using again in the test.F2219093Me5I 1 IpivotQ2(3)where:Q

45、 = distance from the impact location and pivot pointlocation, in. (cm),Me= effective bat mass, oz (g),I = moment of inertia (MOI) of bat, oz-in.2(g-cm2),Ipivot= moment of inertia of pivot stage, oz-in.2(g-cm2),vi= ball inbound speed, in./s (cm/s),vr= ball rebound speed, in./s (cm/s), andm = weight o

46、f ball used in each impact, oz (g).9.2 Calculate the ball exit speed ratio (BESR) of the test batnormalized to a nominal ball of mass, m0, which must besupplied by the group or individual seeking to calculate BESR,using Eq 4, where symbols are defined in Eq 2:BESR 5BBCOR m0/ Me1 1 m0/ Me1 0.5 (4)whe

47、re:m0= nominal weight of ball specified by user or group, oz(g).9.3 Calculate the average BESR for the test bat from the sixvalid impacts using Eq 5:BESRavg5BESR!11BESR!21 . 1BESR!66(5)9.4 Calculate the batted-ball speed (BBS) value of the testbat using Eq 6:BBS 5 v BESR 2 0.5! 1 V BESR 1 0.5! (6)wh

48、ere:V = bat swing speed (mph) at the point of impact, whichmust be supplied by the individual or group seeking tocalculate BBS, andv = ball pitch speed (mph), which must be supplied by theindividual or group seeking to calculate BBS.9.5 Calculate the average batted ball speed (BBS) value ofthe test

49、bat from the six valid impacts using Eq 7:BBSavg5BBS!11 BBS!21 . 1 BBS!66(7)10. Report10.1 Report the following information:10.1.1 Name of the test facility and test operator,10.1.2 Test date,10.1.3 Hourly measurements of test conditions, including:10.1.3.1 Relative humidity and temperature of the ball andbat conditioning and test room environments,10.1.3.2 Number of hours ball and bat were in conditioningenvironment.10.1.4 Test equipment used for this test method,10.1.5 Test ball information in acc