sgma meeting -- 04 october 2003 -- dallas, tx university of massachusetts lowell baseball research...

SGMA Meeting -- 04 October 2003 -- Dallas, TXUniversity of Massachusetts LowellBaseball Research Center 1

James A. SherwoodPatrick J. Drane

SGMA Meeting 04 October 2003

An Experimental Investigation of Workhardening Effect of Aluminum Bats


Introduction

Effect of Use on Aluminum Baseball Bat Performance

• Machine testing

• Field hitting


Outline

• Background

• Test Methodologies

• Analysis Methodologies

• Effect of Use Results

• Conclusions

• Recommendations


Outline

• Background• Test Methodologies• Analysis Methodologies• Effect of Use Results• Conclusions• Recommendations

•Motivation•History•UMLBRC•Past Research•Theory


Motivation for Research

• Maintaining the integrity of collegiate baseball

• Increased interest in what drives changes in performance


Effect of Use

• Aluminum bats can be used for a long period of time

• Aluminum bats are certified for the NCAA with a performance limit– Concern: An increase in performance resulting

from use of a bat could cause certified bat to exceed limit


UMLBRC

• Established in 1998

• Research testing for MLB

• Official certification center for all bats used in NCAA and high school baseball


BRC Capabilities Baum Hitting Machine


UMLBRC Capabilities• 3-Pt Bend Testing • Modal Testing

• Finite Element Modeling

• Baseball Dissection

• COR Testing


Workhardening Theory

• Increase of Yield Strength

• Plastic deformation causes changes in the microstructure that leads to hardening


C405 tensile test


Terminology

• Bat Performance

• Sweet Spot

• Certification Cycle

• The Bat Knob Handle Throat / Taper Barrel Tip


Outline

• Background




• Conclusions

• Recommendations

•Existing Test Methods

•Effect of Use


Effect of Use – Test Method

• Performance Testing in the Hitting Machine– All-in-Machine / Field Use with Testing

• NCAA certification testing procedure

• Same 5 locations impacted each time

• Use of official NCAA baseballs

• Complete after significant cracking or denting


Outline

• Background




• Conclusions

• Recommendations

•BESR•95% confidence•t-test•Control Charts


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vVv

BESR

2

)375.5(

)375.11(

Ll

lVV C

BESRConservation of Momentum

&Coefficient of Restitution

btb ve

Ve

v

11

1

btb vVv 2

12

1

)1(2

21

e

=BESR=ƒ(e,μ)

)( tbtb VveVv

bbttbbtt vmVMvmVM


Outline

• Background




• Conclusions

• Recommendations

•Performance•Surface Deformation•Hardness•Microscopy


Effect of Use Test Bats

PD01(Trial Test)•Performance

PD02•Performance•Surface Deformation•Hardness

PD03•Performance•Surface Deformation•Hardness•Microscopy

PD04•Performance•Surface Deformation

PD05•Performance•Surface Deformation

All-in-Machine

Field-Use


PD01Average Exit Velocity (AEV) – Sweet Spot

0 2 0 0 4 0 0 6 0 0 8 0 0 1 0 0 0N u m b er o f H its o n B at

9 4

9 5

9 6

9 7

9 8

9 9

Bat

ted-

ball

Vel

ocity

(m

ph)


9 4

9 5

9 6

9 7

9 8

9 9

Bat

ted-

ball

Vel

ocity

(m

ph)


PD01


9 4

9 5

9 6

9 7

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

BE

SR

BESR – Sweet Spot

vV

vVv

BESR

2


PD01


9 3

9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

B a tte d -b a ll V e lo c ity (R a w D a ta )

B a ll C e rtif ic a tio n (B a se lin e )


9 3

9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph) B a tte d -b a ll V e lo c ity

B a ll C e rtif ic a tio n (B a se lin e )

AEV – Average All 5 Locations


PD01


9 2

9 3

9 4

9 5

9 6

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .6 9 5

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

BE

SR

BESR – Average All 5 Locations


Cycle Probability (%)

2 95.0

3 46.0

4 67.6

5 0.7

6 73.0

7 55.4

8 13.5

9 11.4

10 29.6

11 82.2

12 10.0

13 0.4

14 44.7

15 26.3

16 47.5

17 1.2

18 87.8

19 6.2

20 44.3

21 43.7

PD01 – AEV – Sweet Spot


9 2

9 3

9 4

9 5

9 6

9 7

9 8

Bat

ted-

ball

Vel

ocity

(m

ph)

3 of 20


Confidence Intervals

• Statistical tool for evaluating magnitude of confidence in test average

• Helps to predicts likelihood of samples being from the same population

• 95% Confidence used



2 94.1

3 92.4

4 45.8

5 0.1

6 12.0

7 16.7

8 13.9

9 1.4

10 11.1

11 32.1

12 5.3

13 0.002

14 13.2

15 2.2

16 29.0

17 0.5

18 9.7

19 2.9

20 0.6

21 20.1

PD01 – BESR – Sweet Spot


9 2

9 3

9 4

9 5

9 6

9 7

9 8

9 9

Bat

ted-

ball

Vel

ocity

(m

ph)

0 .6 9 5

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

0 .7 4 0

BE

SR

7 of 20



2 93.3

3 98.2

4 25.3

5 1.3

6 15.0

7 13.3

8 4.0

9 0.3

10 2.5

11 6.7

12 0.8

13 2.6

14 6.7

15 3.6

16 2.5

17 0.8

18 20.6

19 1.0

20 3.8

21 1.7

PD01 – AEV – All 5 Locations


9 2

9 3

9 4

9 5

9 6

Bat

ted-

ball

Vel

ocity

(m

ph)

9 of 20



2 90.8

3 70.2

4 1.2

5 0.02

6 1.2

7 2.0

8 3.0

9 0.07

10 0.1

11 1.1

12 0.05

13 0.3

14 0.7

15 0.3

16 0.1

17 0.03

18 0.9

19 0.5

20 0.1

21 0.5

PD01 – BESR – All 5 Locations


9 2

9 3

9 4

9 5

9 6

9 7

Bat

ted-

ball

Vel

ocity

(m

ph)

0 .6 9 5

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

BE

SR

17 of 20


PD01


9 3

9 4

9 5

9 6

9 7

Bat

ted-

ball

Vel

ocity

(m

ph)

Lumped Analysis – Sweet Spot


9 3

9 4

9 5

9 6

9 7

Bat

ted-

ball

Vel

ocity

(m

ph)

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

BE

SR


PD01


9 2

9 3

9 4

9 5

9 6

Bat

ted-

ball

Vel

ocity

(m

ph)

Lumped Analysis – All 5 Locations


9 2

9 3

9 4

9 5

9 6

Bat

ted-

ball

Vel

ocity

(m

ph)

0 .6 9 5

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

BE

SR


PD01

Performance Summary

Analysis MethodRange(mph)

Min(mph)

Max(mph)

Sweet Spot AEV 0.86±0.88 -0.02 1.74

Sweet Spot BESR-based AEV 1.63±0.97 0.66 2.60

All Hits of Cycle AEV 1.20±0.95 0.25 2.15

All Hits of Cycle BESR-based AEV 1.69±0.98 0.71 2.67


PD02BESR – All 5 Locations

Analysis Method Range (mph) Min (mph) Max (mph)

All Hits of Cycle BESR-based AEV -0.64±1.12 -1.76 0.48


9 2

9 3

9 4

9 5

9 6

9 7

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .6 9 5

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

BE

SR


PD02

0

45

90

135

180

225

270

315

0 0.4 0.8 1.2

0

45

90

135

180

225

270

315

0 0.4 0.8 1.2

Surface Deformation Measurements

0

45

90

135

180

225

270

315

0 0.4 0.8 1.2

5-inch 6-inch 7-inch


PD03


9 3

9 4

9 5

9 6

9 7

9 8

9 9

1 0 0

1 0 1B

atte

d-B

all V

eloc

ity (

mph

)


9 3

9 4

9 5

9 6

9 7

9 8

9 9

1 0 0

1 0 1

1 0 2

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 0 00 .7 0 50 .7 1 00 .7 1 50 .7 2 00 .7 2 50 .7 3 00 .7 3 50 .7 4 00 .7 4 50 .7 5 00 .7 5 50 .7 6 0

BE

SR


9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

Sweet Spot All 5 Locations

1 of 25

0 of 250 2 0 0 4 0 0 6 0 0 8 0 0 1 0 0 0

N u m b er o f H its o n B at

9 3

9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

BE

SR

13 of 25

7 of 25


PD03


9 5

9 6

9 7

9 8

9 9

Bat

ted-

Bal

l Vel

ocity

(m

ph)



9 5

9 6

9 7

9 8

9 9

1 0 0

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

0 .7 4 0

0 .7 4 5

0 .7 5 0

BE

SR


PD03


9 4

9 5

9 6

9 7

Bat

ted-

Bal

l Vel

ocity

(m

ph)



9 4

9 5

9 6

9 7

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

BE

SR


PD03

Performance Summary


Min(mph)

Max(mph)

Sweet Spot AEV 0.45±0.81 -0.36 1.26

Sweet Spot BESR-based AEV 0.60±0.93 -0.33 1.53

All Hits of Cycle AEV 0.56±0.43 0.13 0.99

All Hits of Cycle BESR-based AEV 0.66±0.45 0.21 1.11


PD03Rockwell Hardness Measurements

0 2 0 0 4 0 0 6 0 0N u m b er o f H its o n B at

9 0

9 1

9 2

9 3

9 4

9 5

Roc

kwel

l Har

dnes

s N

umbe

r (B

-Sca

le)


PD03Vicker’s Micro-hardness Measurements

6 -in ch 4 .5 -in ch 2 -in ch

P o s itio n o f T es ts fro m B arrel E n d o f B at

1 8 0

1 8 5

1 9 0

1 9 5

2 0 0

2 0 5

Vic

kers

Har

dnes

s N

umbe

r


PD04

0 4 0 0 8 0 0 1 2 0 0 1 6 0 0N u m b er o f H its o n B at

9 4

9 5

9 6

9 7

9 8

9 9B

atte

d-B

all V

eloc

ity (

mph

)


9 4

9 5

9 6

9 7

9 8

9 9

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

0 .7 4 0

BE

SR


9 4

9 5

9 6

9 7

9 8

9 9

Bat

ted-

Bal

l Vel

ocity

(m

ph)

Sweet Spot 5.0-, 5.5-, and 6.0-inch Locations

1 of 6

0 of 6 2 of 6


9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

BE

SR

1 of 6


PD04


9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)



9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

BE

SR


PD04


9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

Lumped Analysis – 5.0-, 5.5-, and 6.0-inch Locations


9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

0 .7 3 0

0 .7 3 5

BE

SR


PD04

Performance Summary


Min(mph)

Max(mph)

Sweet Spot AEV 0.26±0.78 -0.52 1.04

Sweet Spot BESR-based AEV 0.26±0.86 -0.60 1.12

5.0-,5.5-, and 6.0-inch of Cycle AEV 0.34±0.59 -0.25 0.93

5.0-,5.5-, and 6.0-inch of Cycle BESR-based AEV

0.34±0.55 -0.21 0.89


PD05

In itia lA fte r 2 ½ m o n th s

T im e o f T es tin g

9 3

9 4

9 5

9 6

9 7

9 8

Bat

ted-

Bal

l Vel

ocity

(m

ph)




9 3

9 4

9 5

9 6

9 7

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

0 .7 2 5

BE

SR


PD05



9 2

9 3

9 4

9 5

9 6

Bat

ted-

Bal

l Vel

ocity

(m

ph)




9 2

9 3

9 4

9 5

9 6

Bat

ted-

Bal

l Vel

ocity

(m

ph)

0 .6 9 5

0 .7 0 0

0 .7 0 5

0 .7 1 0

0 .7 1 5

0 .7 2 0

BE

SR


PD05

Performance Summary


Min(mph)

Max(mph)

Sweet Spot AEV -0.36±1.88 -2.24 1.52

Sweet Spot BESR-based AEV -0.58±1.90 -2.48 1.32

All Hits of Cycle AEV -0.41±1.22 -1.63 0.81

All Hits of Cycle BESR-based AEV -0.15±1.26 -1.41 1.11


Effect of Use Results Summary

TestRange ofIncrease

(mph)

AverageIncrease

(mph)

Denting(inches)

Comments

PD01 0.7 to 1.7 1.3 n/a Cracking in barrel (830 hits in BHM)

PD02 -1.8 to 0.5 -0.6 0.0405 Severe denting (147 hits in BHM)

PD03 0.2 to 1.0 0.6 0.0053 Cracking in barrel (806 hits in BHM)

PD04 -0.2 to 0.9 0.3 0.0084 Test ended before cracking or denting

PD05 -1.4 to 0.8 -0.4 0.0072 Test ended before cracking or denting


Outline

• Background




• Effect of Moisture Content Results

• Conclusions

• Recommendations


Conclusion

• The result of using an aluminum baseball bat may lead to a slight increase in batted-ball performance

• Increase is probably a result of softening of the aluminum – due to increased contact time

sgma meeting -- 04 october 2003 -- dallas, tx university of massachusetts lowell baseball research...

Documents

research theory slide

research testing

drane sgma meeting

performance slide

high school baseball

machine slide

limit slide

hardening slide