SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 1 James A. Sherwood Patrick J. Drane SGMA Meeting 04 October 2003 An Experimental Investigation of Workhardening Effect of Aluminum Bats
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 2 Introduction Effect of Use on Aluminum Baseball Bat Performance Machine testing Field hitting
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 3 Outline Background Test Methodologies Analysis Methodologies Effect of Use Results Conclusions Recommendations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 4 Outline Background Test Methodologies Analysis Methodologies Effect of Use Results Conclusions Recommendations Motivation History UMLBRC Past Research Theory
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 5 Motivation for Research Maintaining the integrity of collegiate baseball Increased interest in what drives changes in performance
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 6 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
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 7 UMLBRC Established in 1998 Research testing for MLB Official certification center for all bats used in NCAA and high school baseball
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 8 BRC Capabilities Baum Hitting Machine
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 9
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 10 UMLBRC Capabilities 3-Pt Bend Testing Modal Testing Finite Element Modeling Baseball Dissection COR Testing
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 11 Workhardening Theory Increase of Yield Strength Plastic deformation causes changes in the microstructure that leads to hardening
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 12 C405 tensile test
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 13 Terminology Bat Performance Sweet Spot Certification Cycle The Bat KnobHandleThroat / TaperBarrelTip
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 14 Outline Background Test Methodologies Analysis Methodologies Effect of Use Results Conclusions Recommendations Existing Test Methods Effect of Use
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 15 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
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 16 Outline Background Test Methodologies Analysis Methodologies Effect of Use Results Conclusions Recommendations BESR 95% confidence t-test Control Charts
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 17 BESR Conservation of Momentum & Coefficient of Restitution =BESR=ƒ(e,μ)
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 18 Outline Background Test Methodologies Analysis Methodologies Effect of Use Results Conclusions Recommendations Performance Surface Deformation Hardness Microscopy
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 19 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
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 20 PD01 Average Exit Velocity (AEV) – Sweet Spot
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 21 PD01 BESR – Sweet Spot
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 22 PD01 AEV – Average All 5 Locations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 23 PD01 BESR – Average All 5 Locations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 24 CycleProbability (%) PD01 – AEV – Sweet Spot 3 of 20
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 25 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
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 26 CycleProbability (%) PD01 – BESR – Sweet Spot 7 of 20
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 27 CycleProbability (%) PD01 – AEV – All 5 Locations 9 of 20
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 28 CycleProbability (%) PD01 – BESR – All 5 Locations 17 of 20
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 29 PD01 Lumped Analysis – Sweet Spot
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 30 PD01 Lumped Analysis – All 5 Locations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 31 PD01 Performance Summary Analysis Method Range (mph) Min (mph) Max (mph) Sweet Spot AEV0.86± Sweet Spot BESR-based AEV1.63± All Hits of Cycle AEV1.20± All Hits of Cycle BESR-based AEV1.69±
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 32 PD02 BESR – All 5 Locations Analysis MethodRange (mph)Min (mph)Max (mph) All Hits of Cycle BESR-based AEV-0.64±
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 33 PD02 Surface Deformation Measurements 5-inch 6-inch 7-inch
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 34 PD03 Sweet Spot All 5 Locations 1 of 250 of of 25 7 of 25
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 35 PD03 Lumped Analysis – Sweet Spot
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 36 PD03 Lumped Analysis – All 5 Locations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 37 PD03 Performance Summary Analysis Method Range (mph) Min (mph) Max (mph) Sweet Spot AEV0.45± Sweet Spot BESR-based AEV0.60± All Hits of Cycle AEV0.56± All Hits of Cycle BESR-based AEV0.66±
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 38 PD03 Rockwell Hardness Measurements
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 39 PD03 Vicker’s Micro-hardness Measurements
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 40 PD04 Sweet Spot5.0-, 5.5-, and 6.0-inch Locations 1 of 6 0 of 6 2 of 6 1 of 6
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 41 PD04 Lumped Analysis – Sweet Spot
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 42 PD04 Lumped Analysis – 5.0-, 5.5-, and 6.0-inch Locations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 43 PD04 Performance Summary Analysis Method Range (mph) Min (mph) Max (mph) Sweet Spot AEV0.26± Sweet Spot BESR-based AEV0.26± ,5.5-, and 6.0-inch of Cycle AEV0.34± ,5.5-, and 6.0-inch of Cycle BESR-based AEV 0.34±
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 44 PD05 Lumped Analysis – Sweet Spot
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 45 PD05 Lumped Analysis – All 6 Locations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 46 PD05 Performance Summary Analysis Method Range (mph) Min (mph) Max (mph) Sweet Spot AEV-0.36± Sweet Spot BESR-based AEV-0.58± All Hits of Cycle AEV-0.41± All Hits of Cycle BESR-based AEV-0.15±
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 47 Effect of Use Results Summary Test Range of Increase (mph) Average Increase (mph) Denting (inches) Comments PD010.7 to n/aCracking in barrel (830 hits in BHM) PD to Severe denting (147 hits in BHM) PD030.2 to Cracking in barrel (806 hits in BHM) PD to Test ended before cracking or denting PD to Test ended before cracking or denting
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 48 Outline Background Test Methodologies Analysis Methodologies Effect of Use Results Effect of Moisture Content Results Conclusions Recommendations
SGMA Meeting October Dallas, TX University of Massachusetts Lowell Baseball Research Center 49 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