1 / 7

Alan M. Nathan University of Illinois a-nathan@uiuc

Bat Performance and the NCAA Certification Protocol Does Aluminum Outperform Wood? Presentation made to the ASTM Subcommittee on Bats and Balls May 23, 2007. Alan M. Nathan University of Illinois a-nathan@uiuc.edu. REMINDER: Three parameters determine batted ball speed (BBS) in the field.

amina
Download Presentation

Alan M. Nathan University of Illinois a-nathan@uiuc

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Bat Performance and the NCAA Certification ProtocolDoes Aluminum Outperform Wood?Presentation made to the ASTM Subcommittee on Bats and BallsMay 23, 2007 Alan M. Nathan University of Illinois a-nathan@uiuc.edu

  2. REMINDER:Three parameters determine batted ball speed (BBS) in the field BBS = (BESR-0.5)vpitch+(BESR+0.5)vbat • measure BESR in the lab • define “standard field conditions” • --vpitch • --vbat (depends on MOI) • use these to predict BBS in the field

  3. Relation between swing speed and MOI aluminum wood

  4. BESR same BBS lower BBS higher BBS MOI The NCAA Bat Certification Process • Each bat is characterized by two regulated numbers: • BESR: performance metric for fixed bat speed • MOI: metric related to field bat speed • Together, these determine BBS Higher BESR, higher MOI  same BBS Same BESR, lower MOI  Higher BBS Same MOI, lower BESR  Lower BBS

  5. 102 mph max vf 97 mph BESR limit typical wood MOI limit Example: 34” Bats All bats below horizontal line and to right of vertical line are allowed

  6. Conclusion • The NCAA certification protocol limits field performance of non-wood bats • Under “standard” conditions--- • Wood = 97 mph • Non-wood < 102 mph • Difference < 5 mph, or about 5%

  7. Summary:The NCAA certification protocol limits field performance of non-wood bats • Does aluminum outperform wood? • YES, by about 5% • the 5% is an estimate based on the current state of the science • left unregulated, aluminum would outperform wood by a significantly greater margin

More Related