1 / 18

Physics 199BB The Physics of Baseball

Explore the physics behind baseball flight, including drag and Magnus forces, using the PITCHf/x Tracking System. Learn how to analyze pitch data freely available online and delve into topics like pitch classification and trajectory deviations. Uncover the secrets behind pitch movement and break, as well as the impact of spin on baseball trajectory. Discover how science enhances our understanding of the game.

inge
Download Presentation

Physics 199BB The Physics of Baseball

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. Week 5 1 Physics 199BB The Physics of Baseball Fall 2007 Freshman Discovery Course Alan M. Nathan 403 Loomis 333-0965 a-nathan@uiuc.edu Week 5

    2. Week 5 2 Forces on a Baseball in Flight Gravity Already discussed Drag (“air resistance”) Force Already discussed Magnus Force Already discussed

    3. Week 5 3 Review: Here are the formulas FMx = FM {sin (?)vz/v-cos(?)vy/v} FMy = FM cos (?)vx/v FMz = -FM sin(?)vx/v aMx=2.09x10-6 CM?g {sin(?)vz-cos(?)vy} aMy=2.09x10-6 CM?gcos(?)vx aMz=-2.09x10-6 CM?gsin(?)vx

    4. Week 5 4 The PITCHf/x Tracking System MLB Gameday

    5. Week 5 5 How Does PITCHf/x Work? Two video cameras track baseball in 1/60-sec intervals usually “high home” and “high first” third CF camera used establises ht. of strike zone for each batter Pattern-recognition software to identify “blobs” Camera calibration to convert pixels to (x,y,z) 9-parameter fit to trajectory constant acceleration for x(t),y(t),z(t) Use fit to calculate lots of stuff

    6. Week 5 6 Example: Bond’s 756th home run

    7. Week 5 7 What kind of “stuff”? Pitch speed at release Pitch speed at home plate (~10% less) Location of pitch as it crosses home plate “break” of pitch—deviation from straight-line trajectory Release point of pitch ball Initial velocity direction

    8. Week 5 8 And the good news is…. …all these data are freely available online! to learn how to do it, see http://webusers.npl.uiuc.edu/~a-nathan/pob/pitchtracker.html Example: Jon Lester (Red Sox) vs. Seattle, Aug. 3, 2007

    9. Week 5 9 “movement” vs. “break”

    10. Week 5 10 pfx_x and pfx_z (“movement”) Deviation of trajectory due to spin of baseball Calculated by setting ax=0 (no sideways acceleration) az = -g (vertical acceleration only from gravity) calculate location of ball as it crosses home plate compare with actual location pfx_x, pfx_z = actual-calculated pfx=sqrt(pfx_x2 + pfx_z2)—reported on Gameday screen

    11. Week 5 11 “break” vs. “movement” Fastball with lots of backspin has lots of “movement” but little “break” Any ball dropping more than a fastball has more vertical “break” Baseball people prefer “break” to “movement” Physicists prefer “movement”

    12. Week 5 12

    13. Week 5 13 Using PITCHf/x to obtain drag and Magnus forces

    14. Week 5 14 Pitch Classification

    15. Week 5 15 Pitch Classification

    16. Week 5 16 Pitch Classification

    17. Week 5 17 New Topic: Discussion of the “Chemical Bonds” Paper

    18. Week 5 18 Topics for Next Time (Adair, Chapter 4) Knuckleball and scuff balls Gyroballs

More Related