1 / 12

Tracking the Baseball with the TrackMan Doppler Radar

Tracking the Baseball with the TrackMan Doppler Radar. Busch. Petco. A Brief Introduction. The Doppler Technique. Doppler Frequency Shift. f D = Doppler Shift = F TX - F RX =  2F TX (V R /c). V R = dr/dt = rate of change of distance of ball from TM. Batted ball. Bat. Bounce.

arvid
Download Presentation

Tracking the Baseball with the TrackMan Doppler Radar

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. Tracking the Baseball with the TrackMan Doppler Radar Busch Petco A Brief Introduction

  2. The Doppler Technique Doppler Frequency Shift fD = Doppler Shift = FTX - FRX = 2FTX(VR/c) VR= dr/dt = rate of change of distance of ball from TM

  3. Batted ball Bat Bounce Pitched ball Frequency/Velocity vs. Time Doppler shift Radial velocity Time 

  4. Slightly More Detail • Want to determine location of baseball as function of time • TM determines r,, • r = distance from TM • ,=orientation angles wrt TM

  5. Summary of TM Technique: r,, • Determining r(t) • Doppler shift determines dr/dt • Two-frequency phase shift determines r(0)

  6. Determining r(0) • Transmit two wavelengths 1 and 2 • Initially in phase • After reflection and detection, out of phase by 2r(1/ 1 - 1/ 2) • Measuring phase shift at t=0 determines r(0)

  7. Measuring angles Phase Shift Between Detectors Angles Extra distance = Dsin()  phase shift

  8. Three Detectors  ,

  9. Summary of Technique • Doppler shift determines dr/dt • Two wavelength phase shift determines r(0) • r(0) + dr/dt  r(t) • 3-detector array phase shifts determine (t), (t) • r(t), (t), (t) gives full 3D trajectory • Need to convert to field coordinates using location and orientation of TM

  10. Measurement Principle: Spin Doppler frequency modulated by rotation frequency  Sidebands separated by n

  11. TrackMan Capabilities I:Full pitched ball trajectory • Everything PITCHf/x gives plus…. • Actual release point (“extension”)  perceived velocity • Total spin (including “gyro” component) • Many more points on the trajectory Utility of more points under study

  12. TrackMan Capabilities II:Full batted ball trajectory • Batted ball speed, launch & spray angles Equivalent to HITf/x • Landing point coordinates at ground level and hang time Equivalent to Hittracker • Initial spin • and more, if you want it

More Related