If you watched the recent Home-Run Derby on ESPN, you might have noticed that the balls were tracked mid-flight with a colored “comet trail”. Popular Science has an article talked to the german firm “Trackman” who built the technology making it possible.
The Ball Tracker utilizes low-power Doppler radar operating at 2000 Hz to monitor the speed, location and spin of the ball. That data is fed to an algorithm which calculates the projected path of the ball based on its current location. This allows ESPN to continuously display the distance traveled on the screen during flight and to calculate the total home run length as soon as the ball lands (previous methods took seconds or minutes to get the same information).
See a video of the effect after the break.
via How It Works: ESPN’s Ball Tracker Follows Home Runs With Doppler Radar | Popular Science.
