Posted on 01/22/2010 3:20:48 AM PST by Pharmboy
Virtual-reality baseballs give researchers insight into long-standing mystery
Rockville, MD — While baseball fans still rank "The Catch" by Willie Mays in the 1954 World Series as one of the greatest baseball moments of all times, scientists see the feat as more of a puzzle: How does an outfielder get to the right place at the right time to catch a fly ball?
Thousands of fans (and hundreds of thousands of YouTube viewers) saw Mays turn his back on a fly ball, race to the center field fence and catch the ball over his shoulder, seemingly a precise prediction of a fly ball's path that led his team to victory. According to a recent article in the Journal of Vision ("Catching Flyballs in Virtual Reality: A Critical Test of the Outfielder Problem"), the "outfielder problem" represents the definitive question of visual-motor control. How does the brain use visual information to guide action?
To test three theories that might explain an outfielder's ability to catch a fly ball, researcher Philip Fink, PhD, from Massey University in New Zealand and Patrick Foo, PhD, from the University of North Carolina at Ashville programmed Brown University's virtual reality lab, the VENLab, to produce realistic balls and simulate catches. The team then lobbed virtual fly balls to a dozen experienced ball players.
"The three existing theories all predict the same thing: successful catches with very similar behavior," said Brown researcher William Warren, PhD. "We realized that we could pull them apart by using virtual reality to create physically impossible fly ball trajectories."
Warren said their results support the idea that the ball players do not necessarily predict a ball's landing point based on the first part of its flight, a theory described as trajectory prediction. "Rather than predicting the landing point, the fielder might continuously track the visual motion of the ball, letting it lead him to the right place at the right time," Warren said.
Because the researchers were able to use the virtual reality lab to perturb the balls' vertical motion in ways that would not happen in reality, they were able to isolate different characteristics of each theory. The subjects tended to adjust their forward-backward movements depending on the perceived elevation angle of the incoming ball, and separately move from side to side to keep the ball at a constant bearing, consistent with the theory of optical acceleration cancellation (OAC). The third theory, linear optical trajectory (LOT), predicted that the outfielder will run in a direction that makes the visual image of the ball appear to travel in a straight line, adjusting both forward-backward and side-to-side movements together.
Fink said these results focus on the visual information a ball player receives, and that future studies could bring in other variables, such as the effect of the batter's movements or sound.
"As a first step we chose to concentrate on what seemed likely to be the most important factor," Fink said. "Fielders might also use information such as the batter's swing or the sound of the bat hitting the ball to help guide their movements."
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The Association for Research in Vision and Ophthalmology (ARVO) is the largest eye and vision research organization in the world. Members include more than 12,500 eye and vision researchers from over 80 countries. ARVO encourages and assists research, training, publication and knowledge-sharing in vision and ophthalmology.
ARVO's Journal of Vision (www.journalofvision.org) is an online-only, peer-reviewed, open-access publication devoted to visual function in humans and animals. It explores topics such as spatial vision, perception, low vision, color vision and more, spanning the fields of neuroscience, psychology and psychophysics. JOV is known for hands-on datasets and models that users can manipulate online.
Whenever the bat hits the ball you react with some motion NO MATTER where it is going. Takes a split second to put things together and react to the actual trajectory.
Strangely enough, it’s important to me to know whether a fielder predicts the final point based on a tracjectory predicted from early clues (as several players believe), or predicts moment-to-moment during the flight.
My next question is how long (or short) are the “moments.”
This is interesting. Thanks.
Since some of us see age 50 way back in the rear view mirror...it just now takes a bit bigger “split” in the “second” to respond. :)
You are most welcome. An interesting question in physics and human visuo-spatial physiology.
ping
This is basically what one has to do when playing tennis. You have to be able to calculate in your head where the ball is going to land in your court and then to be there when it does, and many factors go into the calculation ... where your opponent is standing, how hard he hit the ball, the angle of his racquet when he hit, and more. A “lob” is especially like a fly ball.
I believe Mays was about 430 feet from home plate when he made that catch. Parts of the Polo Grounds were around 460 feet from home plate. A truly massive outfield.
Today “The Catch” would have been a tremendous home run.
Dimensions of the Polo Grounds.
Left Field - 279 ft (85 m)
Left-Center - 450 ft (137 m)
Center Field - 483 ft (147 m)
Right-Center - 449 ft (136 m)
Right Field - 258 ft (78 m)
Specifically, Castillo and Murphy.
There’s a former Marine fighter pilot (Korea)/Pistol Team member who stops by the watering hole now and then. He say’s he can’t explain his vision, either—just that “the damn ten-ring looks like a dinnerplate to me at 50 yards.”
Oh no..I was had...hahaha...
Still...its neat and she’s cute.
Our taxes at work.
Understanding the gravitational...uh, baseball field.
I was there!
(And it's lots more than "hundreds of thousands of YouTube viewers" who have seen this. It is simply the most often replayed video moment in sports history.)
ML/NJ
This is not nearly as puzzling as how a person can take a round bat and hit a round ball...squarely.
Sure ... it's not hard to do ...
But how do you do it? How does your brain process the visual data so you can think the ball is headed some particular place?
It's quite clear that you haven't a clue ... neither do I.
It is, in fact, a very difficult problem. "Artificial Intelligence" and robotics are, in some ways, more difficult disciplines than mere rocket science.
Calculus.
Yowza...I never realized the Polo Grounds’ outfield was that huge. As a kid I was at Ebbets Field (Brooklyn) often, but never went to the Polo Grounds (Manhattan/NYC).
Wow!! You were there...most excellent. I was watching it on TV (the old black and white Dumont!).
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