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5000 fps Camera Reveals the Physics of Baseball
concealment sends this quote from an article at The Physics of Baseball "This clip from Game 4 shows Marco Scutaro hitting the ball right near the tip of the barrel. The amplitude of the resulting vibration is so large that the bat breaks and the ball weakly dribbles off the bat. Note that the bat splinters toward the pitcher. The reason is that when the ball hits the barrel tip, the barrel of the bat bends backward toward the catcher and the center of the bat bulges forward toward the pitcher. That is the natural shape of the fundamental vibrational mode of the bat. Since the fracture occurs near the center which is bulging outward, that is how the bat splinters, as the wood fibers on the pitcher side of the bat are stretched to the breaking point. If the ball had impacted the bat near the center, the center would have bulged toward the catcher, as in the Yadier Molina clip. Had the vibrational amplitude been strong enough in the Molina case, the bat would have splintered toward the catcher."
First pitch!
Great, way to make the game orders of magnitude longer.
The bat doesn't break the way they describe.
1) It doesn't bend in the middle, it bends close to the fixed end (where it is being held).
2) What they describe is not the fundamental mode shape of a held bat. They are describing a free-free beam, but bats are usually held.
3) It does bend similar to its fundamental mode shape. But it's not breaking due to vibration. It's being deflected by an impulse load and breaking.
Simple engineering, and they got it wrong.
Not only is a variable being ignored its nearly the central reason for all the hoopla in this story. For all the millions of dollars wasted on major league players you would think that holding the main tool of the game properly would be a given but its not. Old timers from the dawn days of baseball knew this but it seems to have been forgotten sometime in the past 50 years. If these yahoos that call themselves pros really wanted to pound the ball they would learn how to hold the damn bat properly and not in such a way that it flexes excessively or breaks, both of which is an incomplete transference of the energy from batter to ball. The bat has a grain like all wood and this grain runs along the side of the bat at 90 degrees to the label. Holding the bat with the label up or down causes this area of bat to be the main contact area. "With the grain" the bat is much stronger and stiffer transferring more of the batters' energy to the ball and of course flying further. "Across the grain" the wood is weaker and more likely to flex or break as the fibers deform. No one has ever broken a bat "with the grain." In the bat breaking sequence you can clearly see the label is nearly square on to the direction of the pitch. The other vids aren't as easy to see the orientation of the bat but the excessive flex is telling. This "researcher" needs to find a player who knows how to hold the bat properly and repeat said observations. Then he will discover what the old timers who played in cornfields knew a century ago.
Power tends to corrupt, and absolute power corrupts absolutely.
The author originally wanted to use the New York Yankees as the focus... However, he was unable to capture enough examples of Yankee batters making contact with a baseball during the ALCS to complete the study.