Looking at baseball using physics

[Nomar4prez]

Found it at this website:

http://www.npl.uiuc.edu/~a-nathan/pob/AJP-Nov03.pdf
A little too long and complicated, but the conclusions were interesting to me atleast. It may not be too interesting to you guys, but since 2/3 of my time in school I use physics, its nice to see it used for something useful. biggrin.gif


IV. CONCLUSIONS
The aim of this study was to establish an optimum strategy
for hitting a baseball. The results we have presented show
the following.
~1! It is important to utilize impact and flight models that are
as realistic and complete as possible. Without accurate
simulations, optimization is pointless. Our flight model
includes the experimental lift and drag coefficient dependence
on Re and spin parameter. The impact model treats
collision relative velocity as a function of impulse and
incorporates the dependence of the energetic coefficient
of restitution e* on the impact relative velocity and the
dependence of the pitched ball angle with the horizontal,
g, on pitch speed.
~2! The bat–ball coefficient of friction m is near 0.50 for
wooden bats and 0.35 for aluminum bats.
~3! Within a realistic range ~0.35–0.50!, the value of mdoes
not affect batted ball spin, velocity, or launch angle.
Therefore, any effort to increase backspin on the batted
ball by increasing mis futile.
~4! The batted ball clearly goes through the drag crisis. The
resulting sharp reduction in drag leads to ranges considerably
larger than would be achieved with a perfectly
smooth ball which would experience drag coefficients
near CD50.5 for much, if not all, of its flight.
~5! There is an optimal strategy for achieving maximum
range. For a typical fastball the batter should undercut
the ball by 2.65 cm and swing upward at an angle 0.1594
rad.
~6! The optimally hit curve ball will travel farther than both
the fastball and knuckleball, because of beneficial topspin
on the pitched curve ball that is enhanced during
impact with the bat.
~7! Range is most sensitive to bat speed, which suggests that
a batter ought to work on bat speed before anything else
to increase the range of his/her hits.
~8! Range is not very sensitive to wrist roll. Attempts to roll
the wrists on impact do not increase range enough for it
to be a useful and advantageous strategy. Wrist roll may
actually limit bat speed, which is clearly more important.
~9! For a given pitch type, range increases with pitch speed.

[WharfRat]

I don't understand all of it, but pretty neat all the same.

[BaseballFann0008]

I don't understand all of it, but pretty neat all the same.

same here lol

[baseball6791]

I don't understand all of it, but pretty neat all the same.

same here lol

Most of it is pretty common sense stuff, just proven and written in a more complex way.

IV. CONCLUSIONS
The aim of this study was to establish an optimum strategy
for hitting a baseball. The results we have presented show
the following.
~1! It is important to utilize impact and flight models that are
as realistic and complete as possible. Without accurate
simulations, optimization is pointless. Our flight model
includes the experimental lift and drag coefficient dependence
on Re and spin parameter. The impact model treats
collision relative velocity as a function of impulse and
incorporates the dependence of the energetic coefficient
of restitution e* on the impact relative velocity and the
dependence of the pitched ball angle with the horizontal,
g, on pitch speed. They used lots of models to test for different situations that could occur with the spin, lift, and drag of the ball (this one is harder for me to understand)
~2! The bat–ball coefficient of friction m is near 0.50 for
wooden bats and 0.35 for aluminum bats. The amount of force need to mantain solid contact with the ball is more for wooden bats than metal, i.e. its harder to hit with a wooden bat
~3! Within a realistic range ~0.35–0.50!, the value of m does
not affect batted ball spin, velocity, or launch angle.
Therefore, any effort to increase backspin on the batted
ball by increasing m is futile. In a certain range, if you try to use more force to create more backspin, it is pointless
~4! The batted ball clearly goes through the drag crisis. The
resulting sharp reduction in drag leads to ranges considerably
larger than would be achieved with a perfectly
smooth ball which would experience drag coefficients
near CD50.5 for much, if not all, of its flight. I'm not sure, but what I think what this means is... first off, I think that the drag crisis is basically a phenomenon in which drag is severly reduced on an object in flight (in this case because the ball has seams and is not perfectly spherical as a result), and because this happens to a baseball, the ball travels much farther than it would if it didn't go through the drag crisis, which would happen if the ball didnt have seams. So basically, because the ball isn't perfectly round, it experiences less drag, and goes farther
~5! There is an optimal strategy for achieving maximum
range. For a typical fastball the batter should undercut
the ball by 2.65 cm and swing upward at an angle 0.1594
rad. To hit the ball farthest, you must swing at a slightly upward angle and try to hit the bottom half of the ball
~6! The optimally hit curve ball will travel farther than both
the fastball and knuckleball, because of beneficial topspin
on the pitched curve ball that is enhanced during
impact with the bat. If you hit a curveball perfectly and a fastball perfectly, the curveball will go farther because the extra topspin on a curveball that isn't on a fastball. This is actually kind of interesting because you would think that a fastball would travel further since the fastball has more velocity in the first place, but I do think that this conclusion is a bit flawed because it does depend on the speed of both the fastball and curveball in question to be exactly the same, and we all know that fastballs go faster than curveballs.
~7! Range is most sensitive to bat speed, which suggests that
a batter ought to work on bat speed before anything else
to increase the range of his/her hits. Bat speed is the biggest factor in how far you hit the ball, so if you want to hit the ball farther improve your bat speed
~8! Range is not very sensitive to wrist roll. Attempts to roll
the wrists on impact do not increase range enough for it
to be a useful and advantageous strategy. Wrist roll may
actually limit bat speed, which is clearly more important. Trying to roll your wrists (to create more spin?) at contact doesn't increase the distance you hit the ball, it actually may decrease it since it decreases bat speed
~9! For a given pitch type, range increases with pitch speed.The faster the ball is pitched, the further the ball is hit