What happens to the flight of a baseball once it is scuffed? We decided to find out. We started with a new 2019 MLB ball and fired it 12 times from our WSU cannon. The pitch distance is the standard 60.5 feet. The pitches were just below 90 mph and Continue Reading
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Toward a Better Pitch Tracker: Post 43
All commercial pitch tracking devices either Measure the ball movement and total RPM and compute the active spin and axis based on a Magnus Effect model (Trackman) or Measure the RPM, axis and pitch location and predict the ball path (horizontal and vertical break) based on a Magnus Effect model Continue Reading
Disco Ball Changeup Experiment: Post 42
Background I like to talk about “seam-shifted wake” pitches and I know of two examples, the “laminar express” 2-seamer and the “disco ball changeup.” The best example of the latter that I have seen is Strasburg’s, shown below. As I have noted before, about 10% of his changeups have a Continue Reading
Seam Shifted Wake Axis: Post 41
The Seam Shifted Wake requires a special axis, and it is not through a symmetry point like a conventional 2-Seamer. Note that this explanation holds whether the pitch is a “laminar express” 2-seamer or a “disco ball changeup.
2019 in Review: Post 40
With 2020 around the corner, I thought I’d step back and look at what we have learned. Just about a year ago, I wrote the questions shown below in italics. Below each question, I will describe my current understanding of that topic. What effects baseball drag? Seam height Center of Continue Reading
How Does Pitching Work?: Post 39
I’d like to have a discussion between various the stakeholders of pitching. The three groups I am thinking of are pitchers, analytics folks, and physicists. I hope no one will complain if I put myself (a Mechanical Engineer) in the last category. This will be mostly (or maybe completely) about Continue Reading
Magnus Effect – Seams and Roughness: Post 38
Magnus effect causes a force on a round spinning translating object that is perpendicular to the rotation axis and in the direction that the front surface of the ball is moving. These effects are critical to baseball pitching and also affects batted balls. The question that I’d like to answer Continue Reading
My APS DFD presentation on the Fluid Dynamics of Seam Shifted Wakes: Post 37
On Sunday, November 24, 2019 I will present to the American Physical Society Division of Fluid Dynamics on “The Baseball Seam: Clever and Capable Passive Flow Control” in Seattle. This is basically a spoken, 10 minute version of our video from Post 34. There is a lot more detail here. Continue Reading
The Non-Centered Pill Baseball Drag Theory: Post 36
Here is an excerpt from the MLB Home Run Committee report from 2017. The committee has not yet succeeded in definitively explaining the cause of the decreased drag coefficient beginning in 2015. Various hypotheses have been proposed and tested, including gradual changes in the manufacturing process affecting the centering of Continue Reading
The Seam Shifted Wake: Post 34
This is our video entry for the American Physical Society Gallery of Fluid Motion for 2019. As always, If you are new to our measurements, you may take a minute to read here about vorticity (the colors in our plots), boundary layer separation.