The Hell It Don't Curve

Program Overview

"The Hell It Don't Curve" is a graphical simulator of the path a pitched baseball travels on its way from a pitcher's mound towards homeplate in a live baseball game. The program demonstrates the effects of velocity, spin, and direction on the trajectory of a flying ball. The user may provide values for these parameters, and can see the results in a variety of views.

Features List

1. Realistic modeling of baseball flight using an advanced physics calculation.
2. Text boxes and other GUI elements available to manually specify values for each flight parameter.
3. A real-time animation of the flight of the ball, seen from a variety of perspectives. These include behind home plate, the pitcher's mound, above the infield, third-base, and directly behind the ball following its path.
4. Option to slow down the simulation to 1/2, 1/4, and 1/8-realtime speeds.
5. For each pitch, a determination if the pitch was a strike or ball, with an on-screen strike zone for manual inspection.
6. A "tracking" mode, where the path of the ball is calculated and displayed as a curve from the release point to where the ball lands.
7. A pre-calculated list of standard pitches to automatically select appropriate input values for a variety of pitches. These pitches include a fastball, curveball, slider, split-fingered fastball (also called a "forkball"), and screwball.

Program Use

Launch the application by double-clicking BaseballApp.exe. You will be presented with a screen layout similar to the image at the beginning of this manual. The application consists of two windows, the viewing window and the input toolbar:

Viewing Window

Input Toolbar

The visual simulation of baseball pitches is shown in the viewing window. The input toolbar is used to specify values for each parameter of a pitch (explained later). Use the toolbar to select one of the pre-generated pitches from the Example Pitches combo box. Doing so will fill in the text boxes in the toolbar with values reflecting the selected pitch. For example, selecting Curveball from the Example Pitches will produce the following values:

Toolbar Operation

The following pitch parameters can be tweaked using the input toolbar:

• Velocity: the initial speed of the baseball, in miles per hour (mph).
• Spin: the angular velocity of the baseball around the X, Y, and Z axes, in radians per second (rad/s). Spinning around each axis has the following effects:
  • X-axis: negative spin causes the baseball to drop. Positive spin causes the baseball to "rise" (only slows the rate of descent in reality, but such a pitch is commonly called a "rising" pitch because it appears to rise to the batter).
  • Y-axis: negative spin causes the ball to curve horizontally to the right. Positive spin causes the ball to curve horizontally to the left. Sliders, curveballs, and screwballs utilize spin about the Y-axis to "break".
  • Z-axis: no effect on ball movement, only cosmetic.
• Orientation: the initial rotation of the ball when pitched, in degrees (deg). Though the effect is merely cosmetic, the orientation can be used to graphically simulate the pitcher's grip on the ball when it is thrown.
• Aim: the direction in the XY plane the pitch is initially thrown in. A positive X value aims the pitch to the left (from the pitcher's point of view!), while a positive Y value aims the pitch upwards. An X aim of 3 degrees will cause a straight pitch (like a fastball) to pass directly over home plate.

Overview of example pitches:

• Fastball: an unusually fast, four-seam fastball. The ball is thrown such that the batter sees two pairs of seams for each rotation of the ball, giving the pitch its name. The positive spin about the X axis causes the pitch to "rise", resulting in the nickname "rising fastball".
• Curveball: a pitch that is much slower than a fastball but drops faster than normal with a medium amount of horizontal displacement. The example curveball is typical of the "overhand curve", which is thrown nearly directly overhead and features a larger vertical drop than horizontal. Other varieties of curveballs break more horizontally but less vertically, depending on grip and spin.
• Slider: with a high rotation about the Y-axis, the slider features a significant break horizontally when thrown. A slider can be thrown close to the speed of a fastball and moves less overall than a curveball, but its high velocity makes it a very deceiving pitch, as it often looks like a fastball.
• Forkball: also called a "split-fingered fastball", the forkball is thrown with the index and middle fingers spread wide about the narrow pair of seams on the ball, requiring large and strong hands to grip. The forkball has a high velocity and a moderate negative spin about the X-axis, which causes the ball to drop quickly towards the end of its flight. Some pitchers throw a "sinker", which has the same rotation as the forkball but is easier to grip and throw.
• Screwball: this pitch has a similar spin to the curveball, but instead of breaking away from the pitcher's throwing arm, it moves towards it due to its opposite spin about the Y-axis. It is very difficult to throw because it involves rotating the wrist in an unnatural way, but can be very tricky to see and hit.
• Underhand: an example of an underhand pitch thrown in slow-pitch softball games. Something silly to demonstrate the flexibility of the pitching model :).

If you close the toolbar and wish to see it again, go to the Tools menu and select Show Toolbar.

Tips and Tricks

• Before manually specifying pitch values, try out each of the example pitches to get a feel for how each pitching parameter effects the flight of the baseball.
• When tracking a pitch's path, it is helpful to examine it from the Aerial and Side camera positions.
• Be sure to review the Toolbar Operation section when creating your own pitches to ensure you're choosing the right signs for your spin rates.
• Try creating the following pitches when first trying manual parameter specification:
  • Cutter (cut fastball): between a slider and fastball in speed, with less horizontal displacement than a slider.
  • Slurve: combination slider and curveball. Moves more horizontally than a curveball (but less than a slider) and more vertically than a slider (but less than a curveball).
  • Two-seam fastball: almost as fast as the four-seam fastball, but with a slight negative spin about the x-axis, causing it to dip slightly (but less than a forkball).
  • Change-up: same orientation, spin, and aim of a fastball, but 10 to 15 mph slower.