Name: Daniel Halbing
Major: Physics, Philosophy
Advisors: Dr. Susan Lehman, Dr. Niklas Manz
The predictability of flight of the Adidas Conext15, Adidas Jabulani, Adidas UEFA Nations League, Nike Incyte, Nike Flight, Nike Ordem, and Wilson NCAA Forte match balls were analyzed. Six to nine shots of each match ball were recorded from two angles, a rear angle and a side angle, for this investigation. Each of the videos were uploaded to Tracker in order to collect data on the spin, velocity, initial position, and final position of each of the trials in both the x-and y-directions. The data from the initial 20 frames of each trial was then used to create a theoretical final position of the ball using a radius of curvature of the flight path equation for the x-direction and a differential projectile motion equation for the y-direction. These theoretical final positions were then compared to the measured final positions of the ball in order to see how much the ball had deviated from the theoretical flight path based on the initial flight data. This deviation was then used as the metric for unpredictability in the scope of this investigation. For a soccer ball in general, it was found that a higher spin rate in the x-direction made the ball less predictable when compared to other low spin curved shots. However, in the y-direction, it was found that there was no relationship between the predictability of a ball and the spin rate. As the initial velocity in the y-direction increased, the predictability of the shot decreases. Of the seven balls that were tested, the most predictable ball in the x-direction was the adidas UEFA Nations League which deviated from the theoretical final x-position by an average of 0.78±0.67 m. The most predictable ball in the y-direction was the Wilson NCAA Forte which deviated by an average of 0.27±0.25 m. The most predictable ball overall was the Adidas UEFA Nations League as it deviated from the theoretical final x-position by an average of 0.78±0.67 m and deviated from the theoretical final y-position by an average of 0.29±0.15 m.
Daniel will be online to field comments on April 16:
2-4 pm EDT (PST 11am-1pm, Africa/Europe: evening)