Welcome to my site devoted to research on the physics of baseball. My particular research interests are two-fold: the physics of the baseball-bat collision and the flight of the baseball. I have done quite a bit of independent research in both areas. I am also heavily involved with several areas of practical interest to the game. One is characterizing, measuring, and regulating the performance of non-wood bats, an area for which I have served on committees advising the NCAA and USA Baseball. Another is exploiting new technologies for tracking the baseball, such as PITCHf/x, HITf/x, and TrackMan, for novel uses in baseball analytics. But this site does much more than catalog my own work. It attempts to provide links to much of the high-quality work done over the past decade or so on various aspects of the physics of baseball. If readers know of a site that I have overlooked, please contact me.
Recent Research Highlights
Press release by the NCAA announcing a change to the baseball used in Division I championship play starting in 2015. See also the earlier story, NCAA Concludes Study on Ball Seams, by Aaron Fitt that was published in Baseball America October 2, 2013. The article reports new measurements done indpendently by the Sports Science Laboratory at Washington State University and by Rawlings. These measurements show that the air drag on the MLB flat-seam baseball is considerably less than that on the NCAA raised-seam baseball. In the WSU studies, baseballs were launched at a speed of 96 mph, a vertical launch angle of 250, and with 1400 rpm of backspin. Under these conditions, the flat-seam and raised seam balls traveled mean distances of 387 and 367 ft, respectively, a 20 ft difference. The switch from BESR to BBCOR bats starting in 2011 reduced fly ball distances by approximately 35 ft and home runs by a factor of two. Scaling roughly from these data, I estimate that the change from flat- to raised-seam baseballs will result in a >50% increase in home run production if used for an entire season, relative to 2011-2013 numbers using BBCOR bats. That is, more than half of the home runs lost with the new bats will be restored.
Link to a YouTube video of a public lecture I gave in August, 2013 for the Chicago Council on Science and Technology (C2ST). The talk took place at U. S. Cellular Field. It was one of the most enjoyable lectures I have given recently, lots of fun for both me and the audience.
Links to Recent Interviews:
Link to slides of a talk I gave at the August 2013 Saberseminar at Boston University. The slide above shows that if a ball is hit hard (> 90 mph) and at a launch angle in the range 10-12 degrees, it will result in a hit almost 100% of the time. The data are from the April 2009 release of HITf/x.