Analyzing Fastpitch Softball
from the 2011 WCWS
Alan M. Nathan
University of Illinois
PITCHf/x @ WCWS
• Sportvision had usual setup for ESPN
broadcast (K-Zone)
• Every pitch tracked
– 3505 total
– 14 of 15 games
• SV sent data upon my request
– Thanks!
Interesting Things to Study
• How do pitches differ from MLB?
– Speed
– Flight time
– Release point and direction
– Spin rate and axis
– Movement
• Some obvious differences
– Pitcher’s rubber is not raised
– Rubber-to-home plate is 43 ft
– Underhand  naturally upward with topspin
• A pitcher’s repertoire
Release
Speed
Release
Speed
Release Height
Release Height
FlightTime
Time
Flight
Vertical Release Angle
Vertical Release Angle
“Drop”
Height at home plate – Height at release
Movement
pfx_x = horizontal movement
pfx_z = vertical movement
Spin Rate and Axis
Spin Rate vs. Speed
Spin Rate vs. Axis
topspin
Henderson
Thomas
Dunne
Some Trajectories
• Same v0
• Note the
“late
break”
• pz differs
by ~1 ft
Some Trajectories
side view
Some Trajectories
side view
• Same v0
• pz differs by
~2 ft
Some Trajectories
• Different v0
• px differs by
~1 ft
side view
top view
…and in conclusion
• Lots of interesting data to look at and
much to be learned
• I have done only cursory analysis thus far
– a fun diversion from my usual activities
• These data ought to useful to softball
players and their coaches
• NOTE: K-Zone also set up for CWS
– the data might be interesting to analyze