Bending modes, damping, and the sensation of sting in baseball bats

The painful sensation of sting in the top hand of a player holding a baseball or Softball bat may be a deterrent to enjoying the game, especially for young players. Several mechanisms for reducing the vibration of bending modes have been implemented in youth baseball bats in order to reduce sting. One method of assessing the effectiveness of these mechanisms is to compare the damping rate they provide for the first two or three bending modes in a bat. Damping rates are compared for several wood, aluminum, composite, and two-piece construction baseball bats, in addition to several bats with special damping control mechanisms. Experimental evidence suggests that damping mechanisms which reduce the vibration of the second bending mode arc preferred by players. A novel dynamic absorber in the knob is shown to effectively reduce the vibration of the second bending mode and minimize the painful sting felt in the top hand.