Jury Idiocy Comes to Montana

[SkinnyFats]

Table 3 Average batted-ball speeds and available pitcher reaction times

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Tester       Bat type      ABBS25 (m/s)       APRT (s)
1           Composite        41.8              0.365
1              Wood          36.0              0.423
2           Composite        40.2              0.379
2              Wood          36.0              0.423
3           Composite        40.3              0.378
3              Wood          36.4              0.419
4           Composite        39.1              0.390
4              Wood          33.7              0.452
All          Composite       40.3              0.378
All            Wood          35.5              0.429

This study demonstrates that composite-based slow-pitch softball bats perform at an unsafe level when the results are compared to published safety studies in the sports of softball and baseball

http://journals.pepublishing.com/content/d5h43631355j2jh4/fulltext.pdf

[Joe]

Aside from meeting market demand, bat manufacturers should have nothing whatsoever to do with it.

Game, set, match!

All else is just slowing down HB's server.

[Busted Shins]

I wonder if these parents would have sued if no one had come forward with a sales pitch about how they needed to pursue a big claim to “help” teach these big corporations a lesson and “help” make sure that the same thing would not happen to someone else (don’t worry about expenses, we’ll take it on a 33% contingency).

Notice the use of “help.” This way, no one has to learn anything, and nothing has to change, and the sales pitch is still valid.

[Skarp]

A recent study [Nicholls, et al., 2003] investigated player safety concerning ball exit speed for the sport of baseball and concluded that the maximum safe initial batted-ball velocity that a pitcher can react to is approximately 148 km/h (92 mph), which translates into an APRT of 0.425 seconds.

Interesting. 0.425 is a pretty specific number. How did they arrive at it? Obviously, reaction time isn't a mathematical constant, but varies from player to player (probably substantially) based on myriad factors, such as athletic ability, pitch delivery style, etc.

So how was reaction time tested, and how were the results of that testing generalized? Does 0.425 represent the reaction time of the slowest reactor? The average? For what percentage of players is 0.425 seconds too little time?

In other words, by what rationale was a reaction time of 0.425 seconds deemed "safe?"

I'm not challenging the conclusion...just trying to understand it.

[Crabby_Bob]

Then there is this [kettering.edu] suggesting somewhat lower numbers. Russell further states, "However, a pitcher who is out of position after his follow-through would need an additional 0.1 seconds and might not be able to avoid being hit by balls leaving the bat faster than 90-mph."

[SkinnyFats]

Here's a link to the abstract from the Owings study that came up with the .409 number for 16 year olds. It contains some information about the test methodology. The article Bob linked also references this study, when it says

I am aware of only one field study of reaction times published in a peer-reviewed journal and it deals with reaction times for children ages 9-16 with distances and ball speeds appropriate for Little League baseball

http://journals.lww.com/acsm-msse/Abstract/2003/08000/Influence_of_Ball_Velocity,_Attention,_and_Age_on.22.aspx

[SkinnyFats]

Here's the abstract from the Nicholls study.

Ball exit velocity (BEV) was measured from 17 experienced baseball hitters using wood and metal bats of similar length and mass but different moments of inertia. This research was conducted in response to safety issues for defensive players related to high BEV from metal baseball bats reported in the literature. Our purpose was to determine whether metal bats, with their lower swing moment of inertia, produce a higher linear bat tip velocity than wooden bats swung by the same players. Analysis using high-speed videography indicated significant differences in the x-component of velocity for both the proximal (metal = 5.4 m s~(-1); wood = 3.9 m s~(-1)) and distal ends of the bats (metal = 37.2 m s~(-1); wood = 35.2 m s~(-1)), p < 0.01. The orientation of the bats with respect to the horizontal plane was also significantly more "square" 0.005 s prior to impact (270°) for the metal (264.3°) compared with the wood bat (251.5°), p < 0.01. Mean BEV from metal bats (44.3 m s~(-1)) was higher than the 41 m s~(-1) velocity which corresponds to the minimum movement time for a pitcher to avoid a ball hit in his direction (Cassidy & Burton, 1989).

Note 41 m/s = 92 mph. Also note that Nicholls references the Cassidy and Burton study, and states that Cassidy indicates 400 msec of reaction time is necessary. The article Bob links also references Cassidy, but reads it's results as 325 msec. All other references I've seen to Cassidy refer to significantly higher reaction times than 325 msec.

Cassidy and Burton (1989) indicated 400 msec is required for a pitcher to complete a reactive movement to avoid being struck by the batted ball.

http://fulltext.ausport.gov.au/fulltext/2001/acsms/papers/NICH.pdf

Our results suggest ball exit velocity from wood bats swung by live hitters is within, but at the upper limit of, human reaction time for defensive players. The finding that average exit velocity from metal bats was 43.98 m/s (98.95 mph), and as high as 120.97 mph, indicates a high potential for impact injury to fielding players.

The Nichols study that refers to a safe APRT of 0.425 seconds is here:

Nicholls RL, Elliot BC, Miller K, et al. Bat kinematics in baseball: implications for ball exit velocity and player safety. J Appl Biomech 2003;19:283–94.

And just to avoid confusion between the 400 msec number and the 420 msec number, they are referrring to the same thing. 400 msec is a calculated APRT based on ball exit speed, without taking deceleration of the ball into account.

However, if deceleration due to air resistance is factored in, the resulting APRT would be higher. Based on baseball deceleration calculations performed by Adair7 and substituting the physical properties of softballs, the deceleration due to air resistance in slowpitch softball can be calculated. If deceleration were taken into account for slowpitch softball, a softball would decelerate approximately 9.4% during the first 15.24 m of travel. Therefore the mean speed for a softball starting at 137.2 km/h would be 130.8 km/h—that is, 137.2 x (1 - (0.094/2)) km/h. Therefore the resultant APRT for an mean softball speed of 130.8 km/h would be 0.420 second.

[SkinnyFats]

And finally, the results of another similar softball study, which also used live hitters.

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Table 3 available pitcher reaction time (APRT; seconds)
Bat material           Mean APRT
Titanium                 0.372
Composite                0.361
Aluminium multi-wall     0.387
Aluminium single wall    0.409

[SkinnyFats]

One more pile of drivel, then I better get something done before I get fired.

Angle of concern was mentioned in this topic. Geometry is fighting against our girls here - a ball that hits a softball pitcher right between the eyes will pass harmlessly over the head of a baseball pitcher standing 20 feet further back. There's approximately a 6.3 degree window in which a ball has to travel to strike somewhere on the body of a 6'2" baseball pitcher standing 56' from the plate. A 5'8" pitcher standing 35' from the plate has a 9.2 degree window in which she can be struck. Our softball pitcher has around a 50% greater probability of being struck than a baseball pitcher. And it is probably worse than that, since a baseball pitcher's motion causes him to lean forward significantly, reducing his height. The softball pitcher is standing more upright in comparison. Perhaps this gives the softball pitcher a greater chance to defend herself, perhaps not. But she certainly presents a much larger target for the ball.

Add to that the gender difference in reaction times (which is decreasing over time, and isn't large, but definitely exists), and a larger safety margin should exist for softball players over baseball players.

[tcannizzo]

Excerpt from http://paws.kettering.edu/~drussell/bats-new/ban-safety.html
Physics and Acoustics of Baseball & Softball Bats
Daniel A. Russell, Ph.D.
Applied Physics, Kettering University, Flint, MI 48504-4898

How Much Time does a Pitcher Need to React to Ball Hit Directly Towards Him?
This is the all important question. Unfortunately the topic of pitcher reaction time does not seem to be something that has been extensively studied and published in the research literature. I am aware of only one field study of reaction times published in a peer-reviewed journal and it deals with reaction times for children ages 9-16 with distances and ball speeds appropriate for Little League baseball[12] instead of high school or college baseball. I am aware of three field studies of reaction times for college pitchers, but none of them have gone through the peer-review process and been published. The graphic at right compares the available pitcher reaction time (ball arrival time) as a function of batted ball speed (blue curve) and the measured reaction times for college pitchers from the three unpublished studies.

In 1989 P.E. Cassidy and A.W. Burton at the University of Minnesota investigated the response times of college baseball pitchers and infielders in an unpublished dissertation[13] I haven't yet been able to obtain a copy of this dissertation to read it myself, but Dr. Trey Crisco summarized their conclusions in his report to the NCAA[14]. Cassidy and Burton apparently surveyed the available literature on human reaction times in sports activities, and concluded that an average college baseball player is able to begin an accurate response to a batted ball within 0.125s of the ball being hit, and can complete a reasonable movement to catch, deflect or avoid the ball in an additional 0.200s. The total reaction time for a college player, according to Cassidy and Burton, is about 0.325 seconds.

In 1998 Dr. Richard Brandt, a physics professor at New York University, conducted an experimental study of physical reaction times for college baseball players.[15] A total of 320 balls were fired from a pitching machine at speeds between 85 and 105 mph towards 8 different college pitchers. The subjects were standing behind a protective screen at distances 20, 30, 40, and 50 feet from the pitching machine. Subjects were not able to determine the direction at which the ball was being aimed, and the subjects were tested to see whether or not they could successfully deflect a ball being fired towards them (the protective screen prevented the subjects from being injured). Dr. Brandt found that for college baseball players, a minimum of 0.368 seconds was sufficient to successfully deflect an approaching ball. Dr. Brandt's results suggest that a college pitcher should have sufficient time to avoid being hit at 97-mph by a ball hit from a wood bat, ball hit at 102-mph from a legal high performance metal bat, and even a ball hit by a wood or metal bat with a batted-ball speed of 110-mph.

In 2003 Kevin Breen conducted an unpublished study of potential response time of college baseball pitchers to balls hit in their direction.[16] This study used actual pitchers and batters. The pitcher threw the ball and then had to react from his follow-through position and attempt to deflect the ball batted back directly towards him. Breen's study found that the average response time (the time between the ball was hit and the pitcher first began to move in response to seeing the ball) was 0.176s. When this response time was added to the time the pitcher took to move his body to avoid or deflect the batted ball, he found that every pitcher in his study was able to successfully avoid or deflect a batted ball within 0.300 seconds. This corresponds roughly to a batted-ball speed of 123-mph. Breen estimated that a 5-7 mph difference in batted ball speed would amount to a difference in arrival times of 0.015-0.023s which he concluded is far too short a period of time to make any difference as to whether or not a pitcher could avoid being hit by a batted ball. Mr. Breen's study suggests that college pitchers have enough time to react to balls hit by both wood and metal bats at speeds typical of the college game.

A very interesting observation from Mr. Breen's study is his conclusion that . . .

. . .the largest determining factor in whether a pitcher will be struck by a batted ball is whether the pitcher puts himself in a position to field the ball after delivery. Pitchers are coached to finish their follow through in a way that allows them to be in a position to field any ball that might be hit their way. If a pitcher fails to pitch in a manner so as to be prepared to field, there is a risk that the pitcher will be hit regardless of whether the ball is struck by an aluminum or wood bat. This is because a pitcher who improperly positions himself upon throwing a pitch can easily add well over 0.1 seconds to his reaction time.

If we summarize the results of these three studies we find that a college pitcher should be able to react and either deflect or avoid a ball hit at 120-mph, and would certainly be able to avoid being struck by a ball hit at 110-mph. Thus, a college pitcher should be able to react to the majority of balls hit by both wood and metal bats. However, if the pitcher is out of position so that he is not ready to field a ball hit directly towards him, he might not have enough time to avoid being struck by balls hit by wood or metal bats at speeds as low as 90-mph.