Foul tip trauma

Mar 30, 2007

Foul tip trauma Inspired by the story of Mike Matheny's retirement, four Kettering students test catcher's masks to see how well they protect major league baseball players.

Putting their engineering education to work in the field of athlete safety, four Kettering University students tested the protective properties of old style and the newer hockey-style catcher's masks. Their findings support one for foul tips and the other for batter backswings.

Their research was inspired by professional baseball catcher Mike Matheny of the San Francisco Giants. During a three-game series against the Florida Marlins, Matheny suffered multiple impacts to his head as a result of foul-tips from Marlin batters. His injuries caused extensive concussion syndrome, which led to his retirement from professional baseball.

"More players are getting concussions taking foul tips (balls that are deflected or redirected by the bat) to the head," said Morris "Mo" Roth, a senior from Commack, N.Y. "Recently, the baseball world has been debating whether or not the new style mask offers adequate protection from head injury," he added, "currently there is no available data on the protective value of catchers' masks so we decided to test the two styles for our Experimental Mechanics class project."

The old style is still commonly used, according to Roth. It is a two-piece design consisting of a traditional style catcher's mask and helmet. The mask is a metal cage with padding across the forehead and over the cheekbones and chin areas, with no padding on the sides of the head (near the temples and ears).

The new style catcher's mask is patterned after hockey goalie masks with a plastic outer shell over a metal frame and padding underneath with protective coverage back to the ear area and up higher over the top of the head in front. The hockey style helmet debuted in 1996 and is becoming more popular each year because of its unique styling and better range of vision or sight lines for the catcher, according to Roth.

Both masks that the group tested were manufactured for professional use by All-Star, a division of Ampac Enterprises.

To test potential injuries caused by foul tips Roth, Scott Barel, a senior from Sterling Heights, Mich., Jeff Schulze, a senior from Bay Port, Mich., and Josh Maag, a senior from Leipsic, Ohio, received permission to use the crash test dummies and high speed video camera equipment in Kettering's Crash Safety Center.

The dummies are instrumented with accelerometers that indicate possible brain or closed-head injuries in humans. The students re-engineered a skeet shooting skeet thrower to swing a baseball in a 180 degree arc striking the helmeted dummy with about 800 pounds of force. The skeet thrower was donated to the project by Dr. Martin Wing, associate professor of Liberal Studies.

All catcher's masks must be tested against forces of 60 mph to be approved for sale, according to Roth, "but this is not realistic in major league baseball where balls are thrown in excess of 90 miles per hour," he said.

While researching the topic prior to testing, the group found that after the Matheny incident, the San Francisco Giants performed their own testing from 84 to 104 mph. The results were not made available to the public, however, the Giants organization has claimed that both the traditional mask and hockey style mask performed equally as well during those impact tests. The methods of the Giants testing are unknown, Roth said.

Using the modified skeet thrower at approximately 100 mph aimed at the crash test dummy's head wearing the two types of catcher's mask, the group measured acceleration, or G-forces, exerted on the head in two different types of test. The first test was a frontal impact test, simulating a foul-tip. The second test was a side impact test, which is more conducive to a batter's backswing striking the side of a catcher's head.

The force data and time data were taken from an oscilloscope reading. The target range for the velocity was 90 to 105 mph. This 15 mph range was based on the velocity at which professional pitchers throw a baseball, taking into consideration that when a ball is tipped by the bat and re-directed into the catcher's mask, it is most likely not traveling the same velocity at which the pitch was thrown.

According to the results of their tests, each mask performs better in different categories. The hockey style mask performed much better than the traditional style mask when the impact was on the side of the mask, representing the backswing impact region of the catcher's head.

The hockey style mask recorded a G-force value of 13.57 in comparison to the traditional style mask recording a value of 32.02. Because the traditional style catcher's mask is a two-piece system, the impact took place on the helmet rather than the actual cage mask. The traditional helmet offers little protection for the side of the head.

However, the traditional style mask performed better when the ball struck the cage, which represented a direct impact to the front of the head occurring on the lower half of the cage. Peak G-force of the traditional mask at this location was 3.763, while peak G-force for the hockey style mask was 9.814.

The students determined the traditional style mask is most protective against frontal impact, while the hockey style mask protects better during side impact. "The reason why the hockey style mask protects better against side impact can be attributed to the flex properties of the material used," according to their report. The flex of the helmet was observed from the images recorded by a high speed camera in the crash test lab.

Their conclusion, based on test results, was that the traditional two-piece system needs to be improved on the area of the helmet, with no change to the cage. "Overall, the testing would support the theory that a traditional style catcher's mask would protect better against a foul-tip and a hockey style catcher's mask would protect better against a hitter's backswing," they said in their report. The front impact location was where the foul-tip that ended Mike Matheny's career struck on the hockey style catcher's mask.

The students are working with Dr. Henry Kowalski, professor of Mechanical Engineering and their instructor for Experimental Mechanics, to contact the manufacturer of the masks they tested to share their findings.

Written by Dawn Hibbard
Support materials provided by Morris Roth, Scott Barel, Jeff Schulze and Josh Maag
810-762-9865
dhibbard@kettering.edu

Four Kettering University students put their engineering education to work testing baseball catchers' masks recently. Inspired by the early retirement due to injury of professional baseball catcher Mike Matheny, of the San Francisco Giants, the four decided to test two common styles of mask for their Experimental Mechanics (MECH 514) class project.

The results of the student's class project testing were published at www.kettering.edu/visitors March 30. The tests performed on the catchers' masks by the students were not comprehensive nor were they intended for peer review.

All-Star Sports, the company that produced the masks tested by the students for their class project, has identified the following issues for clarification related to the students' testing:

The "hockey style" catcher's helmet tested was not the Major League? quality, but rather All-Star's basic Little League/High School "hockey style" catcher's helmet. The Little League/High School "hockey style" catcher's helmet produced by All-Star is a different construction than the helmets All-Star provides to professional catchers.
All-Star's top-of-the-line "traditional" catcher's mask was tested by the Kettering students.
The helmets tested by the Kettering students were tested in two locations (the side of the head and the "nose" of the metal cage). The data presented in the students' final report for these locations were from a single impact only.
All-Star maintains that the safety performance of a helmet cannot be characterized by hitting it once in the "nose" and once on the side.
All-Star maintains the data collected by the Kettering students is not substantiated by multiple, repeated trials.
The numerical figure of 9.814 g was misreported, and is actually 9.184 g.
The impact velocity of each hit was not measured. According to All-Star, the wide variation in the impact velocity does not allow for a fair comparison. (The students calculated the velocity using a change in momentum measurement.)
The students' test findings show that both the "traditional" and "hockey style" helmet are very protective. All of the reported peak g values are very safe, especially when considered within the context of peak g's that lead to concussions.
The lowest peak g value was measured on the forehead of the "hockey style" helmet with a reading of 2.876 g.

Kettering apologizes for any misconceptions about All-Star products resulting from the students' test results.