As more awareness spreads about the risk of concussions in professional sports, many players have begun to wear electronic sensors that can measure head impacts. The devices track impacts and sudden movements, and if it senses a concussion-strength force, it alerts trainers, coaches, or the team doctor. However, a study from Washington State University reveals that these sensors are not currently suited for all sports.
Researchers made use of the Washington State University’s Sports Sciences Laboratory, the official baseball bat testing facility for the National Collegiate Athletic Association. A dummy was outfitted with a non-helmeted impact sensor, the kind worn on mouth guards, headbands, as a patch, or as an earpiece. Researchers then used a pneumatic cannon to fire balls at the dummy. Lacrosse balls, soccer balls, and softballs were fired at varying speeds and angles at the dummy’s chin and forehead. The speeds were meant to simulate real game conditions.
While the sensors were able to properly measure the impact of the slower, softer balls, researchers found that the harder and faster blows—particularly from a softball—were not accurately reported. Impact sensors collect a large amount of data in a short span of time and need to process it very quickly. If the data comes in too fast, such as from a strong, fast hit, certain elements are missed. In particular, the sensors missed the peak of acceleration during the strong hits. This is a problem because that peak has one of the highest potentials of causing a concussion.
Additionally, the sensors had trouble measuring rotational acceleration, when the head twists. Since blows that twist the head have a higher concussion risk than direct hits, this is another important gap in performance. The team is working with the manufacturers of non-helmeted sensors to close these gaps and improve the data processing ability of the impact detectors. Helmeted sensors do not have the same problems as non-helmeted ones because they are able to measure the impact against the helmet itself.
Sources for Today’s Article:
Nevins, D., et al., “Laboratory Evaluation of Wireless Head Impact Sensor,” Procedia Engineering August 25, 2015; 112(2015): 175–79, doi: 10.1016/j.proeng.2015.07.195, http://www.sciencedirect.com/science/article/pii/S1877705815014447.