University of Alabama at Birmingham School of Health Professions, Birmingham, AL, United States.
School of Health Professions.
Phys Sportsmed. 2024 Aug;52(4):381-385. doi: 10.1080/00913847.2023.2282381. Epub 2023 Nov 28.
Employ a novel testing method to assess Multi Directional Impact Protection System (MIPS) helmet technology on rotational velocity and acceleration during head impact.
An optimization study was completed utilizing a 50th percentile male Hybrid III anthropomorphic test device (ATD). Helmets included expanded polystyrene foam (EPS) and two different MIPS helmets (MIPS 1, MIPS 2). A 24.38-m-long elevated track with rails and a motorized sled was utilized to replicate a fall from approximately 2.13 m. The sled was set to a speed of 20.92 kph, where a tripping mechanism induced rotation in the ATD from the sled and onto a sand surface. During impact of the ATD with the sand surface, head kinematics were measured using resultant acceleration (peak G's), duration of impact (ms), and rotational velocity (rad/s).
A total of three trials for each helmet did not demonstrate a significant difference between the EPS vs. MIPS 1 group with, peak (G's) for resultant acceleration ( = 0.100), duration (ms) for resultant acceleration, ( = 0.100), peak (G's) for rotational velocity, ( = 0.700), and duration (ms) for rotational velocity ( = 0.700). Similarly, the EPS vs. MIPS 2 testing demonstrated no significant differences between the MIPS 2 helmet compared to the EPS helmet, with resultant acceleration ( = 0.400), duration acceleration ( = 0.200), rotational velocity ( = 0.400) and duration velocity ( = 0.400). However, when the MIPS helmet data were pooled, and the EPS helmet data were compared, a statistically significant difference in the duration of acceleration was found ( = 0.048).
Current testing uses a helmeted head form which is dropped or rolled from a prescribed height. These methods discount the loading placed on the neck and head through the angular momentum of the body. Our novel testing method did not find significant differences between the helmet types in diminishing peak rotational forces to the brain; however, our data suggests that MIPS helmet liners may reduce duration of impact. The reduction of acceleration duration could indicate less rotation of the neck, due to the dampening of these forces by the MIPS liners.
采用一种新的测试方法评估多方向冲击保护系统（MIPS）头盔技术对头冲击时的旋转速度和加速度的影响。
利用 50 百分位男性混合 III 人体模型测试设备（ATD）完成优化研究。头盔包括膨胀聚苯乙烯泡沫（EPS）和两种不同的 MIPS 头盔（MIPS1、MIPS2）。使用一条 24.38 米长的高架轨道和一个带电机的雪橇来复制从大约 2.13 米高处坠落。雪橇的速度设置为 20.92 公里/小时，一个触发机制会使 ATD 从雪橇上旋转并撞到沙面上。当 ATD 撞击沙面时，使用合成加速度（峰值 Gs）、冲击持续时间（ms）和旋转速度（rad/s）来测量头部运动学。
对于每个头盔的三次试验中，EPS 与 MIPS1 组之间的结果加速度（峰值 Gs）（ = 0.100）、结果加速度的持续时间（ms）（ = 0.100）、旋转速度的峰值（Gs）（ = 0.700）和旋转速度的持续时间（ms）（ = 0.700）均无显著差异。同样，EPS 与 MIPS2 测试之间也没有发现 MIPS2 头盔与 EPS 头盔之间的显著差异，结果加速度（ = 0.400）、加速度持续时间（ = 0.200）、旋转速度（ = 0.400）和旋转速度持续时间（ = 0.400）。然而，当汇总 MIPS 头盔数据并将 EPS 头盔数据进行比较时，发现加速度持续时间存在统计学上的显著差异（ = 0.048）。
目前的测试使用从规定高度掉落或滚动的头盔头部模型。这些方法忽略了身体角动量对颈部和头部的加载。我们的新测试方法没有发现头盔类型在减少大脑峰值旋转力方面有显著差异；然而，我们的数据表明，MIPS 头盔衬垫可能会减少冲击的持续时间。加速度持续时间的减少可能表明颈部旋转减少，这是由于 MIPS 衬垫阻尼了这些力。
