Dyson School of Design Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
The Computational, Cognitive and Clinical Neuroimaging Laboratory, Division of Brain Sciences, Imperial College London, London, W12 0NN, UK.
Sci Rep. 2019 Mar 5;9(1):3471. doi: 10.1038/s41598-019-39953-1.
Traumatic brain injury (TBI) affects millions of people worldwide with significant personal and social consequences. New materials and methods offer opportunities for improving designs of TBI prevention systems, such as helmets. We combined empirical impact tests and computational modelling to test the effectiveness of new viscoelastic add-on components in decreasing biomechanical forces within the brain during helmeted head impacts. Motorcycle helmets with and without the viscoelastic components were fitted on a head/neck assembly and were tested under oblique impact to replicate realistic accident conditions. Translational and rotational accelerations were measured during the tests. The inclusion of components reduced peak accelerations, with a significant effect for frontal impacts and a marginal effect for side and rear impacts. The head accelerations were then applied on a computational model of TBI to predict strain and strain-rate across the brain. The presence of viscoelastic components in the helmet decreased strain and strain-rate for frontal impacts at low impact speeds. The effect was less pronounced for front impact at high speeds and for side and rear impacts. This work shows the potential of the viscoelastic add-on components as lightweight and cost-effective solutions for enhancing helmet protection and decreasing strain and strain-rate across the brain during head impacts.
创伤性脑损伤 (TBI) 影响着全球数以百万计的人，给个人和社会带来了重大影响。新材料和方法为改进 TBI 预防系统（如头盔）的设计提供了机会。我们结合了经验性冲击试验和计算建模，以测试头盔头部冲击时，新型黏弹性附加组件在降低脑内生物力学力方面的有效性。将带有和不带有黏弹性组件的摩托车头盔安装到头颈组件上，并在模拟真实事故条件的斜向冲击下进行测试。在测试过程中测量了平移和旋转加速度。组件的包含降低了峰值加速度，正面冲击的效果显著，侧面和后面冲击的效果边际显著。然后将头部加速度应用于 TBI 的计算模型，以预测大脑的应变和应变速率。头盔中黏弹性组件的存在降低了低速正面冲击时的应变和应变速率。对于高速正面冲击和侧面及后面冲击，效果不那么明显。这项工作表明，黏弹性附加组件作为减轻头盔重量和降低头部冲击时大脑应变和应变速率的轻量且具有成本效益的解决方案具有潜力。
