Effect of different helmets against ground impact based on the in-depth reconstruction of electric two-wheeler accidents

Abstract

Skull fracture and brain injury are frequent head injuries in electric two-wheeler (ETW) accidents, and the type of helmet and impact conditions affect the effectiveness of the helmet in protecting the rider’s head. The purpose of this study was to conduct in-depth reconstructions of rider’s head-to-ground impacts in ten ETW accidents by using a multi-body system combined with a finite element approach and to evaluate the effect of two typical full-face helmets (FFH) and one half-coverage helmet (HCH) through head accelerations and intracranial biomechanics injury metrics in ground impacts. The results showed that all three helmets reduced the risk of skull fracture in most cases, however, FFH performed better due to its wider protection area. In addition, three helmets showed varying degrees of overall reduction in measuring all indicators of brain injury. Although the effectiveness of the helmets on angular acceleration was largely influenced by the angle and location of impact, it was certain that wearing an FFH was more likely to reduce rotational head movements than an HCH, and that the FFH also offered the better advantage in reducing diffuse axonal injury (DAI) risk due to its better resistance to ejection in a crash.

Keywords:

• Electric two-wheeler accidents
• in-depth accident reconstruction
• head-to-ground impact
• full-face helmet
• half-coverage helmet
• finite element analysis

Acknowledgement

The authors would like to acknowledge the support of the Natural Science Foundation of China (Grant Nos. 51775466), and Fujian Provincial Science Foundation for distinguished young scholars (Grant No. 2019J06022), the Key lab of Forensic Science Open-Ended Foundation of the Ministry of Justice (Academy of Forensic Science) (Grant No. KF202116); and this work also is supported by Xiamen YUQUAN composite technology supplying the 3D helmet model and test data for validation.

Disclosure statement

The authors declared that they have no conflicts of interest to this work.

Additional information

Funding

The authors would like to acknowledge the support of the Natural Science Foundation of China (Grant Nos. 51775466), and Fujian Provincial Science Foundation for distinguished young scholars (Grant No. 2019J06022), the Key lab of Forensic Science Open-Ended Foundation of the Ministry of Justice (Academy of Forensic Science) (Grant No. KF202116); and this work also is supported by Xiamen YUQUAN composite technology supplying the 3D helmet model and test data for validation.