Who is more vulnerable in crashes between motorized 2-wheelers and pedestrians?

Numerical investigation of the rider's head injury in typical single-electric self-balancing scooter accident scenarios

As the use of electric self-balancing scooters (ESSs) increases, so does the number of related traffic accidents. Because of the special control method, mechanical structure and driving posture, ESSs are prone to various single-vehicle accidents, such as collisions with fixed obstacles and falls due to mechanical failures. In various ESS accident scenarios, the rider's head injury is the most frequent injury type. In this study, several typical single-ESS accident scenarios are reconstructed via computational methods, and the risk of riders' head/brain injury is assessed in depth using various injury criteria. Results showed that two types of ESSs (solo- and two-wheeler) do not have clear differences in head kinematics and head injury risks; the head kinematics (or falling posture) and ESS accident scenario exhibit a distinct effect on the head injury responses; half of the analysed ESS riders have a 50% probability of skull fracture, a few riders have a 50% risk of abbreviated injury scale (AIS) 4+ brain injury, and none has a diffuse axonal injury; the ESS speed plays an important role in producing the head/brain injury in ESS riders, and generally, higher ESS speed generates higher level of predicted head injury parameters. These findings will provide theoretical support for preventing head injury among ESS riders and data support for developing and legislating ESSs.

Characteristics of pedestrian injuries caused due to impacts with powered 2-wheelers in India

Objective: This study aims to understand the nature, severity, and sources of injuries sustained by pedestrians involved in crashes with powered 2-wheelers (PTWs) in India. Further, it aims to understand the pedestrian injury pattern and injury mechanism based on the pedestrian contact location on the PTW. Methods: Eight years of field data from the Road Accident Sampling System-India (RASSI) database were considered for the study. Analyses were performed using both weighted and unweighted RASSI data. A sample of 57 crashes between pedestrians and PTWs was analyzed to determine the pedestrian injury characteristics, pedestrian orientation with PTW, and PTW contact zone (PCZ) or the pedestrian contact location on PTW. The PCZs were classified into 3 types. The risk of sustaining a Maximum Abbreviated Injury Scale (MAIS) injury to the head and pedestrian injury mechanism across the 3 PCZs was analyzed. Results: The results of both weighted and unweighted RASSI data were consistent. About 67% of pedestrians who were killed sustained MAIS 3+ head injuries and 52% of pedestrians with nonfatal injuries sustained MAIS 2+ lower extremity injuries. The risk of MAIS 3+/fatal head injury is notably higher (86%) for pedestrians struck from behind compared to pedestrians struck from the side (36%). Of the 3 PCZs, about 80% of the pedestrians contacting PCZ-1 (corner of the PTW front end) sustained fatal head injuries and only 5% contacting PCZ-2 (center of the PTW front end) sustained fatal head injuries. About 40% contacting PCZ-3 (combination of PCZ-1 and PCZ-2) sustained fatal head injuries. Of all AIS 3+ head injuries, 88% were associated with ground impacts. Of all AIS 2+ lower extremity injuries, 96% were associated with impacts to PTW front-end parts. Conclusions: The results show that head injuries account for most pedestrian fatalities in crashes with PTWs and lower extremity injuries account for most nonfatal injuries. Head injuries are associated with ground contacts and lower extremity injuries are associated with contacting PTW front-end parts. Pedestrians contacting the corner of the PTW are highly prone to MAIS 3+ head injuries, whereas pedestrians contacting the center of the PTW are less prone to MAIS 3+ head injuries. This difference is predominantly because of the varied injury mechanisms seen across PCZs.