Numerical Assessment of a Safety System to Minimize Injuries during a Cyclist Run-Over.

Area of Science:

• Biomechanical Engineering
• Road Safety Research
• Trauma Prevention

Background:

• Road traffic accidents cause 1.35 million deaths annually worldwide.
• Overtaking run-over scenarios pose a significant risk to vulnerable road users.
• This study investigates a passive safety system to mitigate injuries in such incidents.

Purpose of the Study:

• To evaluate the effectiveness of a passive safety system in reducing injuries during bicycle overtaking run-over events.
• To compare injury severity with and without the passive safety system across different impact speeds.

Main Methods:

• Numerical simulations were conducted using LS-Dyna®.
• Head Injury Criterion (HIC) and Combined Thoracic Index (CTI) were calculated.
• Simulations were performed at three impact speeds: 40, 50, and 60 km/h.

Main Results:

• The passive safety system reduced HIC scores across all tested speeds (40, 50, 60 km/h).
• HIC scores decreased from 3325, 1510, 1208 (without system) to 2605, 1282, 730 (with system) respectively.
• Thoracic injury reduction was noted only at the 40 km/h impact scenario.

Conclusions:

• The passive safety system demonstrates a clear benefit in reducing head injuries for vulnerable road users in run-over incidents.
• The system effectively lowers the probability of cranioencephalic lesions.
• Thoracic injury mitigation is speed-dependent, observed primarily at lower impact velocities.