Methods for quantifying the impact severity of low-speed side impacts at varying angles

Accurately quantifying the severity of minor vehicle-to-vehicle impacts has commonly been achieved by utilizing the Momentum Energy Restitution (MER) method. A review of the scientific literature revealed investigations assessing the efficacy of the MER method primarily for: 1) inline rear-end impacts, 2) offset rear-end impacts, and 3) side impacts configured with the bullet vehicle striking the target vehicle at an approximate 90° angle. To date, the utility of the MER method has not been examined and readily published for quantifying oblique side impacts. The aim of the current study was to observe the effectiveness of the MER method for predicting the severity of side impacts at varying angles. Data were collected over a sequence of 12 tests with bullet-to-target-vehicle contact angles ranging from approximately 45° to 135° with corresponding impact speeds of approximately 13.7 km/h to 16.4 km/h. Vehicle damage profiles documented after each test allowed for the application of the MER method to calculate the target vehicle’s change in velocity (ΔV). Calculated ΔV’s were then compared to the vehicle’s recorded change in velocity obtained from instrumentation mounted within the vehicle. The resulting comparisons indicated that the use of the MER method served as an effective means for predicting the severity of minor oblique vehicle-to-vehicle side impacts. Findings obtained from the subject study were particularly relevant due to post-accident vehicle conditions serving as the critical, and often sole, physical evidence available after a minor vehicular accident.