Evaluating the Accuracy of Speed Change Data Downloaded from Airbag Systems After Offset and Oblique Crash Tests 2020-01-1327
Data downloaded from event data recorders (EDRs) integrated into the airbag systems of passenger vehicles can be key evidence for collision investigators. Often the data includes information about the severity of the collision in terms of the longitudinal and lateral speed change experienced by the vehicle. Previous studies have shown that for collisions with small lateral speed changes, the accuracy of the reported longitudinal speed change varies with manufacturer and magnitude. The goal of this study was to quantify the accuracy of EDR speed changes in high-speed angled collisions.
The reports of twenty-five crash tests in the National Highway Traffic Safety Administration’s Frontal Oblique Offset Testing Program include data from on-board accelerometers as well as data downloaded from EDRs. The accuracy of the EDR speed change was evaluated by calculating the relative error with the longitudinal and lateral speed changes calculated from the on-board accelerometers. The error ranged from 0 % to 20 % for the reported longitudinal speed change and from 3 % to 41 % for lateral speed change, with an outlier test at 315 % error. The error of the resultant speed change was as high as 21 %. There was a significant variation in accuracy between models from the same manufacturer.
The results of this study provide further understanding into the accuracy of EDR reported speed change in high-severity angled collisions.
Jean-Loup Curtat, Craig Wilkinson, Gunter P. Siegmund