Citation

Ruth R, Reust T. Collision 2009; 4(1): 32-39.

Copyright

(Copyright © 2009, Collision Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The time lag between the last data point recorded by an event data recorder (EDR) and the actual crash can lead to potential overreporting of speed at impact. New Chrysler EDRs record precrash speed data at more frequent intervals than earlier EDRs, which allows for a more precise determination of speed at impact. However, Chrysler vehicles record vehicle speed from a sensor on the transmission output shaft that rotates proportional to wheel speed. Braking slows the wheels and causes the vehicle speed to be underreported. This article quantifies the degree of underreporting during maximum pedal force application from two Chrysler 2008 vehicle models. By quantifying the brake underreporting and the time lag overreporting, the most accurate speed at impact can be obtained.