Forensic Engineering Tools and Analysis of Heavy Vehicle Event Data Recorders (HVEDRs)

Abstract

Since the 1990s, domestic passenger vehicles have been equipped with increasingly more sophisticated supplemental restraint system event data recorders (EDRs) that have become more commonplace in collision analysis. Many collision analysts are aware that most heavy commercial vehicles are likewise equipped with heavy vehicle event data recorders (HVEDRs) that may trigger during a hard braking or sudden decelerationevent — or when the driver activates a signal to trigger an event to the system. Some heavy commercial vehicleengine manufacturers even provide an additional record of the last stop of the vehicle. Unfortunately, there areno uniform standards as to the information recorded or even the triggering criteria for an event regarding heavy commercial vehicles. HVEDR records oftentimes provide valuable information that assists the forensic engineer inanalyzing collision or failure events. This paper provides the forensic engineer with HVEDR engine manufacturer download coverage and tools needed (as of the presentation of this paper), and explores anomalies in event recording that the forensic engineer should be aware may exist. A case study pertaining to an HVEDR record of a commercial vehicle having a peculiar recording anomaly is presented. This paper outlines the process of how the anomaly was resolved and the process of plotting the sequence of events for courtroom presentation.