With commercial availability of the Bosch Crash Data Retrieval Tool (CDR), the information stored in vehicle Event Data Recorders (EDRs) has increasingly been used to supplement traditional traffic crash data collection and reconstruction methods, allowing enhanced confidence levels in transportation safety research.
The objective of this study was to assess the accuracy and reliability of EDR data images obtained with the Bosch CDR tool by comparing them to a known crash impulse. Multiple EDRs and necessary sensor arrays were mounted on a HYGE™ acceleration-type crash simulation sled system at various orientations representing different principal direction of force (PDOF) angles and subjected to controlled “crash” impulses, simulating a “deployment event” (DE) and triggering data to be saved in the EDRs. The data included in each EDR's CDR report was compared to the known conditions of the impulse. In addition to direct comparison of longitudinal and lateral delta-Vs, an analysis was performed of the possibility of accurately reconstructing the known total impulse magnitude (resultant delta-V) and the known PDOF angle from the combined longitudinal and lateral CDR record.
The maximum percentage delta-V error magnitude observed was less than the 10 percent limit required by 49 CFR Part 563, and the average error magnitude for each EDR ranged from 0.3% to 4.3%.  The maximum resultant delta-V error magnitude was less than 3%, and the maximum apparent PDOF angle error magnitude was 2.0 degrees.