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The use of Heavy Vehicle Event Data Recorders (HVEDRs) in collision analysis has been well recognized in past research. Numerous publications have been presented illustrating data accuracy both in normal operating conditions as well as under emergency braking conditions. These data recording devices are generally incorporated into Electronic Control Modules (ECMs) for engines or Electronic Control Units (ECUs) for other vehicular components such as the Anti-Lock Brake System. Other research has looked at after-market recorders, including publically-available Global Positioning System (GPS) devices and fleet management tools such as Qualcomm. In 2009, the National Fire Protection Association (NFPA) incorporated a Vehicle Data Recorder (VDR) component into their Standard for Automotive Fire Apparatus. The purpose of this was to “…capture data that can be used to promote safe driving and riding practices.” The Standard requires minimum data elements, recording times, and sample rates.

It is well recognized that Heavy Vehicle Event Data Recorder (HVEDR) technology has been incorporated in the Electronic Control Modules (ECMs) on many on-highway commercial motor vehicles. The dynamic time-series data recorded by these HVEDRs typically include vehicle speed, engine speed, brake and clutch pedal status, and accelerator pedal position. With specific respect to Detroit Diesel ECMs, data are recorded surrounding certain events at a rate of 1.0 Hz. In this research, controlled testing was conducted to determine the time differences between the values being generated by the sourcing sensors and the interpreted data being broadcast on the vehicle's SAE J1939 controller area network (CAN). To accomplish this, raw sensor data as provided to the ECM was monitored, as were the subsequent J1939 CAN transmissions from the ECM.

Modern heavy vehicles may be equipped with an Advanced Driver Assistance System (ADAS) designed to increase highway safety. Depending on the vehicle or manufacturer, these systems may detect objects in a driver’s blind spot, provide an alert when the ADAS determines that the vehicle is leaving its lane of travel without the use of a turn signal, or notify the driver when certain road signs are detected. ADASs also include adaptive cruise control, which adjusts the vehicle’s set cruise speed to maintain a safe following distance when a slower vehicle is detected ahead of the truck. In addition, the ADAS may have a Collision Mitigation System (CMS) component that is designed to help drivers respond to roadway situations and reduce the severity of crashes. CMSs typically use radar or a combination of radar and optical technologies to detect objects such as vehicles or pedestrians in the vehicle’s path.

For model year 2018, Freightliner introduced the New Cascadia model to their lineup of Class 8 trucks. Testing of the Freightliner New Cascadia with Detroit Diesel engines was conducted to evaluate the accuracy of the reported event data contained in the engine Electronic Control Units (ECUs) for these trucks. The testing showed that there are occurrences in DDEC Reports, specifically in the Last Stop Record and Hard Braking event data, when the time between successive event data points was two seconds rather than the reported one second interval. The occurrence of the two-second anomaly was not always present in a Last Stop Record or Hard Braking event. When the two-second anomaly was present in the event data, it occurred randomly and no pattern to when this anomaly occurs was determined. No method was found to be able to detect the presence of this anomaly from the review of a Last Stop Record or Hard Braking event.

Electronic control units of Bendix® ABS/ESC and Collision Mitigation Systems have the capability to record event data in the ABS/ESC control unit. Bendix refers to this event data recording functionality as the Bendix Data Recorder (BDR). This paper presents an overview of the BDR functionality and examines the range and resolution of data elements, the synchronicity or timing of the recorded data, and application of the data for use in analyzing crashes. Various tests were performed using trucks equipped with Bendix® Wingman® Fusion™ and were conducted in a manner to trigger BDR records. BDR data was compared to data collected from the J1939 CAN Bus and from Racelogic VBOX data loggers.