Press Releases
July 2018

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Mecanica Scientific Services Corp. Wins Feasibility Study for Event Data Recorders Contract with Canadian Government
April 2017

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Timing and Synchronization of the Event Data Recorded by the Electronic Control Modules of Commercial Motor Vehicles - DDEC V
SAE International
April 2013

John Steiner ​CEO / Principal Scientist
David P. Mechanical Engineer
Timothy C. Principal Engineer
Heath Spivey Professional Engineer

This research demonstrated the timing and latency of various data elements that may be recorded within the EDR function of a Detroit Diesel electronic control module.
Driver Response to Roadway Intrusion at Night
European Association of Accident Research and Analysis

Author:John Grindey
Co-Author(s):Christopher Armstrong, Stein Husher, John C. Steiner, Michael Varat

A dark object in the path of a vehicle at night is a challenge for a driver to detect and respond to. Many factors influence the driver’s ability to perform this task. These include: roadway configuration, environmental conditions, driver physiology and object characteristics. This study analyzes the relative distance between a driver discerning an object in the roadway during nighttime conditions and the driver‘s response.

This study involves 25 un-alerted, but attentive drivers approaching a dark object in their path at speeds ranging from 63 to 113 kph (39 to 70 mph). The test vehicle was driven on a closed course with drivers participating in an unrelated night driving exercise. During the exercise a dark object was placed in the path of the subject driver’s vehicle. The driver‘s responses, response times and distances from the object were monitored and reported.
Event Data Recorders, A Decade of Innovation
Society of Automotive Engineers (SAE)
April 2008

Author: H. Clay Gabler

Co-Author(s): John A. Hinch & John Steiner

This book contains 28 landmark papers, providing a comprehensive look at event data recorder (EDR) technology for cars, light trucks, and heavy vehicles. By collecting EDR data, vehicle safety trends can be established, providing car companies, researchers, and regulators with science-based methods to better understand vehicle crashes.

In addition to classic and cutting-edge papers, the book features insightful materials on the new National Highway Traffic Safety Administration (NHTSA) Final Rule on Event Data Recorders (49 CFR, Part 563), including the rule itself, a summary, and the response to petitions for reconsideration.
Bulb Usage Analysis for LED-Type Automotive Lighting
SAE Paper No. 2003-01-0892; SAE World Congress 2003; Detroit, MI

Author: John Steiner

The technology of exterior automotive lighting is undergoing the first major change in a half-century. Manufacturers of road vehicles, including motorcycles, are increasingly using Light Emitting Diode (LED) lamps in the place of incandescent light bulbs in exterior lighting applications, including brake lamps, turn signals and parking lamps.

Analysis of incandescent bulb filaments has been well documented ( References 2 , 3 , 4 , 5 , 6 and 7 ), and is a well-accepted practice in accident analysis. But little appears to be known about how, or even if, LED lamps respond to the forces of acceleration or direct-impact events to provide a “record” of the state of the lamp at the moment of an accident event. This project examined the responses of lighted and unlighted LEDs to both acceleration and direct impact events for indications of their state of operation when damaged.
Event Data Recorder Pre-Crash Data Sources for General Motors Vehicles
ASME Paper No. IMECE2003-41812
ASME International Mechanical Engineering Congress 2003; Washington, D.C.

Author: John Steiner

The Event Data Recorder (EDR) found in some 1994 model year and newer General Motors (GM) passenger vehicles has the ability to record up to five seconds of pre-crash data. Such as vehicle speed, engine speed, percent throttle application and brake application before a predetermined deceleration event as well as crash data such as delta-v’s. The pre-crash and crash data can be downloaded by properly equipped and trained personnel using the Vetronix Crash Data Retrieval (CDR) System. However, this data must not simply be taken at face value; the Accident Analyst must be aware of the nature of the differing types and sources of the data, and must ensure that the systems supplying the data was in a normal operating mode and not in a default mode or in a “limp home” mode due to pre existing problems. This paper discusses how different environments and scenarios that the vehicle can be operated in changes how the vehicle will respond to driver inputs thus effecting pre-crash data recorded by the Event Data Recorder.
Modeling of Truck-Car Sideswipe Collisions Using Lug Patterns
SAE Paper No. 2008-01-0179
SAE World Congress 2008; Detroit, MI

Author: John Steiner

Vehicle to vehicle sideswipe collisions may involve contact between a vehicle body and a contacting vehicle's rotating wheels, tires and lug nuts. During a sideswipe collision between a truck and an automobile it is not uncommon to see lug marks in the shape of consecutive damage loops or strikes on the side of the impacted vehicle. The damage loops or strikes are generated by the protruding lug nuts of the truck wheel as it passes by the impacted vehicle at a shallow angle. Additionally, rubber transfers due to contact with the tire sidewall and metal scraping from the wheel rim also leave distinctive shapes on the sides of the contacted vehicle body. The tire, rim, lug nut markings and associated damage manifest themselves as a special case of the epitrochoid and can be geometrically and mathematically described. Presented is a derivation of the equations that govern the lug, rim and tire positions and relative motions. The equations are derived in terms of the speeds of the two impacting vehicles as well as the relevant geometry. A spreadsheet implementation of the equations facilitates their application to accident reconstruction. Staged collision testing using instrumented vehicles at known speeds was conducted. The mathematically derived shapes were compared to the staged collision test contact patterns. The application to transportation accident reconstruction is discussed.
Forensic Evidence Relating to Motorcycle Pre-Crash Maneuvers
7th International IFZ Motorcycle Conference
Cologne, Germany, 2008

Co-Author(s): Stein E.Husher, Michael S. Varat, Christopher D. Armstrong, John C. Steiner

When analyzing collisions involving powered two wheelers, often, the determination of pre-crash maneuvers is sought. These pre-crash maneuvers generally involve braking and cornering which can leave evidence on the roadway or on the tire. This roadway evidence, when present, generally consists of tire marks which can result from both braking and steering. Observed vehicle evidence from precrash maneuvers often consists of surface modifications on the tires which can provide information relating to the severity of the braking and cornering motions. The present research is undertaken to evaluate observable scene and vehicle evidence based on documented motorcycle dynamics during pre-crash braking and steering. Case studies from real world collisions are presented. Braking test data is presented and roadway and vehicle evidence is described. A series of riding tests were performed and the vehicle dynamics and associated tire evidence was documented. It was found that if roadway evidence from some pre-crash maneuvers is overlooked by the on-scene investigator, careful analysis of the motorcycle tires can yield valuable information relating to the severity of the maneuvers performed. Additionally, motorcyclist utilization of available vehicle performance may be evident from the condition of the motorcycle tires at the post event analysis. This careful tire documentation, as a crash research technique, provides valuable information not available from other sources.
Data Sources and Analysis of a Heavy Vehicle Event Data Recorder – V-MAC III
SAE Paper No. 2009-01-0881; SAE World Congress 2009; Detroit, MI

Co-Author(s): John Steiner, Timothy M. Cheek, Scott H. Hinkson

Heavy trucks can have the capability to record vehicle status and performance data. In many applications, this capability is intrinsic to the powerplant’s electronic controls. However little information has been published regarding Heavy Vehicle Event Data Recorder (HVEDR) data obtained from Mack trucks equipped with the V-MAC vehicle electronic control units. This study is focused on data from Mack trucks and the influence of wheel slip on the HVEDR-reported vehicle speed. Additionally, the influence of variables such as initial speed and loaded condition are discussed. A late model Class 8 Mack was instrumented with a calibrated data acquisition package (DAQ) and put through a series of tests so that the HVEDR data could be compared to the data collected by the DAQ.
Unfalldatenspeicher in Nordamerika (Data Recorders in North America)
VKU: Verkehrsunfall und Fahrzeugtechnik; January 2010

Author: John Steiner

Aus technischer Sicht ist die Aufzeichnung unfallrelevanter Daten im Kraftfahrzeug mittels Unfalldatenspeicher UDS schon lange möglich. Solange der Einbau in Fahrzeuge in Europa nicht obligatorisch ist, fordern Unfallanalytiker, wenigstens die von Herstellern in Fehlerspeichern gesammelten Daten nutzen zu können. Da es die Datenspeicherung in den USA mittels Event Data Recorder EDR schon gibt, beschreibt ein amerikanischer Experte Möglichkeiten und Grenzen der Datennutzung für die Unfallanalyse.
Unfalldatenspeicher für schwere Nutzfahrzeuge in Nordamerika (North American Heavy Vehicle Event Data Recorder (HVEDR)
VKU: Verkehrsunfall und Fahrzeugtechnik; February 2010

Author: John Steiner

Aus technischer Sicht ist die Aufzeichnung unfallrelevanter Daten im Kraftfahrzeug mittels Unfalldatenspeicher UDS schon lange möglich. Solange der Einbau in Fahrzeuge in Europa nicht obligatorisch ist, fordern Unfallanalytiker, wenigstens die von Herstellern in Fehlerspeichern gesammelten Daten nutzen zu können. Da es die Datenspeicherung in den USA mittels Event Data Recorder EDR schon gibt, beschreibt ein amerikanischer Experte Möglichkeiten und Grenzen der Datennutzung für die Unfallanalyse.
Event Data Recorders & Heavy Vehicle Event Data Recorders, the U.S. Experience / Event Data Recorder & Nutzfahrzeug Event Data Recorder – Erfahrungen aus den USA
21. Jahrestagung der Europäischen Vereinigung für Unfallforschung und Unfallanalyse e.V.
21st Annual Congress of the European Association for Accident Research and Analysis
Brașov, Romania; September, 2012

Author: John Steiner

ThEVU 2012 Brasov Steinere introduction of the supplemental inflatable restraint system (airbags) in some North American production vehicles of the mid 1970’s, laid the foundation for the introduction of Event Data Recorders (EDR) in North America. In order to meet more stringent performance and safety requirements, advances in occupant protection systems and engine and emmissions control systems were accomplished with electronics and solid-state devices. The advances in these vehicle sub-systems gives us the ability to easily record data in late model North American light-, medium- and heavy-duty vehicles. This paper is an overview of the history of the North American Event Data Recorder (EDR), Heavy Vehicle Event Data Recorder (HVEDR), and how data from these devices are being used.
Timing and Synchronization of the Event Data Recorded by the Electronic Control Modules of Commercial Motor Vehicles – DDEC V
SAE Paper No. 2013-01-1267
SAE World Congress 2013; Detroit, MI

Co-Author(s): John Steiner, David Plant, Timothy Cheek, Timothy Austin, Michael Farrell, Heath Spivey

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. Several of the monitored parameters were then simultaneously changed through the use of a switch to determine timing between state change, receipt by the ECM, and J1939 CAN broadcast. Testing with the switch that simultaneously changed the states of four of the five monitored parameters established the time lags that exist between when the sourcing signal was generated and when the value for this signal was broadcast on the vehicle's J1939 CAN and reported by the HVEDR function of the DDEC V ECM. Testing with the switch also established that the data reported by the HVEDR function of the DDEC V ECM are asynchronous. Finally, the timing and synchronicity of the Electronic Engine Controller #2 (EEC2) and Cruise Control/Vehicle Speed (CCVS) Application Layer Parameter Group Numbers that are broadcast by the DDEC V ECM over the vehicle's J1939 CAN was determined. In addition, the Electronic Engine Controller #1 (EEC1) Application Layer Parameter Group Number was determined to broadcast asynchronously over the vehicle's J1939 CAN.
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