Event data recorder

Device in some automobiles to record accident information

An event data recorder (EDR), more specifically motor vehicle event data recorder (MVEDR), similar to an accident data recorder, (ADR) sometimes referred to informally as an automotive black box (by analogy with the common nickname for flight recorders), is a device installed in some automobiles to record information related to traffic collisions. In the USA EDRs must meet federal standards, as described within the U. S. Code of Federal Regulations. The term generally refers to a simple, tamper proof, read write memory device. The role of the EDR is limited compared to journey data recorders such as digital tachographs in Europe or electronic logging device in the USA, which may also be referred to as a black box or in vehicle data recorder. In modern diesel trucks, EDRs are triggered by electronically sensed problems in the engine (often called faults), or a sudden change in wheel speed. One or more of these conditions may occur because of an accident. Information from these devices can be collected after a crash and analyzed to help determine what the vehicles were doing before, during and after the crash or event.

In its efforts to establish the uniform scientific crash data needed to make vehicle and highway transportation safer and reduce fatalities, the IEEE launched IEEE 1616 in 2004. It was the first universal standard for MVEDRs, much like those that monitor crashes on aircraft and trains. The new standard specifies minimal performance characteristics for onboard tamper and crash proof memory devices for all types and classes of highway and roadway vehicles. This international protocol will help manufacturers develop what is commonly called "black boxes" for autos, trucks, buses, ambulances, fire trucks and other vehicles. It includes a data dictionary of 86 data elements and covers device survivability. Since 2006, the US has prescribed what data must be recorded in event data recorders, if a vehicle has an event data recorder, in American regulation 49 CFR 563. In March 2021, the new UN Regulation 160 on Event Data Recorders is adopted by the World Forum for Harmonization of Vehicle Regulations.

In the US 49/563.5 regulatory framework, Event data recorder is defined as a a device or function in a vehicle that records the vehicle's dynamic time series data during the time period just prior to a crash event (e. g., vehicle speed vs. time) or during a crash event (e. g., delta V vs. time), intended for retrieval after the crash event. For the purposes of this definition, the event data do not include audio and video data.

Some EDRs continuously record data, overwriting the previous few minutes until a crash stops them, and others are activated by crash like events (such as sudden changes in velocity) and may continue to record until the accident is over, or until the recording time is expired. EDRs may record a wide range of data elements, potentially including whether the brakes were applied, the speed at the time of impact, the steering angle, and whether seat belt circuits were shown as "Buckled" or "Unbuckled" at the time of the crash. Current EDRs store the information internally on an EEPROM until recovered from the module. Some vehicles have communications systems (such as GM's OnStar system) that may transmit some data, such as an alert that the airbags have been deployed, to a remote location. Most EDRs in automobiles and light trucks are part of the restraint system control module, which senses impact accelerations and determines what restraints (airbags and/or seatbelt tensioners) to deploy. After the deployment (or non deployment) decisions are made, and if there is still power available, the data are written to memory. The data downloaded from older EDRs usually contain 6 to 8 pages of information, though many newer systems include many more data elements and require more pages, depending on the make/model/year of the vehicle being evaluated. Depending on the type of EDR, it may contain either a deployment file or a non deployment file or sometimes both, depending on the circumstances of the collisions and the time interval between them, among other things. It is also possible that no data can be recovered from a data recorder. One situation where this might occur is a catastrophic loss of electrical power early in a collision event. In this situation, the power reserve in the restraint system control module capacitors may be completely spent by the deployment of the air bags, leaving insufficient power to write data to the EEPROM. There are other circumstances where a module may fail to record a data file as well. Most EDRs in heavy trucks are part of the engine electronic control module (ECM), which controls fuel injection timing and other functions in modern heavy duty diesel engines. The EDR functions are different for different engine manufacturers, but most recognize engine events such as sudden stops, low oil pressure, or coolant loss. Detroit Diesel, Caterpillar Inc., Mercedes Benz, Mack Trucks, and Cummins engines are among those that may contain this function. When a fault related event occurs, the data is written to memory. When an event triggered by a reduction in wheel speed is sensed, the data that is written to memory can include almost two minutes of data about vehicle speed, brake application, clutch application, and cruise control status. The data can be downloaded later using the computer software and cables for the specific engine involved. These software tools often allow monitoring of the driver hours of service, fuel economy, idle time, average travel speeds, and other information related to the maintenance and operation of the vehicle. Some EDRs only keep track of the car's speed along its length and not the speed going sideways. Analysts generally look at the momentum, energy, and crush damage, and then compare their speed estimates to the number coming out of the EDR to create a complete view of the accident. There are many different patents related to various types of EDR features.

The Eaton Vehicle Onboard Radar (VORAD) Collision Warning System is used by many commercial trucking firms to aid drivers and improve safety. The system includes forward and side radar sensors to detect the presence, proximity and movements of vehicles around the truck to then alert the truck driver. When sensors determine that the truck is closing on a vehicle ahead too quickly or that a nearby vehicle is potentially hazardous, the VORAD system gives the driver both a visual and audible warning. The VORAD system also monitors various parameters of the truck including vehicle speed and turn rate plus the status of vehicle systems and controls. The monitored data is captured and recorded by the VORAD system. This monitored data can be extracted and analyzed in the event of an accident. The recorded data can be used by accident investigators and forensic engineers to show the movement and speed of the host vehicle plus the position and speeds of other vehicles prior to the incident. In accident reconstruction, the VORAD system is a step above the EDR systems in that VORAD monitors other vehicles relative to the host vehicle, while EDR's only record data about the host vehicle.

Event data recorders were introduced to American open wheel championship CART in the 1993 season, and the Formula One World Championship in 1997. Data collected by the recorders was used to improve safety and design factors in race vehicles

Some forensic studies are underway regarding rules and regulations and warn automakers and crash investigators of privacy concerns and unintended use of retrieved EDR data. Beginning in the late 90s light vehicle manufacturers included electronic data recorders (EDR) in most vehicles; they are commonly referred to as 'Black Boxes'. Despite alerts and warnings in their vehicle owner's manual, many drivers are not aware of their vehicle's recording capability. Civil liberty and privacy groups have raised concerns about the implications of data recorders 'spying' on car users, particularly as the issue of 'who owns the data' has not yet been fully resolved, and there has been some controversy over the use of recorded data as evidence in court cases and for insurance claims against the driver of a crashed vehicle. But the use of EDR data in civil and criminal court cases is on the rise as they become more accepted as a source of reliable empirical evidence in accident reconstruction. In the United States, at least 17 states have statutes specific to EDRs. Generally, these state statutes restrict access to the EDR or limit the use of recovered EDR information. The U. S. federal Driver Privacy Act of 2015 was enacted on December 4, 2015. It stated that the owner or lessee of a motor vehicle is the owner of the data collected by the EDR. In order to access that data, an investigator would need to (1) be authorized by a court or judicial or administrative authority, subject to the standards for admission into evidence; (2) obtain the written, electronic or recorded audio consent of the vehicle owner or lessee; (3) be conducting an investigation or inspection authorized by federal law; (4) demonstrate it is necessary to facilitate medical care in response to a car accident; or (5) be conducting traffic safety research, so long as the personal information of the owner/lessee is not disclosed. In Canada, it is considered that there is no expectation of privacy since the information contained in the EDR did not contain "intimate details of the driver’s biological core that could be said to directly compromise his dignity, integrity, and autonomy. ".