The accident data recorder (ADR, German commonly abbr.: UDS, also accident (data) writer) [1] is an independent electronic device that records before, during, and after a traffic accident relevant data and thus resembles a flight recorder.
It can be installed in motor vehicles (cars, trucks, buses, motorcycles, trams, and special vehicles) on a voluntary basis in order to obtain more accurate information about the events in an accident. In some countries there are regulations for mandatory [2] installation in different vehicles. The accident data recorder constantly records various data of the vehicle (such as speed, direction of travel, longitudinal and transverse vehicle acceleration, status of the lights, turn signals and braking, etc.) and records them for some time before they are automatically cleared.
In the case of an accident (this is detected by a strong acceleration of the vehicle as a result of an impulse), certain periods of time (usually in the two-digit seconds range) remain permanently stored before and after an event. This makes it much easier to reconstruct events after an accident, so that if necessary the question of fault can be clarified.
Many vehicles of authorities (such as police or ambulance) are equipped with them, as it often comes to assist with disputes that pertain to collisions during high priority calls as well as compliance with applicable laws and regulations. A side effect of vehicles equipped with UDS is that drivers behave more cautiously on the road. [3] [4] According to a survey by the EU Transport Commission, UDS users experienced a 20 to 30 percent decline in traffic accidents. [5]
The accident data recorder is often used by experts or institutions in crash tests as a measuring device. [6]
The installation (also later) costs about 700 euros [7] and can lead to a deduction for some insurance policies. The accident data recorder can be read by an expert via interface cable. The accident data recorder (older generations) has a switch with which the driver can delete the stored data immediately after an accident so as not to burden himself with the later question of guilt. However, this feature may be disabled, for example for use in company vehicles. [8]
Accident data recorders work to measure the accelerations, depending on the equipment in two or three spatial directions, with micromechanical sensors. Often several sensor systems with different resolutions are used in order to be able to log both the driving dynamic processes and the collision dynamics. Higher-class systems also offer a possibility for measuring the rotational movements as well as the vehicle speed as well as highly specific measurements to the amount of pressure applied on different controls. The latter can e.g. be calculated from the signal of the vehicle's wheel speed sensor. The recording of any signals that are available on the vehicle's own CAN bus, is possible with higher-class devices as well as the detection of a GPS signal for position and speed determination. Depending on the manufacturer, about 20 to 30 s are recorded before and 10 to 15 s after an event.
Are known today (as of 2018) in the German-speaking countries essentially two suitable for retrofitting accident data recorder. Blacktrack Ltd. offers a low-cost solution, which is mainly used by the insurance industry (e.g. AXA Winterthur in Switzerland). By contrast, the UDS-AT developed by the company consortium Peter Systemtechnik GmbH and Kast GmbH offers extended possibilities of recording and integration into a vehicle. [9]
Residual path recording devices (RAG) from Mobatime AG are external devices that rely on existing on-board signals (distance, speed, operating states of status inputs) and store them in a ring buffer for at least the last 12 km. [10] In contrast to an accident data recorder, they do not have their own measuring sensors.
In The US, The legal landscape concerning EDRs and ADRs involves an interplay of constitutional principles, particularly the Fourth Amendment's protections against unreasonable searches and seizures. Notably, legal precedents have established exceptions for vehicles, allowing law enforcement to conduct searches without a warrant if probable cause exists. This precedent has been cited in debates regarding the warrantless access of data stored in ADRs.
Recent Supreme Court cases, notably Riley v. California and Carpenter v. U.S., have extended Fourth Amendment protections to digital data, including cell phone information and location data. However, the direct application of these rulings to ADRs remains unclear, contributing to a disparity in legal standards regarding the privacy of car data.
Statutory regulations, such as the Electronic Communications Privacy Act (ECPA), have provided limited protections to third-party-held data, raising questions about their applicability to car manufacturers and ADRs specifically.
Several states have enacted laws supplementing federal regulations to safeguard car data, although the consistency and effectiveness of these measures vary across jurisdictions. [11]
Ongoing Efforts such as the Driver Privacy Act (DPA) and other safeguards aim to regulate access to black box information in vehicles. However, the uniformity in mandating warrants for data access remains a subject of debate and potential future legislative action.
Many states have applicable statutes in which having a self-deletion switch on such a device could be considered tampering with evidence. This is yet to be brought up in any current caselaw as the ADRs that are equipped with such a device are not commonplace in the US.
Reading out the data of an accident data recorder requires special software.
The evaluation and interpretation of measurement data of a traffic accident require special knowledge in the areas of vehicle dynamics, accident reconstruction, metrology and last but not least the accident data storage technology itself. For UDS there is a separate order area for expert witnesses in Germany. [12]
The picture on the right shows the (unprocessed) data curves of a real accident recorded with a UDS. The measured accelerations, the speed and various status channels are plotted over time. It can be seen, for example, that vehicle special signals were switched on prior to the collision and the driver was previously still applying the brake.
The nowadays known accident data recorder was invented by Mannesmann Kienzle GmbH, which applied for a patent in 1992. [13] [14] The development began in Germany in the early 1980s with the two companies MBB and Kienzle, who pursued different concepts. In general, the black box was taken as a model, which was developed in the early 1950s in Australia by David Warren. Already in 1973, General Motors applied for a patent for a "vehicle crash recorder". [15] Mannesmann Kienzle delivered the first accident data recorder in early 1993. [16]
In motorsport, accident data recorders (ADR) must be used in various series as specified by the FIA. Starting with the 2015 season, the use of an ADR in the Formula 4 championship was compulsory. [17] In the higher series, the use has been mandatory for some time. In addition to the data of the acceleration sensors mounted on the vehicle, the loads on the driver are also measured with an in-ear accelerometer. [18]
Due to the higher speeds in formula sports compared to road traffic, the sensors have a measuring range of ± 150 g with a resolution of 0.1 g. 2 s are recorded before an event. With an event duration of 30 s, 10 events can be stored. [19]
Both in a flight recorder and in a UDS, the constantly recorded data runs in a ring buffer. However, the flight recorder usually records for longer periods of 17 to 25 hours. In contrast, the UDS only saves a few seconds before and after an event is triggered (e.g. collision) permanently.
The term drive data recorder is generally understood to mean a continuous and permanently available recording of data and signals during the operation of a vehicle, independently of an accident. Such systems are often used in locomotives or trams. Often, however, an electronic logbook is referred to as drive data recorder. Dashcams are sometimes referred to as drive data recorder or video event data recorder (VEDR).
A so-called Event Data Recorder (EDR) is not an accident data recorder in the sense of an autonomous, more or less vehicle-independent device, since an EDR is usually an additional electronic module in an existing control device (e.g. from the Airbag) in a car. EDRs rely exclusively on on-board signals, while UDS have their own inertial sensors. Vehicles with airbag systems store accident-relevant data (impact accelerations, belt buckle conditions, seat positions, trip times) in the internal memory of the tripping electronics. However, the data size varies depending on the manufacturer and only extends over a few seconds or fractions. NHTSA regulations call for uniform data sets for all systems manufactured from 2010 onwards.
Telemetry is the in situ collection of measurements or other data at remote points and their automatic transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Greek roots tele, 'remote', and metron, 'measure'. Systems that need external instructions and data to operate require the counterpart of telemetry: telecommand.
A controller area network (CAN) is a vehicle bus standard designed to enable efficient communication primarily between electronic control units (ECUs). Originally developed to reduce the complexity and cost of electrical wiring in automobiles through multiplexing, the CAN bus protocol has since been adopted in various other contexts. This broadcast-based, message-oriented protocol ensures data integrity and prioritization through a process called arbitration, allowing the highest priority device to continue transmitting if multiple devices attempt to send data simultaneously, while others back off. Its reliability is enhanced by differential signaling, which mitigates electrical noise. Common versions of the CAN protocol include CAN 2.0, CAN FD, and CAN XL which vary in their data rate capabilities and maximum data payload sizes.
A tachometer is an instrument measuring the rotation speed of a shaft or disk, as in a motor or other machine. The device usually displays the revolutions per minute (RPM) on a calibrated analogue dial, but digital displays are increasingly common.
An accelerometer is a device that measures the proper acceleration of an object. Proper acceleration is the acceleration of the object relative to an observer who is in free fall. Proper acceleration is different from coordinate acceleration, which is acceleration with respect to a given coordinate system, which may or may not be accelerating. For example, an accelerometer at rest on the surface of the Earth will measure an acceleration due to Earth's gravity straight upwards of about g ≈ 9.81 m/s2. By contrast, an accelerometer that is in free fall will measure zero acceleration.
Advanced driver-assistance systems (ADAS) are technologies that assist drivers with the safe operation of a vehicle. Through a human-machine interface, ADAS increase car and road safety. ADAS use automated technology, such as sensors and cameras, to detect nearby obstacles or driver errors, and respond accordingly. ADAS can enable various levels of autonomous driving.
A data logger is an electronic device that records data over time or about location either with a built-in instrument or sensor or via external instruments and sensors. Increasingly, but not entirely, they are based on a digital processor, and called digital data loggers (DDL). They generally are small, battery-powered, portable, and equipped with a microprocessor, internal memory for data storage, and sensors. Some data loggers interface with a personal computer and use software to activate the data logger and view and analyze the collected data, while others have a local interface device and can be used as a stand-alone device.
Electronic throttle control (ETC) is an automobile technology that uses electronics to replace the traditional mechanical linkages between the driver's input such as a foot pedal to the vehicle's throttle mechanism which regulates speed or acceleration. This concept is often called drive by wire, and sometimes called accelerate-by-wire or throttle-by-wire,.
On-board diagnostics (OBD) is a term referring to a vehicle's self-diagnostic and reporting capability. In the United States, this capability is a requirement to comply with federal emissions standards to detect failures that may increase the vehicle tailpipe emissions to more than 150% of the standard to which it was originally certified.
A train event recorder – also called On-Train Monitoring Recorder (OTMR), On-Train Data Recorder (OTDR), Event Recorder System (ERS), Event Recorder Unit (ERU), or Juridical Recording Unit (JRU) – is a device that records data about the operation of train controls, the performance of the train in response to those controls, and the operation of associated control systems. It is similar in purpose to the flight data recorder or black box used on aircraft.
A voyage data recorder, or VDR, is a data recording system designed for all vessels required to comply with the IMO's International Convention SOLAS Requirements in order to collect data from various sensors on board the vessel. It then digitizes, compresses and stores this information in an externally mounted protective storage unit. The protective storage unit is a tamper-proof unit designed to withstand the extreme shock, impact, pressure and heat, which could be associated with a marine incident.
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, 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.
Traffic collision reconstruction is the process of investigating, analyzing, and drawing conclusions about the causes and events during a vehicle collision. Reconstructionists conduct collision analysis and reconstruction to identify the cause of a collision and contributing factors including the role of the driver(s), vehicle(s), roadway and general environment. Physics and engineering principles are the basis for these analyses and may involve the use of software for calculations and simulations. Collision reconstruction is sometimes used as the basis of expert witness testimony at trials. Collision reconstructions are performed in cases involving fatalities or personal injury. Results from collision reconstructions are also sometimes used for making roads and highways safer, as well as improving safety aspects of motor vehicle designs. Reconstructions are typically conducted by forensic engineers, specialized units in law enforcement agencies, or private consultants.
The Air Cushion Restraint System (ACRS), was developed by General Motors in the early 1970s, and consisted of both a driver's and passenger's side air bag, along with a lap belt and status indicator light. The system was first installed in a test fleet of 1,000 1973 Chevrolet Impala 4-door sedans, painted in a unique green color. The exterior of these Impalas were identical to regular 1973 production models, but used a 1974-style Oldsmobile instrument panel and brand-new steering wheel design. The chassis of these cars were reinforced, and each Impala was equipped with a high-performance 350 cubic-inch V8 engine, the same one used in the Corvette.
Direct TPMS, or direct tire pressure monitoring systems refers to the use of a pressure sensor directly mounted on the wheels or tires of a vehicle. The pressure inside the tire is measured using a pressure transducer with the pressure information being subsequently sent to the vehicle to warn the driver of under or over inflation of a tire. The pressure information is commonly transmitted to the vehicle using radio frequency (RF) technology, though systems using mechanical, electrical or magnetic methods have been used over recent years.
In transportation, collision avoidance is the maintenance of systems and practices designed to prevent vehicles from colliding with each other. They perceive the environment with sensors and prevent collisions using the data collected from the sensors. Collision avoidance is used in autonomous vehicles, aviation, trains and water transport. Examples of collision avoidance include:
In 1986, the GM Motorsports group asked Delco Electronics Corporation (December), a subsidiary of GM Hughes Electronics if an electronic engine management system could be developed for the Chevy Indy V8 engines used in the CART open-wheel race series. Delco Electronics had been supplying all GM automobiles sold in the US with Engine Control Modules (ECMs) since 1981 when the US Clean Air Act required 3-way catalytic converters and controlled air-fuel ratios. The production ECMs were becoming more complex, and were becoming powertrain controllers controlling the transmission, spark timing, Idle speed, as well as air-fuel intake mixtures.
An inertial navigation system is a navigation device that uses motion sensors (accelerometers), rotation sensors (gyroscopes) and a computer to continuously calculate by dead reckoning the position, the orientation, and the velocity of a moving object without the need for external references. Often the inertial sensors are supplemented by a barometric altimeter and sometimes by magnetic sensors (magnetometers) and/or speed measuring devices. INSs are used on mobile robots and on vehicles such as ships, aircraft, submarines, guided missiles, and spacecraft. Older INS systems generally used an inertial platform as their mounting point to the vehicle and the terms are sometimes considered synonymous.
Sudden unintended acceleration (SUA) is the unintended, unexpected, uncontrolled acceleration of a vehicle, often accompanied by an apparent loss of braking effectiveness. Such problems may be caused by driver error, mechanical or electrical problems, or some combination of these factors. The US National Highway Traffic Safety Administration estimates 16,000 accidents per year in the United States occur when drivers intend to apply the brake but mistakenly apply the accelerator.
RACELOGIC Ltd is a technology company based in Buckingham, United Kingdom.
A dashboard camera or simply dashcam, also known as car digital video recorder, driving recorder, or event data recorder (EDR), is an onboard camera that continuously records the view through a vehicle's front windscreen and sometimes rear or other windows. Some dashcams include a camera to record the interior of the car in 360 degrees inside camera, usually in a ball form, and can automatically send pictures and video using 4G.