vehicle data

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.

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