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The VDR (Voyage Data Recorder) is the maritime counterpart to the black boxes used by airlines. The system is typically two-part, comprising an data collection unit that is attached to a protective capsule on deck designed to withstand fire, deep-sea pressure and shock as well as penetration. It is commonly used to record incidents during navigation, but can also provide useful data to analyze the effects of heavy weather and monitoring of performance as well as for crew training.
Up-grading
Many ships equipped with VDR/SVDR equipment meet the bare minimum regulatory requirements However, the crew is encouraged to consider using the equipment for incident investigation or preventive maintenance as well as bridge team training as well as for recording near misses. There are also programs that can dramatically extend the period of duration for which VDR data is available from the current 12 hour minimum and a decision needs to be made on whether or not to upgrade to this.
The system is built around an industrial-grade processor that performs many functions, such as processing and encoding data received from sensors. The capsule is designed to withstand any disaster and keep the data. The key components of the VDR system are a data collection unit that is located on the bridge, a dedicated power source, an interface unit and backup batteries. The unit collects all information from integrated sources such as microphones used to record bridge audio and sends it to a Concentrator, which is where a string of NMEA 0183 sentences is interpreted and then coded to be sent to the final recording media.