A HRG gyrocompass is a compass and instrument of navigation. It is a new generation of maintenance free instrument.
The HRG gyrocompass is a complete unit, which unlike a conventional compass, has no rotating or other moving parts. It uses Hemispherical Resonant gyroscope, accelerometers and computers to compute True north. It has outstanding reliability. Its Mean Time Between Failure (MTBF) value is a multiple of the MTBF values of fibre optical gyrocompass but also conventional mechanical gyros. The HRG gyrocompass is also immune to severe environmental conditions
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HRG gyrocompass Wikipedia(Text) CC BY-SA