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SR 2100
Fiber-Optic Gyrocompass & Attitude Reference System

And then there was light in the future of the gyrocompass...

The new SR 2100 Fiber-Optic Gyrocompass is the first solid-state, fully electronic digital gyrocompass system for marine application in strapdown technology designed for integrated bridges and advanced high-speed vessels.

The fundamental principle of the fiber-optic gyrocompass is the invariance of the speed of light and the so-called Sagnac effect. Here, a fiber-optic coil is used as a very sensitive rate sensor which is capable of measuring the speed of rotation of the earth. A combination of three such fiber-optic coils (gyroscopes) and two electronic level sensors is able to determine the direction of true north. From the three rate of turn signals and the information from the electronic level sensors a complex Kalman filter computes the direction of the rotation of the earth from which geographical north is derived.

Designed in strapdown technology, the fiber-optic gyrocompass is attached directly to the vessel, eliminating the use of a gimbal system. This arrangement supplies heading information and also roll, pitch and rate of turn about all three axes.

The fiber-optic gyrocompass can also be used as a sensor for stabilizer systems not only on merchant marine vessels but also on hydrofoils and catamarans. The extremely short settling time of only 30 minutes will be of great advantage for fast ferries.

The very high dynamic accuracy coupled with the absence of north speed error will much increase the safety of all vessels, particularly so that of high-speed craft at high latitudes during frequent maneuvers at high speed.

The fiber-optic gyrocompass is a complete solid-state design with no rotating or other moving parts. It has very high reliability (MTBF) and no maintenance requirements during its service life. In addition to the sensor unit, a basic SR 2100 system comprises a control and display unit, and an interface and power supply unit. Analogue and digital display units and other peripheral equipment are supplied with output data through serial interfaces. It is also possible to add to the system a second gyrocompass (of the conventional type as a back-up for example) and a transmitting magnetic compass system (Flux gate).

Fiber-Optic Gyrocompass and Attitude Reference Sensor Unit (without cover)
1. Navigation processor and power supply
2, 3, 5. Fiber-optic gyroscope z-axis, x-axis and y-axis
4. Electronic level sensors


  • No moving parts
  • Solid-state technology
  • No maintenance during service life
  • High dynamic accuracy
  • Short settling time
  • Heading, roll, pitch and rate sensor
  • Meets all IMO recommendations including high- speed code
  • High mean time between failure (MTBF)
  • Compact, low-weight design
  • Low power consumption
  • Data transmission via serial interface
  • NMEA 0183 FAST output
  • RS 422 SUPER FAST output
  • Second gyrocompass and magnetic compass input
  • All repeater compasses self-aligning via serial interface
  • Additional analogue outputs for all rate of turn signals
  • Compass monitor and heading selector function to DNV-W1
  • Automatic emergency power changeover to GMDSS
  • Independent, short-circuit proof repeater outputs
  • Built-in test equipment
  • Basic system comprises only three units: Sensor Unit, Control and Display Unit and Interface and Power Supply Unit

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