What is the definition of FOG?

Stands for fibre-optic gyroscope. A FOG is an optical gyroscope that uses narrowband light waveforms travelling through fibre-optic coils to measure rotation based on the Sagnac effect.

Boreas Axes Systems V4

In the graphic, the FOG is rotating about the Z-axis. During rotation, the phase shift of the light can be seen as a difference in arrival time of the two light beams at the optical receiver. Phase shift in the light occurs only during rotation; once the rotation stops, the light will again be in phase. Note that this is for illustrative purposes only and not necessarily a depiction of the actual technology.

What other terms are related to fibre-optic gyroscope?

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Advanced Navigation’s glossary covers the most common terms and definitions used in inertial navigation systems, acoustic positioning and robotics.

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