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What’s the difference between FOG and RLG?

We provide navigation solutions based on both ring laser gyros (RLG) and fibre optic gyros (FOG). Why not focus on a single technology?

The key components of any inertial navigation solution (INS) are the gyroscopes. The gyroscopes measure rotation and their performance can be directly linked to the overall system performance.
There are different technologies that can be used to create optical gyroscopes and while they all take advantage of the same phenomenon, Sagnac effect, the gyroscope characteristic is very different and lends itself to different applications.

While the RLG is insensitive to e.g. temperature changes and vibrations they have the capability to provide very high performance at a small form factor.

The FOG in contrast is sensitive to temperature and vibrations but can be more cost effective.

Due to the inherently different characteristics, we used RLGs in our highest performing navigation solutions, such as SPRINT-Nav and SPRINT, which is aimed at survey applications and autonomous navigation.

FOGs are used in the cost-effective SPRINT-Nav Mini which is aimed at smaller vehicles for inspection work or MCM applications.

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