1.The use of gyroscopic technology
For more than 100 years, gyroscopic technology has been used to aid navigation in a variety of applications. Mechanical gyroscopes were relied upon for about 60 years until the invention of the ring laser gyroscope in the 1960s. However, it wasn't until the 1970s that fiber optic gyroscopes were developed, implemented, and became popular in a wide range of applications from submarines to spacecraft.
The goal of any gyroscope is to measure the angular rotation rate on any single axis. This is critical for determining the pitch, roll, and yaw angles in a system that requires reliable navigation information to function properly. Imagine a plane taking off, a NASA rocket diving, or a missile finding its target. Gyroscopes for such applications measure the angular rotation rate of each vehicle. This critical information is sent downstream to control and stabilize the vehicle. Each gyroscope provides this information with varying degrees of reliability and accuracy, so how does a fiber optic gyroscope differ from other gyroscopes?

2.Optical fiber technology https://www.ericcointernational.com/gyroscope/fiber-optic-gyroscope
As the name suggests, fiber optic gyroscopes use fiber optics to perform their work. Fiber optics are made of glass and are used in many applications to transmit light from one point to another. Fiber optic cables are commonly used in telecommunications such as telephones and the Internet, and are extremely fast and reliable.

FOG technology

In a fiber optic gyroscope, this method of light transmission is not used to transmit information elsewhere, but is tightly wound in an independent closed loop within the gyroscope. This allows the fiber optic gyroscope to take advantage of the "Sagnac effect."

3.Sagnac effect
This phenomenon, discovered by French physicist Georges Sagnac, is at the heart of how every fiber optic gyroscope works.
Inside the gyroscope, the laser is used to send two separate beams of light through an optical fiber. Each beam travels in the opposite direction, propagating the entire length of the fiber, up to 5 kilometers. Each beam then returns to the light detector, recording its travel time.
Take an international flight at cruising altitude. The aircraft is stable, flying straight, level, with no rotation changes.
When there is no rotation change in the aircraft, the beam returns to the detector at the same time. In this case, there is no delay or "phase shift" between each beam. The aircraft was detected as stable and did not undergo any rotation rate around any given axis.
However, when the plane turns, Sagnac will come into full play. When the aircraft turns to the right, the fiber optic gyroscope dedicated to the rolling shaft will experience an arrival delay between the two beams. As it rotates, the distance each beam must travel changes.
When the detector is slightly closer to the traveling beam, the light traveling against the direction of rotation will return first. In this example, the beam propagating to the left will return first. Similarly, a beam traveling to the right will take longer. The phase shift between each beam is detected as a rotational change. This critical information can then be sent downstream to an aircraft, spacecraft, submarine or missile to stabilize it. This happens at a rate of hundreds of times per second, providing very precise measurements.

4.Fiber optic gyroscope calibration
As with any gyroscope, error sources, deviations, and noise must be carefully considered and corrected. During manufacturing, fiber optic gyroscopes are calibrated to correct for several potential sources of error that can be introduced by the gyroscope itself or the environment. When calibrated, fiber optic gyroscopes provide a very high level of performance.
Why use fiber optic gyroscopes?
Fiber optic gyroscopes have become ubiquitous in many applications, with several attractive properties. They remain reliable in harsh environments with intense vibration, have no moving parts, strike a good balance between price and high performance, and can last a long run.

5.Summary
Ericco developed fiber optic gyroscope ER-FOG-851, ER-FOG-910, low cost, good performance, can be widely used in optical pod/flight control level, INS/IMU, platform stabilization device, positioning system, north finder, high precision measurement/navigation system and servo system, if you are interested in learning more, Please feel free to contact us.