Fiber optic gyro, or FOG, is a high precision instrument using optical fiber technology. It works intuitively, like "dancing" light in a fiber. When light travels through the fiber, the propagation path in it also changes if the fiber rotates. By accurately measuring this change, the optical fiber gyro can calculate the rotation speed and direction of the optical fiber. The key of fiber optic gyro lies in its high-precision optical system and electronic signal processing system. The optical system ensures that the light travels stably through the optical fiber, while the electronic system is responsible for receiving and processing the optical signals to obtain accurate angular velocity data. Due to its high sensitivity, rapid response and long-term stability, FFG has been widely used in aviation, aerospace, navigation and other fields, providing an important means of angular velocity measurement for navigation and control systems.