Research And Engineering Implementation On Calibration Methods For Fiber Strapdown Inertial Measurement Unit

SINS is a new active cutting edge technology involving many academic areas. Its emergence and development represents a new direction of the modern inertial technology. SINS connect the inertial sensitive devices (gyroscope and acceleration meter) to its carrier rigidly. It determines the carrier’s attitude, azimuth, position and velocity by using the standard direction and the initial position of the inertial sensitive devices. In the SINS, there is the navigation computer to achieve the stable platform functionality, i.e. use the "digital platform instead of the tangible platform in the platform system. The advantages include better functionality, less response time, high reliability, small volume, light weight and cheap. Therefore, it gradually replaces the platform inertial navigation system in many areas. As the development of technology, the optical fiber gyro can be batch produced. The optical fiber strapdown inertial measurement devices enter the engineering application stage.The most important specification to measure an inertial navigation system is the navigation accuracy. No doubt, the accuracy of an inertial navigation system mainly depends on the accuracy level of the inertial devices. It is an effective way to improve the navigation accuracy by calibrating the error coefficients of the inertial devices and compensating using software.A testing system is required to calibrate and compensate the error of the optical fiber inertial measurement devices. This paper introduces the composition of the testing system and demonstrates the theory of the independent calibration method, acceleration meter and the input/output model of the optical fiber gyro. This paper also establishes the position and speed calibration solutions, the temperature calibration and compensation approaches as well as the automatic calibration.