Spot calibration method of rotary strap-down inertial navigation system with unknown carrier attitude

Abstract

The invention provides a spot calibration method of a rotary strap-down inertial navigation system with unknown carrier attitude. The spot calibration method comprises steps as follows: fastening a fiber-optic gyroscope on a table surface of a dual-shaft indexing mechanism, so that a coordinate system of the gyroscope is ensured to be overlapped with a coordinate system of the indexing mechanism; determining an initial position parameter of the carrier through a GPS (global positioning system) and binding the initial position parameter of the carrier in a computer; collecting data output by the fiber-optic gyroscope and a quartz accelerometer and processing the data; determining horizontal attitude angle of the carrier by utilizing gravity sensing component of the accelerometer; establishing a simple error model of the fiber-optic gyroscope; designing an eight-position indexing scheme by using the dual-shaft indexing mechanism; and processing output at each position of gyroscope module collected by the computer through Matlab to obtain various error parameters of the gyroscope module. A eight-position static calibration method provided by the dual-shaft indexing mechanism disclosed by the invention can be applied to calculating each error coefficient of the fiber-optic gyroscope accurately, thereby short-time and high-precision calibration work of the fiber-optic gyroscope under a condition that the carrier attitude is unknown are accomplished.

Description

(1) Technical field [0001] The present invention relates to a measurement method, in particular to a field calibration method for a rotating strapdown inertial navigation system with an unknown carrier attitude (2) Background technology [0002] Fiber optic gyroscope has been rapidly developed and applied in the field of inertial devices due to its advantages of large dynamic range, high precision, fast start-up and flexible system design. The calibration technology of the fiber optic gyroscope is to establish its error mathematical model, use certain experiments to determine the model coefficients, and then use software algorithms to eliminate errors. At present, the calibration technology of fiber optic gyroscope is relatively mature. According to the different calibration places, it can be divided into in-field calibration and out-field calibration. These are two different stages of calibration. In-field calibration is the basis of out-field calibration. Infield calibrat...

AI Technical Summary

Problems solved by technology

During on-site calibration, since there is no precision turntable as a test reference, it is difficult to precisely orient the SINS, so the traditional turntable-based multi-position test and rate test cannot be implemented

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