Hull Deformation Measurement Method Based on Time Delay Compensation

Abstract

The invention provides a method for measuring hull deformation based on time delay compensation. First, two sets of fiber optic gyroscopes are installed at fixed positions on the hull, and the deformation angle of the hull is obtained. Then calculate the conversion relationship between the two coordinate systems and finally get the output angular velocity difference. According to the time delay in the actual system, the real angular velocity relationship between the two fiber optic gyroscopes can be obtained. Finally, the gyro drift is introduced to construct the measurement equation of Kalman filter, the mathematical model of gyro drift and hull deformation angle and the state equation of Kalman filter are established, and the angular rate output by the gyro is used as the observation input to estimate the deformation angle. This method provides a compensation method for the time delay problem faced by the FGU-based hull deformation measurement technology in the actual ship measurement application, thereby reducing the measurement error and improving the measurement accuracy. It is simple and practical, and the compensation effect is obvious, which is beneficial to the hull deformation. Application of measurement technology.

Description

technical field [0001] The invention relates to a time delay compensation method, in particular to a time delay compensation method in the hull deformation measurement technology based on FGU (FiberGyroUnit, fiber optic inertial measurement unit). Background technique [0002] When a ship sails at sea, it is affected by many factors, and the deck of the ship will have non-negligible deformation. This makes the attitude sent by MINS (Master Inertial Navigation) to the shipborne system and other points only at the MINS, not the carrier coordinate system of each point relative to the local coordinate system of the navigation coordinate system. The distance between MINS and the local position The attitude difference will seriously affect the accuracy of the shipboard system. [0003] Compared with the measurement methods based on structural mechanics such as the grating method and the dual-frequency polarized light method, the hull deformation measurement method based on the in...

AI Technical Summary

Problems solved by technology

Regarding the compensation method for the time delay problem in transfer alignment, some literatures propose extrapolation filtering method, which can solve the time delay problem in transfer alignment very well, but the time delay must be known in advance to perform extrapolation, and the angular rate The time delay faced by the matching method cannot be measured in advance

There are also literatures that propose a state compensation method to compensate the time delay in transfer alignment, but this method must also know the size of the time delay in advance, and then perform state compensation

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