Research On Measurement And Compensation Methods For Bias And Scale Factor Errors Of Fiber Optic Gyroscope

Fiber optic gyroscope is one of the most important achievements in the field of optical fiber sensing.It has important applications in aerospace and maritime fields,with all the solid state,high dynamic range,high reliability and long life.At present,the technology of interferometric fiber optic gyroscope has been relatively mature,but the field of high-precision fiber optic gyroscope,there are still many technical points have not yet been a breakthrough in fiber inertial navigation system,fiber optic gyroscope is the core device.The error of fiber optic gyroscope is the main source of error in fiber inertial navigation system.The polarization effect of light,the back reflection or scattering in the fiber coil,the non-linear refractive index change,the electron drift error,the influence of the external temperature field,etc.,can produce nonreciprocal phase shift,which constitutes the fiber optic gyroscope Error source.However,even if the fiber optic gyroscope does a completely reciprocal system,there are still residual nonreciprocal phase shift,such as magneto-optical Faraday effect,polarization effect,temperature drift and other factors can be formed with the Sagneck effect can not distinguish between non-reciprocal Easy phase shift,resulting in output error,greatly reducing the accuracy of the gyro.In this paper,the output error of the optical fiber gyroscope brought by the external temperature field is analyzed and the design of the compensation scheme is put forward,and a new method to reduce the output noise of the fiber optic gyroscope is proposed.The main contents of this paper are as follows:Firstly,the basic principle of the operation of the fiber optic gyroscope is introduced,the basic working principle of the fiber optic gyroscope is discussed,the square wave offset technology and the stepped wave modulation method of the common closed-loop fiber optic gyroscope are described.Then the main sources of error of the fiber optic gyroscope are analyzed,and the evaluation method of the performance index of the fiber optic gyroscope is introduced,which lays the foundation for the follow-up study.Then,the temperature error of the scale factor of the fiber optic gyroscope is analyzed.According to the mechanism of the scale factor of the fiber optic gyro scale,the method of suppressing the scale factor error is put forward,and the scale factor test experiment under different temperature points is designed and finally The linear scheme is used to compensate the scale factor temperature error,and the system test experiment is carried out to verify the practicability of the compensation scheme.In addition,a linear model of zero bias with respect to temperature series is established for the zero drift drift of fiber optic gyroscope.Based on the traditional least squares compensation scheme,a closed least squares algorithm is proposed.Output data to verify that this new compensation scheme is superior to the traditional scheme.Finally,it is proposed to use the variable order LMS to find the optimal order for the adaptive filter to reduce the noise of the fiber optic gyroscope.This method can effectively suppress the output noise of the fiber optic gyroscope and provide a good basis.