Method for testing and compensating asymmetry error of scale factor of fiber-optic gyroscope

Abstract

The invention belongs to the technical field of fiber-optic gyroscope testing, and particularly relates to a method for testing and compensating asymmetric errors of scale factors of a fiber-optic gyroscope. Comprising the following steps: (1) quickly aligning inertial navigation equipment; (2) testing the static zero offset of the azimuth gyroscope to be tested; (3) calculating an equivalent zero offset error corresponding to the asymmetry error of the gyro scale factor; (4) calculating a compensation model according to the swing spectrum and the equivalent zero offset error; and (5) a gyro scale factor asymmetric error compensation model. A rotary table is adopted to simulate live swing, calculation and parameter fitting are carried out on dynamic error accumulation excited by scale factor asymmetry errors in the swing reciprocating motion of the gyroscope, compensation of the scale factor asymmetry errors of the fiber-optic gyroscope is achieved, universality is high, and testing can be easily and conveniently achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of inertial device testing, and in particular to a method for testing and compensating an asymmetric error of a fiber optic gyroscope scale factor. Background Art

[0002] With the advancement of navigation technology, fiber-optic gyro (FOG) inertial navigation systems (INNs) are becoming increasingly popular in the inertial field. During dynamic vehicle testing, particularly in lake and ocean environments, the vehicle on which the INNs are mounted is constantly swaying due to the influence of waves. Asymmetric errors in the scale factor, when stimulated by both positive and negative angular velocities, can produce significant equivalent gyro drift.

[0003] Usually, the calibration operation process of the scale parameters of the inertial navigation system does not consider the compensation problem of the asymmetric error of the gyroscope scale factor in the dynamic test environment. As a result, during the dynamic test, the system accuracy may be unstable due to the excitation of the dynamic environment.

[0004] Existing calibration methods only test the asymmetry of the scale factor at a specific rate, which is not suitable for actual application scenarios. Therefore, it is of great significance to design a gyroscope scale factor test method that is highly accurate, simple, convenient, and applicable to actual use scenarios. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a method for testing and compensating the asymmetric error of the scale factor of a fiber optic gyroscope.

[0006] The technical solution adopted by the present invention to solve its technical problem is: A method for testing and compensating the asymmetric error of a fiber optic gyroscope scale factor, comprising the following steps: (1) Rapid alignment of inertial navigation equipment; Install the inertial navigation device on the three-axis turntable. After the device is installed, power on the turntable, return each axis to zero, and keep it still. Wait for the temperature of the gyroscope and accelerometer to stabilize before starting the test. Determine the direction cosine matrix of the inertial navigation device using the alignment method of the solidified coordinate system , the inertial coordinate system is used as a reference benchmark, and two inertial coordinate systems are initially fixed, namely the initial navigation system n0 and the carrier system b0. Then the angular motion quaternion of the carrier relative to the inertial coordinate system is updated, and the transformation relationship between the gravity and the carrier linear motion between the two inertial coordinate systems is used to obtain the transformation matrix of the two solidified inertial coordinate systems, and thus the inverse is deduced ; (2) Testing of the static bias of the azimuth gyro to be tested; According to the alignment result of step (1), adjust the inner frame and middle frame of the three-axis turntable to -R and -P angles respectively, so that the horizontal attitude angle of the system is zero, and record the heading angle at this time as H 0； Navigation updates are performed according to the general attitude, speed, and position update algorithm of the inertial navigation system. The update frequency is 200Hz. After the inertial navigation update solution is completed every 5ms, the speed of the inertial navigation update is set to zero and the position is set to the local position. After 1h of inertial navigation algorithm update, the current heading angle is recorded as H 1； (3) Calculation of the equivalent bias error corresponding to the asymmetric error of the gyro scale factor; Static constant error under static conditions of the computing system On this basis, the additional error test caused by different swing spectra is calculated; (4) Calculate the compensation model based on the swing spectrum and equivalent bias error; Calculate the compensation model parameters corresponding to different sway spectra in step (3); (5) Gyro scale factor asymmetric error compensation model; According to the calculation result of step (4), the asymmetric error of the gyro scale factor is compensated.

[0007] Furthermore, the specific steps of step (1) are as follows: (1.1) Installation of inertial navigation equipment Install the inertial navigation device on a three-axis turntable, with the device's X, Y, and Z axes corresponding to the turntable's middle, inner, and outer frame axes, respectively. The Z-axis gyro is the fiber optic gyroscope to be tested. After the device is installed, power on the turntable, return each axis to zero, and keep it stationary. After powering on the device, wait for the temperature of the gyro and accelerometer to stabilize (temperature change of less than 1°C within 1 hour) before starting the test. (1.2) Alignment method for quick alignment First decompose the azimuth cosine matrix into: ; in, Represents the direction cosine matrix from the carrier coordinate system to the Earth's geographic coordinate system, Represents the direction cosine matrix from the geographic coordinate system at the solidification moment to the geographic coordinate system at the current moment, Represents the direction cosine matrix from the carrier coordinate system to the geographic coordinate system at the solidification moment, The transformation matrix representing the carrier coordinate system at the current moment to the carrier coordinate system at the solidification moment; It can be broken down into: ; in is the direction cosine matrix from the geocentric coordinate system to the geographic coordinate system, is the direction cosine matrix from the geocentric coordinate system at the solidification moment to the geocentric coordinate system at the current moment, is the direction cosine matrix from the geographic coordinate system at the time of solidification to the geocentric coordinate system at the time of solidification; The direction cosine matrices are expanded as follows: ; ; ; in, and To align the longitude and latitude at the initial moment; and For alignment The longitude and latitude of the moment, t is the alignment time; The calculation method uses the attitude quaternion update to obtain the differential equation: ; in, For The corresponding quaternion representation is, is the quaternion representation of the carrier attitude at time k-1, is the quaternion representation of the carrier's attitude change from time k-1 to the current time; The corresponding equivalent rotation vector matrix is ; ; in is the angular displacement increment directly measured by the gyroscope; According to the change rules of vector coordinate system, establish The relevant conversion equation is: ; The matrix is ​​expanded as follows: ; ; in, is the acceleration measured by the accelerometer, is the gravitational acceleration of the local geographic coordinate system; By reversing the above formula, we can get The calculation formula is as follows: ; Finally, follow The direction cosine matrix of the current carrier posture can be calculated; Depend on The matrix elements of are used to extract the attitude angle in real time. The formula is as follows: ; ; ; Among them, P is the pitch angle, R is the roll angle, and H is the heading angle.

[0008] Furthermore, the specific steps of step (2) are as follows: A solution cycle is defined as , the time interval is ; Record The carrier posture at the moment is , corresponding to The quaternion at time is , the quaternion attitude update formula is: ; in, and Respectively represent the rotation angles of the navigation coordinate system and the carrier coordinate system relative to the inertial space. The corresponding equivalent rotation vectors need to be calculated respectively. Indicates a record point at a certain moment. Indicates the previous record point at a certain moment; for Updates require the use of Integrate to get the equivalent rotation vector ; ; The matrix is ​​expanded as follows: ; and The corresponding equivalent rotation vector is , the calculation method is as follows: ; Since the speed and position will be set to zero speed and local position, their update process can be ignored; According to the navigation solution with an update frequency of 1 hour, the static zero position of the gyro to be tested can be obtained as: ; Where: is the static constant error, To quickly align and adjust the heading angle after the turntable is leveled, It is the heading angle of the carrier after 1 hour of navigation.

[0009] Further, the specific steps of step (3) are as follows: Repeat the processes of step (1) and step (2), change the static holding for 1 h after alignment and leveling in step 2 to keep the inner frame of the middle frame locked, change the static holding for 1 h after alignment and leveling in step 2 to keep the inner frame of the middle frame locked, and operate according to the parameters of different dynamic test swing spectra; For the outer frame, for each swing spectrum, perform a 1-h swing, record the change amount dH of the heading angle before and after each swing, and subtract the static constant error , and record the positions of dHi in the table respectively, where i represents the number of the swing spectrum.

[0010] Further, the specific steps of step (4) are as follows: Calculate, in step (3), for different swing spectra i, the integral of the positive swing angular velocity within the corresponding rate range of swing spectrum i ; ; ; Calculate the integral of the positive swing angular velocity corresponding to the angular rate lower than corresponding to (j < i) swing positive angular velocity, and the calculation method is as follows: ; ; Calculate the corresponding scale factor asymmetry error dki as ; The relevant parameters of the scale factor asymmetry error at different angular rates are obtained through the above formula.

[0011] Further, the specific steps of step (5) are as follows: According to the calculation results of step (4), compensate for the asymmetry error of the scale factor of the gyroscope, and the compensation method is as follows: ; [[ID=**47**]]where is the gyro angular rate calculated in real time.

[0012] The advantages and positive effects achieved by the present invention are as follows: 1. The design of the present invention uses a turntable to simulate the actual swing, calculates and fits the parameters of the dynamic error accumulation excited by the scale factor asymmetry error during the reciprocating swing of the gyroscope, realizes the compensation of the scale factor asymmetry error of the fiber optic gyroscope, and this technology has strong versatility and can be simply and conveniently implemented for testing.

[0013] Note: In the translation, the content in is not clearly shown in the original text, so it is retained as is in the translation. If there is a specific content in the original , it needs to be filled in accurately for a more complete translation. Also, the "**47**" in the translation of line ID=47 is added to show the position for reference.2. The method designed in the present invention uses dynamic swing data for calculation and compensation, avoiding the disadvantage of traditional test methods that can only calculate the asymmetric error of the scale factor at certain fixed rates, and realizing effective compensation at all rates.

[0014] 3. The method designed in the present invention can compensate for the angular velocity error caused by the asymmetric scale factor error due to the periodic change of angular velocity during operation of the fiber optic gyroscope, which can effectively improve the attitude measurement accuracy under dynamic swing conditions and enhance the dynamic environment adaptability of inertial navigation products. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the process of the fast alignment algorithm of the present invention; Figure 2 The figure is a three-dimensional schematic diagram of an installation structure of an inertial navigation device of the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described below with reference to the embodiments. The following embodiments are descriptive rather than restrictive, and the scope of protection of the present invention cannot be limited by the following embodiments.

[0017] The various experimental operations involved in the specific embodiments are all routine techniques in the field. For parts not specifically annotated in this document, ordinary technicians in this field can refer to various commonly used reference books, scientific literature or related instructions, manuals, etc. before the filing date of this invention to implement them.

[0018] A method for testing and compensating the asymmetric error of a fiber optic gyroscope scale factor, comprising the following steps: (1) Rapid alignment of inertial navigation equipment; (2) Testing of the static bias of the azimuth gyro to be tested; (3) Calculation of the equivalent bias error corresponding to the asymmetric error of the gyro scale factor; (4) Calculate the compensation model based on the swing spectrum and equivalent bias error; (5) Gyro scale factor asymmetric error compensation model.

[0019] like Figure 1 As shown, specifically, the steps are as follows: (1) Rapid alignment of inertial navigation equipment; 1.1 Installation of inertial navigation equipment like Figure 2As shown in the figure, the inertial navigation device is installed on the three-axis turntable. The X-axis, Y-axis, and Z-axis of the device correspond to the middle frame rotation axis 1, inner frame rotation axis 2, and outer frame rotation axis 3 of the three-axis turntable, respectively. The Z-axis gyroscope is the fiber optic gyroscope to be tested. After the device is installed, the turntable is powered on, each axis returns to zero, and remains stationary. After the device is powered on, wait for the temperature of the gyroscope and accelerometer to stabilize (temperature change is less than 1°C in 1 hour) before starting the test.

[0020] 1.2 Alignment method for quick alignment Fast alignment uses the alignment method of the solidified coordinate system. The purpose of alignment is to determine the direction cosine matrix of the inertial navigation device. The basic method of the scheme uses the inertial coordinate system as the reference benchmark, initially fixing two inertial coordinate systems, namely the initial navigation system n0 and the carrier system b0, and then updating the angular motion quaternion of the carrier relative to the inertial coordinate system, and using the transformation relationship between gravity and carrier linear motion between the two inertial coordinate systems to obtain the transformation matrix of the two solidified inertial coordinate systems, and then inferring .

[0021] First decompose the azimuth cosine matrix into: ; in, Represents the direction cosine matrix from the carrier coordinate system to the Earth's geographic coordinate system, Represents the direction cosine matrix from the geographic coordinate system at the solidification moment to the geographic coordinate system at the current moment, Represents the direction cosine matrix from the carrier coordinate system to the geographic coordinate system at the solidification moment, Represents the transformation matrix from the carrier coordinate system at the current moment to the carrier coordinate system at the solidification moment.

[0022] It can be broken down into: ; in is the direction cosine matrix from the geocentric coordinate system to the geographic coordinate system, is the direction cosine matrix from the geocentric coordinate system at the solidification moment to the geocentric coordinate system at the current moment, is the direction cosine matrix from the geographic coordinate system at the time of solidification to the geocentric coordinate system at the time of solidification.

[0023] The direction cosine matrices are expanded as follows: ; ; ; in, and To align the longitude and latitude at the initial moment; and For alignment The longitude and latitude of the moment, t is the alignment time.

[0024] The calculation method uses the attitude quaternion update to obtain the differential equation: ; in, For The corresponding quaternion representation is, is the quaternion representation of the carrier attitude at time k-1, It is the quaternion representation of the carrier's attitude change from time k-1 to the current time.

[0025] The corresponding equivalent rotation vector matrix is .

[0026] ; in is the angular displacement increment directly measured by the gyroscope.

[0027] According to the change rules of vector coordinate system, establish The relevant conversion equation is: ; The matrix is ​​expanded as follows: ; ; in, is the acceleration measured by the accelerometer, is the gravitational acceleration in the local geographic coordinate system.

[0028] Reverse the above formula to get The calculation formula is as follows: ; Finally, follow The direction cosine matrix of the current carrier posture can be calculated.

[0029] Depend on The matrix elements of are used to extract the attitude angle in real time. The formula is as follows: ; ; ; Among them, P is the pitch angle, R is the roll angle, and H is the heading angle.

[0030] (2) Testing of the static bias of the azimuth gyro to be tested; According to the alignment result of step (1), adjust the inner frame and middle frame of the three-axis turntable to -R and -P angles respectively, so that the horizontal attitude angle of the system is zero, and record the heading angle at this time as .

[0031] Navigation updates are performed according to the general attitude, speed, and position update algorithm of the inertial navigation system. The update frequency is 200Hz. After the inertial navigation update solution is completed every 5ms, the speed of the inertial navigation update is set to zero and the position is set to the local position. After 1h of inertial navigation algorithm update, the current heading angle is recorded as H 1. .

[0032] The specific calculation process is as follows: A solution cycle is defined as , the time interval is ; Record The carrier posture at the moment is , corresponding to The quaternion at time is , the quaternion attitude update formula is:

[0033] in, and Respectively represent the rotation angles of the navigation coordinate system and the carrier coordinate system relative to the inertial space. The corresponding equivalent rotation vectors need to be calculated respectively. Indicates a record point at a certain moment. Indicates the previous record point at a certain moment; for Updates require the use of Integrate to get the equivalent rotation vector .

[0034] ; The matrix is ​​expanded as follows: ; and The corresponding equivalent rotation vector is , the calculation method is as follows: ; Since the speed and position are set to zero speed and local position, their updates can be ignored.

[0035] According to the navigation solution with an update frequency of 1 hour, the static zero position of the gyro to be tested can be obtained as: ; Where: is the static constant error, To quickly align and adjust the heading angle after the turntable is leveled, It is the heading angle of the carrier after 1 hour of navigation.

[0036] (3) Calculation of the equivalent bias error corresponding to the asymmetric error of the gyro scale factor; Static constant error under static conditions of the computing system On this basis, calculate the additional error test caused by different swing spectra. Repeat the process of steps (1) and (2), and change the static hold of 1 hour after alignment and leveling in step 2 to keeping the middle frame and inner frame locked, and refer to the parameters of the dynamic test swing spectrum in Table 1 below for operation; Table 1 Dynamic test swing spectrum

[0037] For the outer frame, each time a swing spectrum in Table 1 is used to swing for 1 hour, and the change in heading angle dH before and after each swing is recorded, and the static constant error is subtracted. , recorded in the position of dHi in the table, where i represents the number of the swing spectrum.

[0038] Let Ai be the corresponding amplitude of the corresponding swing spectrum i, and Ti be the corresponding period of the corresponding swing spectrum i. = is the maximum angular velocity of the corresponding swing spectrum. According to the range of angular velocity that needs to be compensated by the device, swings of different amplitudes can be designed.

[0039] (4) Calculate the compensation model based on the swing spectrum and equivalent bias error; 4.1 In calculation step (3), the corresponding compensation model parameters of the swing spectrum 1 in Table 1 are calculated as follows: The integral of the positive angular velocity in the 1h reciprocating swing corresponding to the swing of swing spectrum 1 is: ; in, is the swing amplitude corresponding to the swing spectrum 1, is the swing period corresponding to the swing spectrum 1, and A11 is the swing angle corresponding to the accumulated positive angular velocity after 1 hour of swing according to the swing spectrum 1.

[0040] The corresponding scale factor asymmetry error is: ; That is The scale factor asymmetry error within the range is ; 4.2 Calculation step (3), the corresponding compensation model parameters of the swing spectrum 2 in Table 2 are: When calculating the swing spectrum 2, the swing spectrum 2 corresponds to the rate range The integral of the positive angular velocity of the swing , the calculation method is as follows: ; in, is the swing amplitude corresponding to the swing spectrum 2, is the swing period corresponding to the swing spectrum 2, and A22 is the swing angle corresponding to the accumulated positive angular velocity after 1 hour of swing according to the swing spectrum 2.

[0041] Calculate the corresponding velocity range in the swing spectrum 1 contained in the gyro data when swinging the swing spectrum 2 The integral of the positive angular velocity of the swing , the calculation method is as follows: ; According to the above equation , When swinging according to swing spectrum 2, the maximum angular velocity of swing spectrum 1 is reached. time point.

[0042] ; The corresponding scale factor asymmetry error is calculated as: ; 4.3 Calculation step (3), the corresponding compensation model parameters of the swing spectrum 2 in Table 2 are: When calculating the swing spectrum 3, the swing spectrum 3 corresponds to the rate range The integral of the positive angular velocity of the swing , the calculation method is as follows: ; in, is the swing amplitude corresponding to the swing spectrum 3, is the swing period corresponding to the swing spectrum 3, and A33 is the swing angle corresponding to the accumulated positive angular velocity after 1 hour of swing according to the swing spectrum 3.

[0043] Calculated below Different swing spectra below the rate correspond to the integral angle of the rate experience, and the angular velocity range is The integral of the positive angular velocity of the swing , the calculation method is as follows: ; in, When swinging according to swing spectrum 3, the maximum angular velocity of swing spectrum 2 is reached. time point.

[0044] Corresponding angular rate range Integrated positive angular velocity of sway within , the calculation method is as follows: ; Among them, is the time point corresponding to the maximum angular velocity of sway spectrum 1 when swaying according to sway spectrum 3 .

[0045] The calculated corresponding scale factor asymmetry error is: ; The calculation formula for the scale factor asymmetry error corresponding to other sway spectra is similar to that of sway 3. The formula is directly given as follows. The method for calculating the scale factor asymmetry error dKi of the gyro corresponding to sway i is as follows: When calculating sway spectrum i, the integrated positive angular velocity of sway within the rate range corresponding to sway spectrum i within

[0046] ; Calculate the integrated positive angular velocity of sway corresponding to when the angular rate is lower than (j < i) , the calculation method is as follows:​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Although the embodiments of the present invention are disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments.

Claims

1. A method for testing and compensating for asymmetric error in a fiber optic gyroscope scale factor, characterized by: Here are the steps: (1) Rapid alignment of inertial navigation equipment; Install the inertial navigation device on the three-axis turntable. After the device is installed, power on the turntable, return each axis to zero, and keep it still. Wait for the temperature of the gyroscope and accelerometer to stabilize before starting the test. Determine the direction cosine matrix of the inertial navigation device using the alignment method of the solidified coordinate system , the inertial coordinate system is used as a reference benchmark, and two inertial coordinate systems are initially fixed, namely the initial navigation system n0 and the carrier system b0. Then the angular motion quaternion of the carrier relative to the inertial coordinate system is updated, and the transformation relationship between the gravity and the carrier linear motion between the two inertial coordinate systems is used to obtain the transformation matrix of the two solidified inertial coordinate systems, and thus the inverse is deduced ; (2) Testing of the static bias of the azimuth gyro to be tested; According to the alignment result of step (1), adjust the inner frame and middle frame of the three-axis turntable to -R and -P angles respectively, so that the horizontal attitude angle of the system is zero, and record the heading angle at this time as H 0； Navigation updates are performed according to the general attitude, speed, and position update algorithm of the inertial navigation system. The update frequency is 200Hz. After the inertial navigation update solution is completed every 5ms, the speed of the inertial navigation update is set to zero and the position is set to the local position. After 1h of inertial navigation algorithm update, the current heading angle is recorded as H 1； (3) Calculation of the equivalent bias error corresponding to the asymmetric error of the gyro scale factor; Static constant error under static conditions of the computing system On this basis, the additional error test caused by different swing spectra is calculated; (4) Calculate the compensation model based on the swing spectrum and equivalent bias error; Calculate the compensation model parameters corresponding to different sway spectra in step (3); (5) Gyro scale factor asymmetric error compensation model; According to the calculation result of step (4), the asymmetric error of the gyro scale factor is compensated.

2. The method according to claim 1, wherein: Step (1) The specific steps are as follows: (1.1) Installation of inertial navigation equipment Install the inertial navigation device on a three-axis turntable, with the device's X, Y, and Z axes corresponding to the turntable's middle, inner, and outer frame axes, respectively. The Z-axis gyro is the fiber optic gyroscope to be tested. After the device is installed, power on the turntable, return each axis to zero, and keep it stationary. After powering on the device, wait for the temperature of the gyro and accelerometer to stabilize (temperature change of less than 1°C within 1 hour) before starting the test. (1.2) Alignment method for quick alignment First decompose the azimuth cosine matrix into: ； in, Represents the direction cosine matrix from the carrier coordinate system to the Earth's geographic coordinate system, Represents the direction cosine matrix from the geographic coordinate system at the solidification moment to the geographic coordinate system at the current moment, Represents the direction cosine matrix from the carrier coordinate system to the geographic coordinate system at the solidification moment, The transformation matrix representing the carrier coordinate system at the current moment to the carrier coordinate system at the solidification moment; It can be broken down into: ； in is the direction cosine matrix from the geocentric coordinate system to the geographic coordinate system, is the direction cosine matrix from the geocentric coordinate system at the solidification moment to the geocentric coordinate system at the current moment, is the direction cosine matrix from the geographic coordinate system at the time of solidification to the geocentric coordinate system at the time of solidification; The direction cosine matrices are expanded as follows: ； ； ； in, and To align the longitude and latitude at the initial moment; and For alignment The longitude and latitude of the moment, t is the alignment time; The calculation method uses the attitude quaternion update to obtain the differential equation: ； in, For The corresponding quaternion representation is, is the quaternion representation of the carrier attitude at time k-1, is the quaternion representation of the carrier's attitude change from time k-1 to the current time; The corresponding equivalent rotation vector matrix is ; ； in is the angular displacement increment directly measured by the gyroscope; According to the change rules of vector coordinate system, establish The relevant conversion equation is: ； The matrix is ​​expanded as follows: ； ； in, is the acceleration measured by the accelerometer, is the gravitational acceleration of the local geographic coordinate system; Reverse the above formula to get The calculation formula is as follows: ； Finally, follow The direction cosine matrix of the current carrier posture can be calculated; Depend on The matrix elements of are used to extract the attitude angle in real time. The formula is as follows: ； ； ； Among them, P is the pitch angle, R is the roll angle, and H is the heading angle.

3. The method according to claim 1, wherein: Step (2) The specific steps are as follows: A solution cycle is defined as , the time interval is ; Record The carrier posture at the moment is , corresponding to The quaternion at time is , the quaternion attitude update formula is: ； in, and Respectively represent the rotation angles of the navigation coordinate system and the carrier coordinate system relative to the inertial space. The corresponding equivalent rotation vectors need to be calculated respectively. Indicates a record point at a certain moment. Indicates the previous record point at a certain moment; for Updates require the use of Integrate to get the equivalent rotation vector ; ； The matrix is ​​expanded as follows: ； and The corresponding equivalent rotation vector is , the calculation method is as follows: ； Since the speed and position will be set to zero speed and local position, their update process can be ignored; According to the navigation solution with an update frequency of 1 hour, the static zero position of the gyro to be tested can be obtained as: ； Where: is the static constant error, To quickly align and adjust the heading angle after the turntable is leveled, It is the heading angle of the carrier after 1 hour of navigation.

4. The method according to claim 1, wherein: Step (3) The specific steps are as follows: Repeat the process of steps (1) and (2), and change the static holding for 1 hour after alignment and leveling in step 2 to keeping the middle frame and inner frame locked, and change the static holding for 1 hour after alignment and leveling in step 2 to keeping the middle frame and inner frame locked, and operate according to different parameters of dynamic test swing spectrum; For the outer frame, one swing spectrum is taken each time, and the swing is performed for 1 hour. The change in the heading angle before and after each swing is recorded, and the static constant error is subtracted. , recorded in the position of dHi in the table, where i represents the number of the swing spectrum.

5. The method according to claim 1, wherein: Step (4) The specific steps are as follows: In the calculation step (3), for different swing spectra i, the swing spectrum i corresponds to the rate range The integral of the positive angular velocity of the swing ; ； The calculated angular rate is lower than corresponding the integral of the positive angular velocity of rocking ((j < i)) , and the calculation method is as follows: ； Calculate the corresponding scale factor asymmetry error dki as ； The relevant parameters of the scale factor asymmetry error at different angular rates are obtained through the above formula.

6. The method according to any one of claims 1 to 5, characterized in that: Step (5) The specific steps are as follows: According to the calculation result of step (4), the asymmetric error of the gyro scale factor is compensated. The compensation method is as follows: ； in is the gyro angular rate calculated in real time.

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