A multi-redundant fiber-optic inertial measurement unit fault detection method and system

Abstract

This invention discloses a fault detection method for a multi-redundant fiber optic inertial navigation system (INS), comprising: measuring to obtain raw pulse data of the multi-redundant INS, wherein the multi-redundant INS includes three orthogonal axes and one to three tilt axes; calibration testing to obtain calibration parameters of the INS; based on the calibration parameters, obtaining output data of each tilt axis, and after tool error compensation, obtaining output data of each orthogonal axis in the orthogonal calibration system; subtracting the output data of each tilt axis from the output data of each orthogonal axis in the orthogonal calibration system, comparing the absolute value of the difference with the corresponding tilt axis fault threshold value, obtaining the corresponding fault discrimination code, and determining the fault status of the tilt axis or orthogonal axis based on the fault discrimination code. This invention provides a new fault detection approach for redundant meter header schemes, effectively reducing costs while improving the accuracy and efficiency of fault detection and location, and enhancing product reliability.

Description

Technical Field

[0001] This invention relates to the field of inertial measurement technology, and more specifically, to a method and system for fault detection of multi-redundant fiber optic inertial navigation systems. Background Technology

[0002] In the commercial aerospace sector, there is a strong demand for low-cost, high-reliability strapdown inertial navigation systems (INS). Traditional INS designs typically rely on individual inertial devices to measure angular velocity and acceleration. When a single inertial device fails, it affects overall navigation accuracy or even renders navigation information completely unusable, resulting in low product reliability.

[0003] To improve product reliability, redundancy technology is necessary. Compared to system redundancy schemes, header redundancy schemes can effectively reduce costs. As measurement devices for navigation and guidance of launch vehicles, the reliability of multi-redundant inertial navigation systems (INS) is a key factor in the success or failure of flight missions. Fault detection, as a crucial link in redundancy technology, has always been a research hotspot for many researchers, and fault detection in header redundancy schemes is a technical problem that urgently needs to be solved. Summary of the Invention

[0004] In response to at least one defect or improvement requirement in the prior art mentioned in the background section, this invention provides a multi-redundant fiber optic inertial navigation system (INS) fault detection method and system. This provides a new fault detection approach for the redundancy scheme of the meter header, which can effectively reduce costs while improving the accuracy and efficiency of fault detection and location, thereby enhancing product reliability.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for fault detection of multi-redundant fiber optic inertial navigation systems, comprising:

[0006] Measurements are taken to obtain raw pulse data from the multi-redundant fiber optic inertial navigation system; the multi-redundant fiber optic inertial navigation system includes three orthogonal axes and one to three tilt axes.

[0007] Calibration tests are conducted to obtain the calibration parameters of the multi-redundant fiber optic inertial navigation system.

[0008] Based on the calibration parameters, the output data of each tilt axis is obtained, and the original pulse data of the three orthogonal axes are compensated for tool error to obtain the output data of each orthogonal axis of the orthogonal calibration system.

[0009] The output data of each tilt axis is subtracted from the output data of each orthogonal axis of the orthogonal calibration system. The absolute value of the difference is compared with the corresponding tilt axis fault threshold value to obtain the corresponding fault discrimination code. The fault condition of the tilt axis or orthogonal axis is determined based on the fault discrimination code.

[0010] Furthermore, the raw pulse data includes the pulse counts of four to six fiber optic gyroscopes and the pulse counts of four to six add-in tables.

[0011] Furthermore, the calibration test includes:

[0012] Calibration tests were performed using the 20-position calibration method.

[0013] Complete the calibration parameter calculation for the three orthogonal axes;

[0014] Calculate the deflection angles between each tilt axis and the three orthogonal axes.

[0015] Furthermore, the twenty-position calibration method includes:

[0016] The three orthogonal axes correspond to twenty positions: up northeast, up north west, up southwest, up south east, up north east, down north east, down north west, up north west, down northwest, down south west, down southeast, down north east, up northeast, down northwest, down south west, up east south, up west, down west north, down east north, down south east, down west south. The arrangement strategy is static-flipped-static.

[0017] Furthermore, the calibration parameter calculation includes the calculation of one or more of the following: gyroscope zero position, gyroscope scale, gyroscope mounting angle, gauge zero position, gauge scale, and gauge mounting angle.

[0018] Furthermore, the tool error compensation model includes a gyroscope error compensation model and a dialing error compensation model;

[0019] The gyroscope error compensation model can be expressed as:

[0020]

[0021]

[0022] Where, δθ x1 ,δθ y1 ,δθ z1 δθ' represents the angular increments on the three orthogonal axes within the sampling period. x1 ,δθ' y1 ,δθ' z1 θ represents the pulse count increment of the three channels of the gyroscope within the sampling period. x0 ,θ y0 ,θ z0 E represents the pulse count increment caused by the gyroscope's zero position. 1x E 1y E 1z E is the gyroscope scale; yx E zx E xy E zy Exz E yz Install an offset angle on the gyroscope;

[0023] The table addition error compensation model can be expressed as:

[0024]

[0025]

[0026] Among them, δW x1 ,δW y1 ,δW z1 For apparent velocity increment; δW x '1,δW y '1,δW z '1' represents the increment of the number of pulses output by the three adders within the sampling period; W x0 W y0 W z0 K is the pulse count increment caused by adding the zero position to the table. 1x K 1y K 1z The scale is added to the table; K yx K zx K xy K zy K xz K yz Install the offset angle for the added table.

[0027] Furthermore, the relevant discriminant formula for subtracting the output data of each tilt axis from the output data of each orthogonal axis of the orthogonal calibration system and comparing the absolute value of the difference with the corresponding tilt axis fault threshold value can be expressed as:

[0028] First discriminant:

[0029] Second discriminant:

[0030] Third discriminant:

[0031] Fourth discriminant:

[0032] Fifth discriminant:

[0033] Sixth discriminant:

[0034] Seventh discriminant:

[0035] Eighth discriminant:

[0036] Ninth discriminant:

[0037] Tenth discriminant:

[0038] Eleventh discriminant:

[0039] Twelfth discriminant:

[0040] Thirteenth discriminant:

[0041] Fourteenth discriminant:

[0042] Fifteenth discriminant:

[0043] Sixteenth discriminant:

[0044] Seventeenth discriminant:

[0045] Eighteenth discriminant: One or more of the following;

[0046] Wherein, sin(r) xs ),sin(r ys ),sin(r zs ) represents the projection coefficients of the first tilt-axis gyroscope onto the three orthogonal axes.

[0047] These are the projection coefficients of the second tilt-axis gyroscope onto the three orthogonal axes.

[0048] The projection coefficients of the third tilt axis gyroscope onto the three orthogonal axes;

[0049] sin(t xs ),sin(t ys ),sin(t zs The projection coefficients from the first tilt axis to the three orthogonal axes are given.

[0050] Add projection factors to the second tilt axis onto the three orthogonal axes.

[0051] Add projection coefficients to the third tilt axis onto the three orthogonal axes;

[0052] ε xs ,ε ys ,ε zs , This is the fault threshold value for the first tilt axis; This is the fault threshold value for the second tilt axis; This is the fault threshold value for the third tilt axis;

[0053] δθ x ,δθ y ,δθ z , These are the angle increments on each tilt axis and orthogonal axis;

[0054] δW x ,δW y ,δW z ,δW s , This represents the apparent velocity increments on each tilt axis and orthogonal axis.

[0055] Furthermore, based on the discrimination results of the first to ninth discriminant equations, the corresponding fault discrimination code is obtained, and the gyroscope fault is determined based on the fault discrimination code. The specific discrimination process includes:

[0056] In the sequential judgment of the first to the ninth discriminant, if the calculation result is consistent, it is marked as "1" and if the calculation result is inconsistent, it is marked as "0", so as to obtain a nine-bit fault discrimination code;

[0057] If the fault identification code is "111111111", then the gyroscope is determined to be fault-free.

[0058] If the fault identification code is "011011011", then it is determined to be a fault of the first orthogonal axis gyroscope;

[0059] If the fault identification code is "101101101", then it is determined to be a fault in the second orthogonal axis gyroscope;

[0060] If the fault identification code is "110110110", then it is determined to be a fault in the third orthogonal axis gyroscope;

[0061] If the fault identification code is "000111111", then it is determined to be a fault in the first tilt axis gyroscope;

[0062] If the fault identification code is "111000111", then it is determined to be a fault in the second tilt axis gyroscope;

[0063] If the fault identification code is "111111000", then it is determined to be a fault in the third tilt axis gyroscope.

[0064] Furthermore, based on the discrimination results of the tenth to eighteenth discriminant equations, the corresponding fault discrimination code is obtained, and the table addition fault is determined based on the fault discrimination code. The specific discrimination process includes:

[0065] In the sequential judgment of the tenth to eighteenth discriminants, if the calculation result is consistent, it is marked as "1" and if the calculation result is inconsistent, it is marked as "0", thereby obtaining a nine-bit fault discrimination code;

[0066] If the fault identification code is "111111111", then it is determined that there is no fault in adding the table.

[0067] If the fault identification code is "011011011", then it is determined to be a fault in the first orthogonal axis addition table;

[0068] If the fault identification code is "101101101", then it is determined to be a fault in the second orthogonal axis addition table;

[0069] If the fault identification code is "110110110", then it is determined to be a fault in the third orthogonal axis addition table;

[0070] If the fault identification code is "000111111", then it is determined to be a fault in the first tilt axis dial indicator.

[0071] If the fault identification code is "111000111", then it is determined to be a fault in the second tilting axis dial indicator;

[0072] If the fault identification code is "111111000", then it is determined to be a fault in the third tilt axis addition.

[0073] To achieve the above objectives, in a second aspect, the present invention provides a multi-redundant fiber optic inertial navigation system fault detection system, which is capable of implementing any of the fault detection methods described above.

[0074] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0075] This invention obtains a fault identification code by subtracting the output data of each tilt axis from the output data of each orthogonal axis in the orthogonal calibration system, and comparing the absolute value of the difference with the corresponding tilt axis fault threshold. Based on this fault identification code, the fault status of the tilt axis or orthogonal axis is determined. This invention provides a new fault detection approach for redundancy meter headers, effectively reducing costs while improving the accuracy and efficiency of fault detection and location, thus enhancing product reliability. Attached Figure Description

[0076] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0077] Figure 1 This is a flowchart illustrating a multi-redundant fiber optic inertial navigation system fault detection method provided in an embodiment of the present invention.

[0078] Figure 2 This is a schematic diagram of the installation direction of the inertial instrument provided in an embodiment of the present invention. Detailed Implementation

[0079] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0080] The terms "first," "second," or "third," etc., used in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a particular order. Furthermore, the terms "comprising" or "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0081] like Figure 1 As shown, in one embodiment, a fault detection method for a multi-redundant fiber optic inertial navigation system (FIS) is provided. The multi-redundant FIS includes four to six fiber optic gyroscopes. X W Y W Z Ws, Ws1, Ws2 and four to six additional tables A X A Y A Z , As, As1, As2, where W X W Y W Z The three gyroscopes are orthogonal gyroscopes, Ws, Ws1, and Ws2 are spatially tilted gyroscopes, and A... X A Y A Z The three addition tables are orthogonal addition tables, and As, As1, and As2 are spatially tilted addition tables. The method mainly includes the following steps.

[0082] Step 1: Measure to obtain raw pulse data from the multi-redundant fiber optic inertial navigation system, which includes three orthogonal axes and one to three tilt axes (see reference). Figure 2The first orthogonal axis X-axis, the second orthogonal axis Y-axis, and the third orthogonal axis Z-axis are three orthogonal axes, while the first tilt axis S-axis, the second tilt axis S1 axis, and the third tilt axis S2 axis are three tilt axes. A multi-redundant fiber optic inertial navigation system may include one, two, or three of these tilt axes.

[0083] The raw pulse data includes four to six fiber optic gyroscopes W X W Y W Z The number of pulses for Ws, Ws1, and Ws2, and four to six additions to Table A. X A Y A Z The pulse counts of As, As1, and As2, and the installation orientation of each meter are as follows: Figure 2 As shown.

[0084] Step 2: Through calibration tests and calibration parameter calculations, the calibration parameters of the multi-redundant fiber optic inertial navigation system are obtained. These calibration parameters include the installation angle relationship between the tilt axes S, S1, and S2 and the orthogonal calibration coordinate system (hereinafter referred to as the orthogonal calibration system or calibration system) XYZ.

[0085] The calibration test includes the following three steps:

[0086] Step 21: Complete the 20-position calibration test. The 20-position calibration method includes 20 positions corresponding to the XYZ directions: Up Northeast - Up North West - Up Southwest - Up South East - North Up East - North East Down - North Down West - North West Up - Down Northwest - Down South West - Down Southeast - Down North East - Northeast Up - Northwest Down - South Up West - East Up South - West Up North - East Down North - South Down East - West Down South. A static-flip-static reordering strategy is used.

[0087] Step 22: Complete the X, Y, and Z axis calibration parameter calculations. The calibration parameter calculations include the gyroscope zero position D. 0x D 0y D 0z gyroscope scale E 1x E 1y E 1z Gyroscope mounting angle E yx E zx E xy E zy E xz E yz Add table zero position K 0x K 0y K 0z Add scale K 1x K 1y K 1z Add table installation offset angle K yx K zx K xyK zy K xz K yz One or more of the following calculations.

[0088] Step 23: Complete the deflection angle r between the tilt axes S, S1, S2 and the X, Y, Z axes. xs r ys r zs , The calculation.

[0089] Step 3: Based on the calibration parameters, obtain the output data of each tilt axis, and after compensating for tool error, obtain the output data of each orthogonal axis of the orthogonal calibration system.

[0090] The tool error compensation models include a gyroscope error compensation model and a dial gauge error compensation model.

[0091] If D is ignored 1x D 2x D 3x D 1y D 2y D 3y D 1z D 2z D 3z The influence of this, the error compensation formula for the gyroscope tool is:

[0092]

[0093]

[0094] In the above formula, δθ x1 ,δθ y1 ,δθ z1 δθ' represents the angular increments on the three orthogonal axes within the sampling period, in rad. x1 ,δθ' y1 ,δθ' z1 The increment of the number of pulses in the three channels of the gyroscope within the sampling period, in units of ∧; θ x0 ,θ y0 ,θ z0 The increment of pulse count caused by the gyroscope being at zero position, in π.

[0095] If we ignore the quadratic term K in the table 2x ,K 2y ,K 2z The error compensation formula for the table tool is as follows:

[0096]

[0097]

[0098] In the above formula, δW x1 ,δW y1 ,δW z1 Apparent velocity increment, unit: m / s; δW x '1,δW y '1,δW z '1' represents the increment of the number of output pulses by the three adders within the sampling period, in units of ∧; W. x0 W y0 W z0 The pulse count increment caused by adding three zero positions to the meter, in m / s.

[0099] Step 4: Subtract the output data of each tilt axis from the output data of each orthogonal axis of the orthogonal calibration system, and compare the absolute value of the difference with the corresponding tilt axis fault threshold value to obtain the corresponding fault discrimination code. Based on the fault discrimination code, determine the fault status of the tilt axis or orthogonal axis.

[0100] Fault detection can be performed using the following formula:

[0101] Formula 1:

[0102] Formula 2:

[0103] Formula 3:

[0104] Formula 4:

[0105] Formula 5:

[0106] Formula 6:

[0107] Formula 7:

[0108] Formula 8:

[0109] Formula 9:

[0110] Formula 10:

[0111] Formula 11:

[0112] Formula 12:

[0113] Formula 13:

[0114] Formula 14:

[0115] Formula 15:

[0116] Formula 16:

[0117] Formula 17:

[0118] Formula 18:

[0119] Wherein, sin(r) xs ),sin(r ys ),sin(r zs ) represents the projection coefficients from the S-axis gyroscope to the X, Y, and Z axes. These are the projection coefficients from the S1-axis gyroscope to the X, Y, and Z axes. These are the projection coefficients from the S2-axis gyroscope to the X, Y, and Z axes.

[0120] sin(t xs ),sin(t ys ),sin(t zs The projection coefficient from the S-axis to the X, Y, and Z axes is denoted as . Add projection factors from the S1 axis to the X, Y, and Z axes. Add projection factors to the S2 axis onto the X, Y, and Z axes.

[0121] ε xs ,ε ys ,ε zs , This is the fault threshold value for the S-axis; This is the fault threshold value for axis S1; δθ is the fault threshold value for axis S2. x ,δθ y ,δθ z ,δθ s , δW represents the angle increment on each axis. x ,δW y ,δW z ,δW s , This represents the apparent velocity increment on each axis.

[0122] Gyroscope faults can be identified using the discrimination formulas 1-9 and the gyroscope angle increment consistency fault identification and location table. The gyroscope angle increment consistency fault identification and location table is shown in Table 1 below.

[0123] Serial Number Formula 1 Formula 2 Formula 3 Formula 4 Formula 5 Formula 6 Formula 7 Formula 8 Formula 9 Judgment results 1 √ √ √ √ √ √ √ √ √ The gyroscope is working properly. 2 × √ √ × √ √ × √ √ X-gyroscope malfunction 3 √ × √ √ × √ √ × √ Y-gyroscope malfunction 4 √ √ × √ √ × √ √ × Z-gyroscope malfunction 5 × × × √ √ √ √ √ √ S-gyroscope malfunction 6 √ √ √ × × × √ √ √ S1 gyroscope malfunction 7 √ √ √ √ √ √ × × × S2 gyroscope malfunction

[0124] Table 1. Fault Location and Judgment Table for Gyro Angle Increment Consistency

[0125] The fault of adding a speedometer can be identified using the discrimination formula 10-18 and the fault identification and location table for the consistency of the speedometer increment. The fault identification and location table for the consistency of the speedometer increment is shown in Table 2 below.

[0126]

[0127]

[0128] Table 2. Fault Location Table for Consistency of Speed ​​Increment.

[0129] This method first uses a 20-position calibration method to obtain the installation angle relationship between the tilt axis and the orthogonal axis. Then, it compares the angle increments or apparent velocity increments of the tilt table and the orthogonal table using a set fault threshold value. Finally, it completes fault detection and location for each table using a consistent fault discrimination and location table. This invention provides a new fault detection approach for table head redundancy schemes, effectively reducing costs while improving the accuracy and efficiency of fault detection and location, thus enhancing product reliability.

[0130] In another embodiment of the present invention, a multi-redundant fiber optic inertial navigation system fault detection system is also provided, which can implement the fault detection method described above during operation or during its own operation.

[0131] The foregoing description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Other embodiments of this disclosure will be readily apparent to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This invention is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described herein. The specification and embodiments are to be considered exemplary only, and the scope and spirit of this disclosure are defined by the claims.

[0132] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0133] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-redundant fiber-optic inertial measurement unit fault detection method, comprising: include: Measurements are taken to obtain the raw pulse data of the multi-redundant fiber optic inertial navigation system; The multi-redundant fiber optic inertial navigation system includes three orthogonal axes and one to three tilt axes; Calibration tests are conducted to obtain the calibration parameters of the multi-redundant fiber optic inertial navigation system. Based on the calibration parameters, the output data of each tilt axis is obtained, and the original pulse data of the three orthogonal axes are compensated for tool error to obtain the output data of each orthogonal axis of the orthogonal calibration system. The output data of each tilt axis is subtracted from the output data of each orthogonal axis of the orthogonal calibration system, and the absolute value of the difference is compared with the corresponding tilt axis fault threshold value to obtain the corresponding fault discrimination code. The fault condition of the tilt axis or orthogonal axis is determined based on the fault discrimination code. The calibration test includes: Calibration tests were performed using the 20-position calibration method. Complete the calibration parameter calculation for the three orthogonal axes; Calculate the deflection angles between each tilt axis and the three orthogonal axes; Determining the fault status of the tilt axis or orthogonal axis based on the fault identification code includes: comparing the fault identification code with a preset angular increment consistency fault identification and location table or apparent velocity increment consistency fault identification and location table to identify the specific fault.

2. The fault detection method of claim 1, wherein, The raw pulse data includes the pulse counts of four to six fiber optic gyroscopes and the pulse counts of four to six add-in tables.

3. The fault detection method of claim 2, wherein, The twenty-position calibration method includes: The three orthogonal axes correspond to twenty positions: up northeast, up north west, up southwest, up south east, up north east, down north east, down north west, up north west, down northwest, down south west, down southeast, down north east, up northeast, down northwest, down south west, up east south, up west, down west north, down east north, down south east, down west south. The arrangement strategy is static-flipped-static.

4. The fault detection method of claim 2, wherein, The calibration parameter calculation includes one or more of the following: gyroscope zero position, gyroscope scale, gyroscope mounting angle, gauge zero position, gauge scale, and gauge mounting angle.

5. The fault detection method of claim 4, wherein, The tool error compensation models include a gyroscope error compensation model and a dial gauge error compensation model; The gyroscope error compensation model can be expressed as: in, The angle increments on the three orthogonal axes within the sampling period; This represents the pulse count increment of the three channels of the gyroscope within the sampling period; The increment of the number of pulses caused by the zero position of the gyroscope; The gyroscope scale; Install an offset angle on the gyroscope; The table addition error compensation model can be expressed as: in, For apparent velocity increments; This represents the increment of the number of pulses output by the three adders within the sampling period; The increment of the pulse count caused by adding the zero position to the table; Add a scale to the table; Install the offset angle for the added table.

6. The fault detection method as described in claim 5, characterized in that, The relevant discriminant formula for subtracting the output data of each tilt axis from the output data of each orthogonal axis of the orthogonal calibration system and comparing the absolute value of the difference with the corresponding tilt axis fault threshold value can be expressed as: First discriminant: Second discriminant: Third discriminant: Fourth discriminant: Fifth discriminant: Sixth discriminant: Seventh discriminant: Eighth discriminant: Ninth discriminant: Tenth discriminant: Eleventh discriminant: Twelfth discriminant: Thirteenth discriminant: Fourteenth discriminant: Fifteenth discriminant: Sixteenth discriminant: Seventeenth discriminant: Eighteenth discriminant: One or more of the following; in, These are the projection coefficients of the first tilt-axis gyroscope onto the three orthogonal axes. These are the projection coefficients of the second tilt-axis gyroscope onto the three orthogonal axes. The projection coefficients of the third tilt axis gyroscope onto the three orthogonal axes; Add projection coefficients from the first tilt axis to the three orthogonal axes. Add projection factors to the second tilt axis onto the three orthogonal axes. Add projection coefficients to the third tilt axis onto the three orthogonal axes; This is the fault threshold value for the first tilt axis; This is the fault threshold value for the second tilt axis; This is the fault threshold value for the third tilt axis; These are the angle increments on each tilt axis and orthogonal axis; This represents the apparent velocity increments on each tilt axis and orthogonal axis.

7. The fault detection method as described in claim 6, characterized in that, Based on the discrimination results of the first to ninth discriminant equations, the corresponding fault discrimination code is obtained, and the gyroscope fault is determined based on the fault discrimination code. The specific discrimination process includes: In the sequential judgment of the first to the ninth discriminant, if the calculation result is consistent, it is marked as "1" and if the calculation result is inconsistent, it is marked as "0", so as to obtain a nine-bit fault discrimination code; If the fault identification code is "111111111", then the gyroscope is determined to be fault-free. If the fault identification code is "011011011", then it is determined to be a fault of the first orthogonal axis gyroscope; If the fault identification code is "101101101", then it is determined to be a fault in the second orthogonal axis gyroscope; If the fault identification code is "110110110", then it is determined to be a fault in the third orthogonal axis gyroscope; If the fault identification code is "000111111", then it is determined to be a fault in the first tilt axis gyroscope; If the fault identification code is "111000111", then it is determined to be a fault in the second tilt axis gyroscope; If the fault identification code is "111111000", then it is determined to be a fault in the third tilt axis gyroscope.

8. The fault detection method as described in claim 6, characterized in that, Based on the discrimination results of the tenth to eighteenth discriminants, the corresponding fault discrimination codes are obtained, and the table addition fault is determined based on the fault discrimination codes. The specific discrimination process includes: In the sequential judgment of the tenth to eighteenth discriminants, if the calculation result is consistent, it is marked as "1"; if the calculation result is inconsistent, it is marked as "0", thereby obtaining a nine-bit fault discrimination code. If the fault identification code is "111111111", then it is determined that there is no fault in adding the table. If the fault identification code is "011011011", then it is determined to be a fault in the first orthogonal axis addition table; If the fault identification code is "101101101", then it is determined to be a fault in the second orthogonal axis addition table; If the fault identification code is "110110110", then it is determined to be a fault in the third orthogonal axis addition table; If the fault identification code is "000111111", then it is determined to be a fault in the first tilt axis dial indicator. If the fault identification code is "111000111", then it is determined to be a fault in the second tilt axis dial indicator; If the fault identification code is "111111000", then it is determined to be a fault in the third tilt axis addition.

9. A multi-redundant fiber optic inertial navigation system fault detection system, characterized in that, The fault detection system can implement the fault detection method according to any one of claims 1-8.

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