An accelerometer information-based two-set inertial navigation system installation error angle calibration method, program, device and storage medium

Abstract

The application provides a two-set inertial navigation system installation error angle calibration method based on accelerometer information, a program, equipment and a storage medium. A structure installed with two sets of inertial navigation systems is subjected to multi-angle transformation, a data matrix of three-axis accelerometer output of the two sets of inertial navigation systems within a period of time is obtained at each angle, and specific forces of the two sets of inertial navigation systems are calculated; based on the specific force data set of the two sets of inertial navigation systems, a to-be-optimized information matrix about installation attitude error angles is constructed by using a physical relationship equation; the to-be-optimized information matrix is decomposed, an optimal coordinate transformation matrix is calculated according to the decomposed matrix, and a pitch installation error, a roll installation error and a heading installation error between the two sets of inertial navigation systems are calculated according to elements in the optimal coordinate transformation matrix. The application can make up for the shortcomings of self-alignment and transfer alignment methods, can realize high-precision and rapid calibration of installation error angles between the two sets of inertial navigation systems, and has practical engineering application significance.

Description

Technical Field

[0001] This invention belongs to the field of inertial navigation system technology, specifically relating to a method, program, device, and storage medium for calibrating the installation error angle of two inertial navigation systems based on accelerometer information. Background Technology

[0002] Inertial navigation systems (INS) provide real-time and reliable attitude information for vehicles, making high-precision attitude estimation a crucial research area. Evaluating the accuracy of INS attitude estimation requires using higher-precision attitude information as a reference. Considering the real-time nature, flexibility, and wide-area capability of vehicle attitude estimation, this higher-precision attitude reference information is typically provided by another high-precision INS. Determining the installation attitude error between the low-precision INS to be evaluated and the reference high-precision INS is a critical prerequisite for achieving high-precision attitude evaluation.

[0003] Existing methods for determining the installation error angle between two inertial navigation systems (INS) can be mainly divided into two categories: self-alignment and transfer alignment. The self-alignment method allows the two INS systems to be initially aligned to obtain attitude results, and the difference is used to obtain the installation error angle between the INS systems. However, this type of method requires the use of gyroscope information from low-precision INS systems, and the magnitude of the alignment result error is often comparable to or even higher than the magnitude of the attitude evaluation accuracy, which cannot meet practical needs.

[0004] The transfer alignment method, which models the installation error angle and then uses information from two sets of inertial navigation systems (INS) to estimate the installation error angle in real time, has been used to solve the problem of online estimation of time-varying installation error angles of two INS systems on large vehicles. However, this type of method suffers from several drawbacks. First, the estimation accuracy is affected by the accuracy of the installation error angle model and the accuracy of the low-precision INS gyroscopes, making it unsuitable for practical applications. Second, during attitude assessment, the two INS systems are installed in close proximity, resulting in weak time-varying characteristics of the installation error angles. Furthermore, the online estimation method imposes additional computational burden on the INS systems, making it unsuitable for installation error angle calibration.

[0005] Therefore, it is necessary to invent a method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information that is fast, accurate, and reliable. Summary of the Invention

[0006] The purpose of this invention is to provide a method, program, device, and storage medium for calibrating the installation error angle of two inertial navigation systems based on accelerometer information.

[0007] A method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information includes:

[0008] The structure equipped with two inertial navigation systems is subjected to multi-angle transformations. At each angle, the data matrix output by the triaxial accelerometers of the two inertial navigation systems over a period of time is acquired, and the relative force between the two inertial navigation systems is calculated. The relative force dataset of the two inertial navigation systems is obtained through multi-angle transformations.

[0009] Based on the comparative force datasets of the two inertial navigation systems, an information matrix to be optimized about the installation attitude error angle is constructed using physical relation equations; if the information matrix to be optimized is a singular matrix, the above steps are repeated until the obtained information matrix to be optimized is a non-singular matrix.

[0010] The information matrix to be optimized is decomposed, and the optimal coordinate transformation matrix is ​​calculated based on the decomposed matrix. The pitch installation error, roll installation error and heading installation error between the two inertial navigation systems are calculated based on the elements in the optimal coordinate transformation matrix, and the installation error angle calibration of the two inertial navigation systems is completed.

[0011] Furthermore, at the i-th angle, the data matrix output by the triaxial accelerometer of the first inertial navigation system within time T0 is obtained. The data matrix output from the three-axis accelerometer of the second inertial navigation system F1 and F2 represent the data output frequencies of the first and second inertial navigation systems, respectively.

[0012] Furthermore, according to Calculate the specific force f of the first inertial navigation system i 1 :

[0013]

[0014] according to Calculate the specific force f of the first inertial navigation system i 2 :

[0015]

[0016] By performing N angle transformations, a comparison dataset of the two inertial navigation systems is obtained. and

[0017] Furthermore, based on the force dataset F of the two inertial navigation systems 1 With F 2 The physical relationship equation is used to construct the information matrix A to be optimized regarding the installation attitude error angle;

[0018] A = (F 1 w)(F 2 w) T

[0019] Where w is the accelerometer accuracy weight matrix, w = diag(w1,...,w N ), w i Let be the accuracy weight of the accelerometer at the i-th angle.

[0020] Furthermore, the information matrix A to be optimized is decomposed;

[0021] A = UDV T

[0022] In matrix U, each column is AA. T The eigenvectors; each column of matrix V is A T The eigenvectors of A; matrix D is a diagonal matrix, and each element on the main diagonal is a singular value of the information matrix A to be optimized.

[0023] Furthermore, the optimal coordinate transformation matrix is ​​calculated.

[0024] matrix Given a 3×3 matrix, according to the matrix... elements in u,v=1,2,3, calculate the pitch installation error θ, roll installation error β and heading installation error γ between the two inertial navigation systems;

[0025] like but

[0026] otherwise,

[0027] Furthermore, before starting the calibration, the two inertial navigation systems are powered on and preheated for a period of time.

[0028] A computer device / equipment / system includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-described method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information.

[0029] A computer-readable storage medium storing a computer program / instructions that, when executed by a processor, implements the steps of the above-described method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information.

[0030] A computer program product includes a computer program / instruction that, when executed by a processor, implements the steps of the above-described method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information.

[0031] The beneficial effects of this invention are as follows:

[0032] This invention enables high-precision and rapid calibration of the installation error angle between two inertial navigation systems, avoiding the accuracy degradation caused by low-precision gyroscopes in traditional methods. At the same time, considering the invariance of the installation error angle between the two inertial navigation systems in practical applications, this invention adopts an offline post-processing calculation method, reducing the computational burden on the inertial navigation system and having practical engineering application significance. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall process of the present invention.

[0034] Figure 2 This is a schematic diagram of the coordinate systems and placement of two inertial navigation systems provided in an embodiment of the present invention.

[0035] Figure 3 The figures show the calibration results of two sets of inertial navigation system installation error angles provided in the embodiments of the present invention.

[0036] Figure 4 The diagram shows the main performance indicators of two sets of inertial navigation devices provided in the embodiments of the present invention.

[0037] Figure 5 This is an attitude estimation error diagram of the inertial navigation system to be evaluated in a vehicle-mounted test provided in an embodiment of the present invention. Detailed Implementation

[0038] The present invention will now be further described with reference to the accompanying drawings.

[0039] This invention provides a method for calibrating the installation error angle of two inertial navigation systems (INS) based on accelerometer information. First, both INS systems are powered on and preheated to ensure normal output data. Simultaneously, accelerometer output data from both INS systems are collected, and the data is preprocessed to reduce noise. The horizontal attitude angles of the two INS systems are varied, and multiple sets of accelerometer data are collected to form an accelerometer dataset. Based on physical relationships, an optimization index function for the installation error angle is constructed using the accelerometer dataset, and the installation error angle is optimized and solved using a method based on SVD decomposition. This invention can overcome the shortcomings of self-alignment and transfer alignment methods, improve calibration accuracy, reduce the computational burden on the INS, and has practical engineering application significance.

[0040] Step 1: Perform multi-angle transformations on the structure equipped with two inertial navigation systems, acquire the data matrix output by the three-axis accelerometers of the two inertial navigation systems over a period of time at each angle, and calculate the relative force between the two inertial navigation systems; obtain the relative force dataset of the two inertial navigation systems through multi-angle transformations;

[0041] Obtain the data matrix output by the three-axis accelerometer of the first inertial navigation system within time T0 at the i-th angle. The data matrix output from the three-axis accelerometer of the second inertial navigation system F1 and F2 represent the data output frequencies of the first and second inertial navigation systems, respectively.

[0042] according to Calculate the specific force f of the first inertial navigation system i 1 :

[0043]

[0044] according to Calculate the specific force f of the first inertial navigation system i 2 :

[0045]

[0046] By performing N angle transformations, a comparison dataset of the two inertial navigation systems is obtained. and

[0047] Step 2: Comparison data set F based on two inertial navigation systems 1 With F 2 The physical relationship equation is used to construct the information matrix A to be optimized regarding the installation attitude error angle;

[0048] A = (F 1 w)(F 2 w) T

[0049] Where w is the accelerometer accuracy weight matrix, w = diag(w1,...,w N ), w i Let be the accuracy weight of the accelerometer at the i-th angle.

[0050] If the information matrix A to be optimized is a singular matrix, then repeat steps 1 and 2 until the obtained information matrix A to be optimized is a non-singular matrix.

[0051] Step 3: Decompose the information matrix A to be optimized;

[0052] A = UDV T

[0053] In matrix U, each column is AA. T The eigenvectors; each column of matrix V is A T The eigenvectors of A; matrix D is a diagonal matrix, where each element on the main diagonal is a singular value of the information matrix A to be optimized.

[0054] Calculate the optimal coordinate transformation matrix

[0055]

[0056] Among them, matrix It is a 3×3 matrix;

[0057] According to the matrix elements in u,v=1,2,3, calculate the pitch installation error θ, roll installation error β and heading installation error γ between the two inertial navigation systems;

[0058] like but

[0059] otherwise,

[0060] Example 1:

[0061] Step 1: Set up the experimental environment. This embodiment requires two inertial navigation systems (INS) containing accelerometers: the INS to be evaluated and a high-precision reference INS. Ensure that both INS have completed all calibration and testing, and that the origin of the INS coordinate system is the centroid of the INS, with the x, y, and z axes representing the right, front, and top of the INS, respectively. Connect the two INS using a rigid clamp, ensuring that the INS are sufficiently close and that there is no significant deformation during the experiment. Complete all power supply and data acquisition preparations. In this embodiment, the number of experiments n is set to 7, and the INS warm-up time t... preheat = 1 hour, data collection time t data =5 minutes, the output frequency of both inertial navigation systems is the same, 100Hz, F low =F high =100, accelerometer accuracy weight matrix w = diag([1 1...1]).

[0062] Step 2: Power on both inertial navigation systems and preheat for 1 hour to ensure that the inertial devices are working properly.

[0063] Step 3: Position the inertial navigation system in any manner. In this embodiment, the initial placement is as follows: Figure 2 As shown in the left figure; the coordinate systems of the two inertial navigation systems are clearly visible in the figure. low and I high There is an installation error angle. In this embodiment, to fully illustrate the usage details, the installation error angle is set to be relatively large.

[0064] Step 4: Save the accelerometer information output by the two inertial navigation systems. Record accelerometer data from both systems for 5 minutes at the initial position, with each accelerometer outputting 30,000 data points, resulting in two datasets. and

[0065]

[0066] in, and These are 30,000 data points output by the x, y, and z axis accelerometers of the inertial navigation system to be evaluated at the first position. and These are 30,000 data points output by the x, y, and z axis accelerometers of the high-precision reference inertial navigation system at the first position.

[0067] Step 5: Calculate the average of the 5-minute accelerometer data from the two inertial navigation systems using the following formula to eliminate white noise error and obtain f1. low and F1 low .

[0068]

[0069] in, and They are respectively and The i-th row of data, and They are respectively and The data in the i-th row.

[0070] Step 6: Determine if the required number of trials is met. If it is, proceed to step 11; otherwise, proceed to step 7.

[0071] Step 7: Adjust the horizontal attitude of both inertial navigation systems, rotating them by any angle α, where α > 30 degrees, such as... Figure 2 As shown in the middle image.

[0072] Step 8: After both inertial navigation systems have completed rotation and stabilized, record the accelerometer data from both systems for another 5 minutes to obtain the results. and

[0073]

[0074] in, and These are 30,000 data points output by the x, y, and z axis accelerometers of the inertial navigation system to be evaluated at the second position. and These are 30,000 data points output by the x, y, and z axis accelerometers of the high-precision reference inertial navigation system at the second position.

[0075] Step 9: Average the 5-minute accelerometer data from the two inertial navigation systems at this location using the following formula to eliminate white noise error and obtain... and

[0076]

[0077] Step 10: Repeat steps 6 to 9 until the number of trials is met. In this embodiment, the number of trials is set to 7.

[0078] Step 11: Reassemble the accelerometer data from the two inertial navigation systems at the nine saved locations to obtain... and

[0079]

[0080]

[0081] Step 12: Calculate the optimal coordinate transformation matrix. In this embodiment, the experimental environment remains unchanged, and the accelerometer data accuracy of the two inertial navigation systems at each position is the same. Therefore, the weights are taken as an equal-weight matrix, and the installation error angle information matrix to be optimized is constructed as A = (f 1 (f) 2 ) T .

[0082] Step 14: Optimize and decompose the information matrix A of the installation error angle to be optimized, and obtain A = UDV T .

[0083] Step 15: Solve for the optimal coordinate transformation matrix

[0084] Step 16: Calculate the pitch angle error θ, roll angle error β, and heading angle error γ of the coordinate system of the inertial navigation system to be evaluated relative to the high-precision inertial navigation system coordinate system.

[0085] Depend on Figure 3 As can be seen from the data, the standard deviations of the installation error angles of the pitch angle, roll angle, and yaw angle calibrated in this embodiment are 0.00256°, 0.00510°, and 0.00743°, respectively. All three are less than 0.01°, indicating that the present invention has high stability in estimating the installation error angles of the two inertial navigation systems.

[0086] Since the actual installation error angles of the two inertial navigation systems are unknown, the calibration accuracy of this invention cannot be directly evaluated. Therefore, an indirect evaluation of the calibration accuracy of this embodiment is conducted using a vehicle-mounted test. Specifically, the output attitude of the high-precision inertial navigation system is used as the reference true value to calculate the attitude estimation error of the inertial navigation system to be evaluated. Based on this, compensation is made for the attitude estimation error caused by the installation error angle. The calibration accuracy of this embodiment is evaluated through the residual attitude estimation error. The main performance indicators of the inertial devices of the two inertial navigation systems used in this embodiment are as follows: Figure 4 As shown.

[0087] The installation error angle calibrated by the self-alignment method and the attitude estimation error after compensation for the installation error angle calibrated by this invention are as follows: Figure 5 As shown, it is evident that the three-axis attitude errors after compensation using the installation error angle calibrated by this invention are significantly smaller than those calibrated using the self-alignment method, proving that the installation error angle of this invention has high accuracy.

[0088] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., 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 method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information, characterized in that: The structure equipped with two inertial navigation systems is subjected to multi-angle transformations. At each angle, the data matrix output by the triaxial accelerometers of the two inertial navigation systems is acquired over a period of time, and the relative force of the two inertial navigation systems is calculated. The force comparison datasets of the two inertial navigation systems were obtained by multi-angle transformation; Based on the comparative force datasets of two inertial navigation systems, an information matrix to be optimized regarding the installation attitude error angle is constructed using physical relation equations; If the information matrix to be optimized is a singular matrix, repeat the above steps until the obtained information matrix to be optimized is a non-singular matrix. The comparison dataset based on two inertial navigation systems and A matrix of information to be optimized regarding the installation attitude error angle is constructed using physical relation equations. ; in, This is the accelerometer accuracy weight matrix. , For the first Accuracy weights of accelerometers at various angles; The information matrix to be optimized is decomposed, and the optimal coordinate transformation matrix is ​​calculated based on the decomposed matrix. The pitch installation error, roll installation error and heading installation error between the two inertial navigation systems are calculated based on the elements in the optimal coordinate transformation matrix, and the installation error angle calibration of the two inertial navigation systems is completed.

2. The method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information according to claim 1, characterized in that: In the Obtain from each angle The data matrix output by the three-axis accelerometer of the first inertial navigation system within the specified time. The data matrix output by the three-axis accelerometer of the second inertial navigation system ; and These represent the data output frequencies of the first and second inertial navigation systems, respectively.

3. The method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information according to claim 2, characterized in that: according to Calculate the specific force of the first inertial navigation system : according to Calculate the specific force of the first inertial navigation system : pass Sub-angle transformation to obtain the comparison dataset of the two inertial navigation systems. and .

4. The method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information according to claim 3, characterized in that: Information matrix to be optimized Decompose; Among them, matrix Each column is eigenvectors; matrices Each column is eigenvectors; matrices It is a diagonal matrix, with each element on the main diagonal being the information matrix to be optimized. The singular values ​​of .

5. The method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information according to claim 4, characterized in that: Calculate the optimal coordinate transformation matrix ; matrix for The matrix, based on the matrix elements in , Calculate the pitch installation error between the two inertial navigation systems. Roller installation error and heading installation error ; like ,but , , ; otherwise, , , .

6. The method for calibrating the installation error angle of two inertial navigation systems based on accelerometer information according to claim 1, characterized in that: Before starting the calibration, power on both inertial navigation systems and preheat them for a period of time.

7. A computer device / equipment / system, comprising a memory, a processor, and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 6.

8. A computer-readable storage medium having a computer program / instructions stored thereon, characterized in that: When the computer program / instructions are executed by the processor, they implement the steps of the method described in any one of claims 1 to 6.

9. A computer program product, comprising a computer program / instructions, characterized in that: When the computer program / instructions are executed by the processor, they implement the steps of the method described in any one of claims 1 to 6.

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