Method and device for calibrating angular dependence error of scale factor of micro-electro-mechanical gyroscope

Abstract

The application relates to a scale factor angle correlation error calibration method and device of a micro-electro-mechanical gyroscope. The method comprises the following steps: assembling the micro-electro-mechanical gyroscope on a turntable; taking the initial zero position of the turntable as a starting point, rotating the turntable forward and then reversely, and obtaining a first forward and reverse mode angle output sequence; calculating according to the first forward and reverse mode angle output sequence to obtain a constant coefficient of the scale factor angle correlation error; controlling the mode angle at different initial positions, rotating the turntable forward to a preset angle and then reversely to the preset angle, and obtaining a gyroscope forward and reverse output sequence and a second forward and reverse mode angle output sequence; fitting the mode angle and the drift coefficient through a fitting model according to the constant coefficient, the preset angle, the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence to obtain a fitting result; and compensating the scale factor error of the micro-electro-mechanical gyroscope based on the fitting result. The application can reduce the dynamic error of the gyroscope and improve the measurement precision.

Description

Technical Field

[0001] This invention relates to the field of microelectromechanical gyroscope technology, and in particular to a method and apparatus for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope. Background Technology

[0002] Inertial navigation systems provide precise position, velocity, and attitude data by measuring the spatial motion of a vehicle. This technology is widely used in applications such as high-spin projectiles, underwater vehicles, and positioning and orientation. Compared to non-autonomous navigation, inertial navigation offers advantages such as complete autonomy and strong environmental adaptability.

[0003] As a core component of the system, the performance of the gyroscope directly determines key indicators such as positioning and orientation accuracy in inertial navigation. Traditional systems often use electrostatic gyroscopes, two-optical gyroscopes, atomic gyroscopes, or hemispherical resonator gyroscopes to measure the angular motion of the carrier. However, these gyroscopes generally have limitations such as large size, heavy weight, and high cost.

[0004] Due to their advantages of miniaturization, low power consumption, and low cost, microelectromechanical gyroscopes (MEMS) are increasingly widely used in inertial navigation. MEMS gyroscopes operate in two modes: rate mode and rate integral mode. Compared to rate mode, rate integral mode offers advantages such as larger bandwidth and wider measurement range. In rate integral mode, the gyroscope's scaling factor error is typically assumed to be constant, and its angular correlation error is often ignored. However, in highly dynamic environments, the angular correlation error of the scaling factor can severely affect the gyroscope's measurement accuracy. For example, with an external angular velocity input of 100° / s, the scaling factor angular correlation error of a rate integral MEMS gyroscope is typically greater than 100ppm, resulting in an angular velocity measurement error of 36° / h. This error cannot be ignored and requires effective calibration and correction. Summary of the Invention

[0005] Therefore, it is necessary to provide a method and apparatus for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope that can perform high-precision calibration and achieve compensation fitting, in order to address the above-mentioned technical problems.

[0006] A method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope, the method comprising:

[0007] The microelectromechanical gyroscope is mounted on the turntable;

[0008] Starting from the initial zero position of the turntable, the turntable is rotated in the forward direction and then in the reverse direction to obtain the first forward and reverse mode angle output sequence; the constant coefficient of the scaling factor angle correlation error is obtained by calculating based on the first forward and reverse mode angle output sequence.

[0009] By controlling the mode angle at different initial positions, the turntable is rotated forward to a preset angle and then in the opposite direction to a preset angle to obtain the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence.

[0010] Based on the constant coefficient, the preset angle, the forward and reverse output sequence of the gyroscope, and the second forward and reverse mode angle output sequence, the mode angle and drift coefficient are fitted by a fitting model to obtain the fitting result;

[0011] The scaling factor error is compensated for based on the fitting results.

[0012] On the other hand, a scaling factor angle correlation error calibration device for a microelectromechanical gyroscope is also provided, comprising:

[0013] Assembly module, used to assemble the microelectromechanical gyroscope onto the turntable;

[0014] The constant coefficient calculation module is used to take the initial zero position of the turntable as the starting point, then rotate the turntable in the forward direction and then in the reverse direction to obtain the first positive and negative mode angle output sequence; and calculate the constant coefficient of the scaling factor angle correlation error based on the first positive and negative mode angle output sequence.

[0015] The output sequence calculation module is used to control the mode angle at different initial positions, then rotate the turntable forward to a preset angle and then in the opposite direction to a preset angle to obtain the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence.

[0016] The fitting module is used to fit the mode angle and drift coefficient using a fitting model based on the constant coefficient, the preset angle, the forward and reverse output sequence of the gyroscope and the second forward and reverse mode angle output sequence, and to obtain the fitting result.

[0017] An error compensation module is used to compensate the microelectromechanical gyroscope for scaling factor error based on the fitting result.

[0018] Compared with the prior art, the scaling factor angle correlation error calibration method and device for microelectromechanical gyroscopes provided by the present invention have the following beneficial effects:

[0019] This invention adopts a two-stage approach. First, starting from the initial zero position of the turntable, it acquires the first positive and negative mode shape angle output sequences, thereby locking the fixed offset component in the scaling factor angular correlation error and avoiding interference from fundamental errors in dynamic parameter fitting. Then, by controlling the mode shape angle at different initial positions, it acquires the gyroscope's positive and negative output sequences and the second positive and negative mode shape angle output sequences to fully capture the nonlinear law of scaling factor variation with mode shape angle. Through two-stage calibration of output parameters, it avoids matrix singularity problems caused by coefficient ambiguity, improves parameter estimation accuracy, and reduces error cross-interference. By fitting a model to determine the relationship between mode shape angle and drift coefficient, it eliminates the angular correlation of the scaling factor, reduces the dynamic error of the gyroscope, and improves the measurement accuracy of the gyroscope and inertial navigation system. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention, and those skilled in the art can obtain other related drawings based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating the scaling factor angle correlation error calibration method for the microelectromechanical gyroscope provided in Example 1;

[0022] Figure 2 This is a schematic diagram of the scaling factor angle correlation error curve of the measured microelectromechanical gyroscope provided in Example 1;

[0023] Figure 3 This is a schematic diagram of the scale factor angle correlation error repeatability curve fitted by the measured microelectromechanical gyroscope provided in Example 1;

[0024] Figure 4 This is a structural block diagram of the scaling factor angle correlation error calibration device for the microelectromechanical gyroscope provided in Example 2.

[0025] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that in this invention, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] It is understood that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0029] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0030] Example 1

[0031] like Figure 1 As shown, a method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope is provided, including the following steps:

[0032] Step 201: Assemble the microelectromechanical gyroscope onto the turntable.

[0033] Step 202: Starting from the initial zero position of the turntable, rotate the turntable forward and then in the reverse direction to obtain the first forward and reverse mode angle output sequence; calculate the constant coefficient of the scaling factor angle correlation error based on the first forward and reverse mode angle output sequence.

[0034] Step 203: Control the mode angle at different initial positions, then rotate the turntable forward to a preset angle and then in the opposite direction to a preset angle to obtain the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence.

[0035] Step 204: Based on the constant coefficients, preset angles, gyroscope forward and reverse output sequences, and second forward and reverse mode angle output sequences, fit the mode angles and drift coefficients using a fitting model to obtain the fitting results.

[0036] Step 205: Compensate for the scaling factor error of the microelectromechanical gyroscope based on the fitting results.

[0037] In the specific implementation of step 201, the turntable is a single-axis turntable; when the microelectromechanical gyroscope is assembled on the single-axis turntable, the sensitive axis of the microelectromechanical gyroscope is set upwards, and then the power is turned on for preheating.

[0038] It is understood that this invention can complete all data acquisition using only a single-axis turntable, eliminating the need for complex multi-dimensional attitude adjustments, thus reducing the precision requirements and cost of hardware equipment.

[0039] In the specific implementation of step 202, after preheating, the turntable is zeroed. Then, using the initial zero position of the turntable as the starting point, the turntable is moved at a preset angular velocity. Rotate in the forward direction and then in the reverse direction to obtain the first forward and reverse mode angle output sequence.

[0040] The first positive and negative mode angle output sequence includes a first positive mode angle output sequence and a first negative mode angle output sequence, wherein the turntable operates at a preset angular velocity. Rotate in the forward direction to obtain the first positive mode angle output sequence; then, the turntable rotates at the same preset angular velocity. Rotate in the opposite direction to obtain the first reverse mode angle output sequence.

[0041] The scaling factor is calculated based on the first positive mode angle output sequence and the first negative mode angle output sequence; then, the constant coefficient of the scaling factor angle correlation error is calculated based on the scaling factor and the gyroscope precession factor.

[0042] The expression for calculating constant coefficients is:

[0043] ;

[0044] In the formula, Indicates constant coefficients; Indicates the scale factor; This represents the gyroscope precession factor.

[0045] Furthermore, when the turntable rotates forward at a preset angular velocity and then in the reverse direction, the rotation angle satisfies that the change in mode angle is an integer multiple of 2π; the preset angular velocity is 10° / s to 100° / s.

[0046] In the specific implementation of step 203, the mode angle is controlled at different initial positions, and then the turntable is driven at a preset angular velocity. The gyroscope is rotated forward to a preset angle and then backward to a preset angle to obtain the forward and reverse output sequences and the second forward and reverse mode angle output sequences. The forward and reverse output sequences of the gyroscope include the forward output sequence and the reverse output sequence of the gyroscope; the second forward and reverse mode angle output sequences include the second forward mode angle output sequence and the second reverse mode angle output sequence.

[0047] Among them, the turntable is driven at a preset angular velocity Rotate forward to the preset angle Obtain the forward output sequence of the gyroscope. Second positive mode angle output sequence Then, the turntable moves at the same preset angular velocity. Rotate in the opposite direction to the preset angle Obtain the reverse output sequence of the gyroscope. Second reverse mode angle output sequence In the formula, This represents the number of sampling points.

[0048] In the specific implementation of step 204, a system of equations is first established, and the drift coefficient is estimated using the least squares method. , .

[0049] Then, a fitting model is constructed. The constant coefficients, preset angles, gyroscope forward and reverse output sequences, and second forward and reverse mode angle output sequences are substituted into the fitting model. The mode angles and estimated drift coefficients are fitted by the fitting model to obtain the fitting results.

[0050] The expression for the fitted model is:

[0051] ;

[0052] In the formula, This represents the forward and reverse output sequence of the gyroscope; Indicates the preset angle; , The drift coefficient represents the scaling factor angle correlation error; This represents a multiple of the mode shape angle, where... The value is selected based on the gyroscope scaling factor error characteristics; Indicates the mode angle output sequence; Indicates constant coefficients; This represents the gyroscope precession factor.

[0053] It is understandable that, through actual testing, it can be found that for microelectromechanical gyroscopes, the second and fourth angles of the scaling factor have significant correlation. Based on this, this embodiment provides the above-mentioned fitting model to compensate for the nonlinear error of the scaling factor and improve the measurement accuracy over a large angle range.

[0054] The fitting model outputs a curve as the fitting result. During error compensation, the mode shape angle under the current operating condition is obtained. Then, based on the fitted curve, the corresponding constant coefficients and drift coefficients are compensated to the output of the microelectromechanical gyroscope to complete the scaling factor error compensation of the microelectromechanical gyroscope.

[0055] In one embodiment, the superiority of the method proposed in this invention was verified through actual testing.

[0056] The microelectromechanical gyroscope was placed on a single-axis turntable with the sensitive axis facing upwards and allowed to rest for 40 minutes for preheating. Then, the angular correlation of the scaling factor was eliminated by rotating the turntable in multiples of 2π of the mode shape angle, and the constant coefficient of the scaling factor angular correlation error was isolated and calibrated. Next, the mode shape angle was controlled at different initial positions, and the turntable was rotated by a preset angle. Through measurements at multiple positions, the drift coefficient of the scaling factor angular correlation error was fitted. Finally, the constant coefficient and drift coefficient of the scaling factor angular correlation error were used to compensate for the gyroscope output.

[0057] The estimated results of the scaling factor angle correlation error coefficient of the measured microelectromechanical gyroscope are shown in Table 1. It can be seen from the table that the repeatability of the constant coefficients is within 10 ppm, which also proves that the rate integral microelectromechanical gyroscope has excellent integer scaling factor repeatability; the standard deviation of the drift coefficient error is also within 10 ppm, and the range is slightly larger, around 20 ppm.

[0058] Table 1

[0059]

[0060] The scaling factor angle correlation error curve of the measured microelectromechanical gyroscope fitting is shown below. Figure 2 As shown, the scaling factor exhibits a high angular correlation, reaching 630 ppm, necessitating high-precision calibration and compensation.

[0061] The repeatability curve of the scaling factor angle correlation error fitted by the measured microelectromechanical gyroscope is shown below. Figure 3 As shown, the repeatability of the scaling factor angle correlation error is within 40 ppm, which is 15 times less than the error before calibration, proving the effectiveness of the method.

[0062] It should be understood that, although this embodiment Figure 1 The steps are shown sequentially as indicated by the arrows, but they are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order in which these steps are performed; they can be executed in other orders. Figure 1 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0063] Example 2

[0064] Based on the scaling factor angle correlation error calibration method for microelectromechanical gyroscopes in Embodiment 1, this embodiment discloses a scaling factor angle correlation error calibration device for microelectromechanical gyroscopes, such as... Figure 4 As shown, the scaling factor angle correlation error calibration device for a microelectromechanical gyroscope includes: an assembly module 401, a constant coefficient calculation module 402, an output sequence calculation module 403, a fitting module 404, and an error compensation module 405, wherein:

[0065] Assembly module 401 is used to assemble the microelectromechanical gyroscope onto the turntable.

[0066] The constant coefficient calculation module 402 is used to take the initial zero position of the turntable as the starting point, then rotate the turntable in the forward direction and then in the reverse direction to obtain the first positive and negative mode angle output sequence; and calculate the constant coefficient of the scaling factor angle correlation error based on the first positive and negative mode angle output sequence.

[0067] The output sequence calculation module 403 is used to control the mode angle at different initial positions, then rotate the turntable forward to a preset angle and then in the opposite direction to a preset angle to obtain the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence.

[0068] The fitting module 404 is used to fit the mode angle and drift coefficient through the fitting model based on the constant coefficient, preset angle, gyroscope forward and reverse output sequence and second forward and reverse mode angle output sequence to obtain the fitting result.

[0069] The error compensation module 405 is used to compensate for the scaling factor error of the microelectromechanical gyroscope based on the fitting results.

[0070] In this embodiment, the specific working process and working principle of the assembly module 401, constant coefficient calculation module 402, output sequence calculation module 403, fitting module 404, and error compensation module 405 are the same as those in Embodiment 1, and therefore will not be described again in this embodiment. Each unit module can be implemented entirely or partially through software, hardware, or a combination thereof. Each unit module can be embedded in or independent of the processor in the computer device in hardware form, or it can be stored in the memory of the computer device in software form, so that the processor can call and execute the operations corresponding to the above unit modules.

[0071] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0072] 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.

[0073] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope, characterized in that, The method includes: The microelectromechanical gyroscope is mounted on the turntable; Starting from the initial zero position of the turntable, the turntable is rotated in the forward direction and then in the reverse direction to obtain the first forward and reverse mode angle output sequence; the constant coefficient of the scaling factor angle correlation error is obtained by calculating based on the first forward and reverse mode angle output sequence. By controlling the mode angle at different initial positions, the turntable is rotated forward to a preset angle and then in the opposite direction to a preset angle to obtain the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence. Based on the constant coefficient, the preset angle, the forward and reverse output sequence of the gyroscope, and the second forward and reverse mode angle output sequence, the mode angle and drift coefficient are fitted by a fitting model to obtain the fitting result; Based on the fitting results, the scaling factor error of the microelectromechanical gyroscope is compensated. The expression for calculating the constant coefficient is as follows: ； The expression for the fitted model is: ； In the formula, Indicates constant coefficients; Indicates the scale factor; Indicates the gyroscope precession factor; This represents the forward and reverse output sequence of the gyroscope; Indicates the preset angle; , The drift coefficient represents the scaling factor angle correlation error; Indicates a multiple of the mode shape angle; This represents the output sequence of mode angles.

2. The method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope according to claim 1, characterized in that, The turntable is a single-axis turntable; when the microelectromechanical gyroscope is assembled on the single-axis turntable, the sensitive axis of the microelectromechanical gyroscope is set upward.

3. The method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope according to claim 1 or 2, characterized in that, Starting from the initial zero position of the turntable, the turntable is rotated forward and then backward to obtain the first forward and reverse mode angle output sequence, including: Starting from the initial zero position of the turntable, the turntable is rotated forward at a preset angular velocity and then in the reverse direction to obtain the first forward and reverse mode angle output sequence.

4. The scaling factor angle correlation error calibration method for a microelectromechanical gyroscope according to claim 3, characterized in that, When the turntable is rotated forward at a preset angular velocity and then in the reverse direction, the rotation angle satisfies that the change in mode angle is an integer multiple of 2π.

5. The method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope according to claim 3, characterized in that, The preset angular velocity is 10° / s to 100° / s.

6. The method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope according to claim 3, characterized in that, The constant coefficients of the scaling factor angle correlation error are calculated based on the first positive and negative mode angle output sequence, including: The first positive and negative mode angle output sequences include a first positive mode angle output sequence and a first negative mode angle output sequence; The scaling factor is calculated based on the first positive mode angle output sequence and the first negative mode angle output sequence; then, the constant coefficient of the scaling factor angle correlation error is calculated based on the scaling factor and the gyroscope precession factor.

7. The method for calibrating the scaling factor angle correlation error of a microelectromechanical gyroscope according to any one of claims 4 to 6, characterized in that, The drift coefficients are estimated using the least squares method; The fitting model is used to fit the mode shape angle and the estimated drift coefficient to obtain the fitting results; During compensation, the mode angle under the current operating condition is obtained, and then based on the fitting result, the corresponding constant coefficients and drift coefficients are compensated to the output of the microelectromechanical gyroscope.

8. A scaling factor angle correlation error calibration device for a microelectromechanical gyroscope, characterized in that, The device includes: Assembly module, used to assemble the microelectromechanical gyroscope onto the turntable; The constant coefficient calculation module is used to take the initial zero position of the turntable as the starting point, then rotate the turntable in the forward direction and then in the reverse direction to obtain the first positive and negative mode angle output sequence; and calculate the constant coefficient of the scaling factor angle correlation error based on the first positive and negative mode angle output sequence. The output sequence calculation module is used to control the mode angle at different initial positions, then rotate the turntable forward to a preset angle and then in the opposite direction to a preset angle to obtain the gyroscope forward and reverse output sequence and the second forward and reverse mode angle output sequence. The fitting module is used to fit the mode angle and drift coefficient using a fitting model based on the constant coefficient, the preset angle, the forward and reverse output sequence of the gyroscope and the second forward and reverse mode angle output sequence, and to obtain the fitting result. An error compensation module is used to compensate the microelectromechanical gyroscope for scaling factor error based on the fitting result; In the constant coefficient calculation module, the constant coefficient calculation expression is: ； In the fitting module, the expression of the fitting model is: ； In the formula, Indicates constant coefficients; Indicates the scale factor; Indicates the gyroscope precession factor; This represents the forward and reverse output sequence of the gyroscope; Indicates the preset angle; , The drift coefficient represents the scaling factor angle correlation error; Indicates a multiple of the mode shape angle; This represents the output sequence of mode angles.

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