Temperature compensation system and method based on gyroscope driving modal oscillation amplitude

Abstract

The invention discloses a temperature compensation system and method based on gyroscope driving modal oscillation amplitude, the system comprises a detection module, a demodulation module, a decimation filtering module and a temperature compensation module, the detection module is connected with a gyroscope, a driving signal and a sensing signal are collected and input into the demodulation module, the demodulation module extracts an angular velocity signal in the sensing signal, and the decimation filtering module is connected with the temperature compensation module. The demodulation module outputs an angular velocity signal to the decimation filtering module, the angular velocity signal is processed by the decimation filtering module to obtain the angular velocity signal, and the angular velocity signal is transmitted to the temperature compensation module; the temperature compensation module comprises an amplitude detection circuit and a calculation module, the amplitude detection circuit processes an input driving signal to obtain the amplitude of the driving signal, and the calculation module performs operation processing based on the amplitude of the driving signal and the angular velocity signal to obtain an output signal of the gyroscope; a processing signal is directly output from the gyroscope, so that the compensation effect is good, and the zero offset of the gyroscope in a full-temperature environment is effectively improved; the whole circuit is simple, the process is simple and the processing efficiency is high.

Description

Technical Field

[0001] The present invention relates to the technical field of gyroscope temperature compensation, and in particular to a temperature compensation system and method based on the oscillation amplitude of a gyroscope drive mode. Background Art

[0002] A gyroscope is a precision measuring device whose performance is affected by many factors, temperature being a significant one. Temperature fluctuations can cause changes in the physical properties of sensitive components within the gyroscope (such as optical fiber), which in turn affects measurement accuracy. To mitigate this effect and improve measurement accuracy, the gyroscope requires temperature compensation. Several existing temperature compensation methods exist, including isolating the gyroscope from temperature fluctuations, using temperature sensors to monitor and compensate for gyroscope temperature, and employing neural network models to compensate for fiber optic gyroscope errors. However, existing temperature compensation circuits use a temperature sensor external to the gyroscope, which differs from the gyroscope's actual temperature. This limits the effectiveness of temperature compensation and results in poor compensation. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the present invention aims to provide a temperature compensation system and method based on the oscillation amplitude of the gyroscope drive mode.

[0004] In order to achieve the above object, the present invention provides the following technical solutions: A temperature compensation system based on the oscillation amplitude of a gyroscope drive mode includes a detection module, a demodulation module, an extraction and filtering module, and a temperature compensation module. The detection module is connected to the gyroscope, collects a drive signal and a sensing signal, and inputs them into the demodulation module. The demodulation module extracts an angular velocity signal from the sensing signal, and the demodulation module outputs the angular velocity signal to the extraction and filtering module. The extraction and filtering module filters out noise outside the target bandwidth, reduces the data rate, and then transmits the processed angular velocity signal to the temperature compensation module. The drive signal is also input into the temperature compensation module. The temperature compensation module includes an amplitude detection circuit and a calculation module. The amplitude detection circuit processes the input drive signal to obtain the amplitude of the drive signal. The calculation module performs calculations based on the amplitude of the drive signal and the angular velocity signal to obtain the output signal of the gyroscope.

[0005] In the present invention, preferably, the amplitude detection circuit includes a square unit, and the square unit squares the input drive signal and outputs the signal as a DC component and an AC component.

[0006] In the present invention, preferably, the amplitude detection circuit further includes a filtering unit, and the filtering unit is used to filter out the AC component output by the self-scaling unit and retain the DC component.

[0007] In the present invention, preferably, the calculation module performs a fourth-order polynomial operation for temperature compensation: ; ; ; Where Gyro is the angular velocity signal output by the extraction filter module, Gyro comp is the compensated gyroscope output, V0, an, bn, cn, dn, S0, as, bs, cs, ds are compensation coefficients, V represents amplitude, ZR represents zero bias, and S represents scale factor.

[0008] A temperature compensation method based on gyroscope driven modal oscillation amplitude includes the following steps: Collecting driving signals and sensing signals of the gyroscope; Extracting an angular velocity signal from the sensing signal and filtering it; The driving signal is successively subjected to self-scaling and low-pass filtering to obtain an amplitude signal of the driving signal; Perform fourth-order polynomial calculation on the angular velocity signal and the amplitude signal to obtain the compensated gyroscope output signal.

[0009] Compared with the prior art, the present invention has the following beneficial effects: The system of the present invention collects the driving signal and sensing signal of the driving mode, obtains the amplitude of the driving mode through a simple amplitude detection circuit, and finally obtains the digital output signal of the gyroscope through calculation. The processed signal is directly obtained from the gyroscope output, with good compensation effect, effectively improving the zero bias of the gyroscope in a full-temperature environment; and the overall circuit is streamlined, the processing process is simple, and the processing efficiency is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic structural diagram of the temperature compensation system based on the gyroscope-driven modal oscillation amplitude according to the present invention.

[0011] Figure 2 This is a schematic structural diagram of the temperature compensation module of the present invention.

[0012] Figure 3 This is a flow chart of the demodulation module and the extraction and filtering module of the present invention.

[0013] Figure 4 Schematic diagram of the zero-input gyro output G0 and amplitude output A measured at various temperature points in one embodiment.

[0014] Figure 5 Gyro output after compensation in one embodiment comp Schematic diagram of the amplitude output A. DETAILED DESCRIPTION

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0016] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0017] Please also see Figure 1 and Figure 2 A preferred embodiment of the present invention provides a temperature compensation system based on the oscillation amplitude of the gyroscope driving mode. Based on the linear relationship between the oscillation amplitude of the gyroscope driving mode and the temperature of the gyroscope, the system collects the driving signal and the sensing signal of the driving mode, collects the amplitude of the driving mode through a simple amplitude detection circuit, processes the sensing signal to obtain an angular velocity signal, and finally calculates the angular velocity signal and the amplitude signal to obtain the digital output signal of the temperature-compensated gyroscope.

[0018] The system specifically includes a detection module, a demodulation module, an extraction filter module, and a temperature compensation module. The detection module is connected to the gyroscope to collect the drive signal and the sensing signal. The steady-state response of the sensing signal is: , , k , represents the amplitude of the driving signal, represents the amplitude of the sensing detection signal, represents the detected angular velocity, Indicates the frequency of the drive detection signal, Indicates the phase shift of the drive detection signal, Indicates the frequency of the sensing detection signal, represents the phase of sensing detection, represents the mass of the drive shaft mass, Indicates the mass of the detection axis mass block, represents the quality factor of the sensing detection, t Represents time.

[0019] The driving signal is:

[0020] After capacitor-to-voltage conversion and analog-to-digital conversion, the drive signal and the sensing signal are input into the demodulation module for demodulation. The demodulation module performs synchronous demodulation, so the sensing signal is phase-shifted. The register in the demodulation module controls the phase of the sensing signal to be the same as the phase of the drive signal. The expression of the sensing signal after phase shift is: , like Figure 3 As shown, the demodulation process in the demodulation module is specifically as follows:

[0021]

[0022]

[0023]

[0024] Then the signal Input to the extraction filter module, and after low-pass filtering of the extraction filter module, the high-frequency signal is filtered out, and the angular velocity signal is finally obtained as , is input into the temperature compensation module, and the driving signal is also input into the temperature compensation module.

[0025] The temperature compensation module includes an amplitude detection circuit and a calculation module. The amplitude detection circuit processes the input drive signal to obtain the amplitude of the drive signal. The calculation module performs calculations based on the amplitude of the drive signal and the angular velocity signal to obtain the output signal of the gyroscope.

[0026] Specifically, the amplitude detection circuit mainly performs amplitude detection on the driving signal, which includes a self-squaring unit and a filtering unit. The self-squaring unit adopts a NAND gate structure, and outputs a DC component and an AC component after self-squaring the input driving signal. The DC component and the AC component are input into the filtering unit. The filtering unit filters out the AC component and retains the DC component. The DC component is the amplitude of the driving signal, which is passed to the calculation module.

[0027] Specifically, the calculation module finally performs the fourth-order polynomial operation for temperature compensation: ; ; ; Where Gyro is the angular velocity signal output by the extraction filter module, Gyro compis the compensated gyroscope output signal. V0, an, bn, cn, dn, S0, as, bs, cs, and ds are compensation coefficients measured through preliminary experiments and can be customized. V represents amplitude, ZR represents bias, and S represents scale factor. After calculation, the final temperature-compensated gyroscope output signal is obtained, which can effectively reflect the temperature changes of the gyroscope and improve the bias of the gyroscope in all temperature environments.

[0028] Specifically, the compensation coefficient fitting process is as follows: N points are uniformly selected between the expected minimum and maximum operating temperatures of the gyroscope, where N is greater than or equal to 5. At each temperature point, the gyroscope output G and amplitude measurement output A are recorded for each input, including zero, maximum, and minimum input (the maximum and minimum inputs depend on the expected operating range of the gyroscope). N sets of gyroscope output G corresponding to zero, maximum, and minimum inputs, as well as N sets of amplitude measurement output A corresponding to each temperature point, are obtained. The N zero inputs and N amplitude measurement outputs A are then fitted to a fourth-order polynomial to obtain the compensation coefficients V0, an, bn, cn, and dn. The compensation coefficients S0, as, bs, cs, and ds are obtained by fitting the average of the absolute values ​​of the maximum and minimum inputs at the N temperature points (the maximum and minimum inputs are assumed to be equal by default) and the N amplitude measurement outputs A to a fourth-order polynomial.

[0029] Specifically, in a specific embodiment, the operating temperature of the gyroscope is -40°C to 80°C, and -40°C, -20°C, 0°C, 20°C, 40°C, 60°C, and 80°C are taken as fitting temperature points between -40°C and 80°C, and the zero-input gyroscope output G and amplitude output A at each temperature point are measured, as shown in FIG. Figure 4 As shown in Table 1, the amplitude output A is used as the independent variable and the gyro output G is used as the variable to perform a fourth-order polynomial fitting to obtain the temperature compensation coefficients V0, an, bn, cn, and dn. Table 1:

[0030] Measure the gyro output G at the maximum / minimum input (taking ±500° / s as an example) at each simulated temperature point. max / G min And the amplitude output A (all are the average of multiple measurements). It is proposed that the gyro output under the maximum input after compensation corresponds to 7500000LSB, and the calculation is performed at each temperature point. Denoted as SF, as shown in Table 2 below: Table 2

[0031] The amplitude output A is used as the independent variable and SF is used as the variable to perform fourth-order polynomial fitting to obtain the temperature compensation coefficients S0, as, bs, cs, and ds, as shown in Table 3 below: Table 3

[0032] For the zero-input gyro output at each temperature point, use the previously calculated temperature compensation coefficient and calculate ZR, S according to the formula, as well as the compensated gyro output Gyro comp ,like Figure 5 The figure below compares bias stability before and after temperature compensation. Before compensation, the standard deviation of the zero-input gyro output was approximately 1978 LSBs, corresponding to 1978 / 7,500,000*500° / s=474° / h. After compensation, the standard deviation of the zero-input gyro output was approximately 332 LSBs, corresponding to 303 / 7,500,000*500° / s=79.68° / h, a decrease of 83.2% compared to before compensation.

[0033] Another preferred embodiment of the present invention provides a temperature compensation method based on the gyroscope drive mode oscillation amplitude, comprising the steps of: Collecting driving signals and sensing signals of the gyroscope; Extracting an angular velocity signal from the sensing signal and filtering it; The driving signal is successively subjected to self-scaling and low-pass filtering to obtain an amplitude signal of the driving signal; Perform fourth-order polynomial calculation on the angular velocity signal and the amplitude signal to obtain the compensated gyroscope output signal.

[0034] Specifically, the method utilizes the good linear relationship between the oscillation amplitude of the driving mode and the temperature of the gyroscope. By directly obtaining the driving signal of the gyroscope in the driving mode, the amplitude signal is extracted from it, and the sensing signal of the gyroscope is processed to extract the angular velocity signal. The amplitude signal is used to compensate the angular velocity signal, thereby making the angular velocity signal output by the gyroscope more accurate and having a good compensation effect, and can effectively improve the zero bias of the gyroscope in a full-temperature environment.

[0035] In some other preferred embodiments of the present invention, a computer-readable storage medium is provided, storing a computer program. When the computer program is executed by a processor, the processor executes the steps of the method described in the above embodiment.

[0036] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0037] The above description is a detailed description of the preferred embodiments of the present invention, but the embodiments are not intended to limit the scope of the patent application of the present invention. Any equivalent changes or modifications completed under the technical spirit suggested by the present invention should fall within the patent scope covered by the present invention.

Claims

1. A temperature compensation system based on the gyroscope driven modal oscillation amplitude, characterized in that: It includes a detection module, a demodulation module, an extraction filter module, and a temperature compensation module. The detection module is connected to the gyroscope, collects the driving signal and the sensing signal and inputs them into the demodulation module. The demodulation module extracts the angular velocity signal from the sensing signal. The demodulation module outputs the angular velocity signal to the extraction filter module. The extraction filter module filters out the noise outside the target bandwidth, reduces the data rate, and then transmits the processed angular velocity signal to the temperature compensation module. At the same time, the driving signal is also input into the temperature compensation module. The temperature compensation module includes an amplitude detection circuit and a calculation module. The amplitude detection circuit obtains the amplitude of the driving signal by processing the input driving signal. The calculation module performs calculation processing based on the amplitude of the driving signal and the angular velocity signal to obtain the output signal of the gyroscope.

2. The temperature compensation system based on gyroscope drive modal oscillation amplitude according to claim 1, characterized in that: The amplitude detection circuit comprises a square unit, which squares the input drive signal and outputs the signal as a direct current component and an alternating current component.

3. The temperature compensation system based on gyroscope drive modal oscillation amplitude according to claim 2, characterized in that: The amplitude detection circuit also includes a filtering unit, which is used to filter out the AC component output by the self-scaling unit and retain the DC component.

4. The temperature compensation system based on gyroscope drive modal oscillation amplitude according to claim 1, characterized in that: The calculation module performs a fourth-order polynomial operation for temperature compensation: ； ； ； Where Gyro is the angular velocity signal output by the decimation filter module, Gyro comp is the compensated gyroscope output, V0, an, bn, cn, dn, S0, as, bs, cs, ds are compensation coefficients, ZR represents zero bias, S represents scale factor, and V represents amplitude.

5. A method for temperature compensation system based on gyro drive modal oscillation amplitude according to any one of claims 1 to 4, characterized in that: Includes steps: Collecting driving signals and sensing signals of the gyroscope; Extracting an angular velocity signal from the sensing signal and filtering it; The driving signal is subjected to self-scaling and low-pass filtering in sequence to obtain an amplitude signal of the driving signal; The angular velocity signal and the amplitude signal are subjected to fourth-order polynomial calculation to obtain the compensated gyroscope output signal.

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