Fiber-optic gyroscope temperature modeling and compensating method based on double temperature sensors

Abstract

The invention discloses a fiber-optic gyroscope temperature modeling and compensating method based on double temperature sensors, which comprises the following steps: acquiring temperature data by using temperature sensors fixed on the inner side and the outer side of a fiber coil base, and calculating the time gradient and the space gradient of the temperature of a fiber coil as input information of a fiber-optic gyroscope temperature model. Then, setting acquisition parameters in the high-low temperature box, and recording the output, temperature and temperature change rate curve of the fiber-optic gyroscope; and according to data characteristics, segmenting the data, and performing multiple linear regression fitting by using each segment of data to establish a fiber-optic gyroscope temperature model. Secondly, calculating calibration factors of the gyroscope at various temperatures, and performing polynomial fitting to reduce nonlinearity; and finally, pre-processing the acquired temperature data, and substituting the pre-processed temperature data into the temperature model to calculate a real-time zero offset temperature compensation amount so as to complete online temperature compensation. And the performance stability and the measurement precision of the fiber-optic gyroscope in different temperature environments are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fiber optic gyroscopes, and in particular to a fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors. Background Art

[0002] As a high-precision, high-stability angular velocity sensor, fiber optic gyroscope has broad application prospects in many fields such as aerospace, navigation and positioning, and inertial guidance. However, the performance of fiber optic gyroscope is restricted by many environmental factors, especially the temperature factor. The change in temperature will not only cause the physical properties of the optical elements, mechanical structures and electronic devices in the fiber optic gyroscope to change, but also cause the fluctuation of parameters such as the optical path length and refractive index in the fiber optic gyroscope, thereby affecting its measurement accuracy and stability. Therefore, the temperature problem has become a key problem that restricts the fiber optic gyroscope from moving towards engineering practicality.

[0003] In order to solve the temperature problem of fiber optic gyroscopes, researchers have proposed a variety of methods. Among them, reasonable design and improvement of gyroscope structure is a basic method of fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors. By optimizing the external shape and internal structure of the gyroscope, the direct impact of temperature on the gyroscope performance is reduced. Another method of fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors is to add temperature control equipment inside the gyroscope, such as heating elements or refrigeration systems, to actively control the working temperature of the gyroscope to keep it within a relatively stable range. In addition, using software methods for temperature modeling and compensation is also a very effective means of fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors. This method establishes a mathematical model between fiber optic gyroscope performance and temperature, and corrects the output signal of the gyroscope in real time, thereby eliminating the impact of temperature on gyroscope performance.

[0004] The shortcomings of the existing technology, although there are many methods for solving the temperature problem of fiber optic gyroscopes, there are still some shortcomings. For example, although the method of reasonably designing and improving the gyroscope structure can reduce the impact of temperature on the performance of the gyroscope to a certain extent, it is often limited by factors such as the size, weight and cost of the gyroscope, and it is difficult to be widely used in engineering. Although the method of adding temperature control equipment can actively control the working temperature of the gyroscope, it will increase the complexity and energy consumption of the gyroscope, and the accuracy and stability of the temperature control system will also directly affect the performance of the gyroscope. Although the temperature modeling and compensation technology in the software method has become the mainstream method for solving the temperature problem of fiber optic gyroscopes, due to the complexity and nonlinear characteristics of fiber optic gyroscopes, it is still a huge challenge to establish an accurate temperature model. In addition, the update and maintenance of the temperature model also requires a large amount of experimental data and computing resources, which increases the difficulty and cost of engineering implementation. Therefore, how to further improve the temperature stability and measurement accuracy of fiber optic gyroscopes is still a technical problem that needs to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art. To achieve the above purpose, a fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors is adopted to solve the problems raised in the above background technology.

[0006] A temperature modeling and compensation method for an optical fiber gyroscope based on dual temperature sensors comprises the following steps:

[0007] Step S1, collecting temperature data based on a first temperature sensor and a second temperature sensor fixed on both sides of the optical fiber coil base, subtracting the current measurement value of the first temperature sensor from the measurement value at the previous preset time to obtain the time gradient T′(n) of the optical fiber coil temperature; and subtracting the measurement values ​​of the first temperature sensor and the second temperature sensor at the same time to obtain the spatial gradient ΔT(n) of the optical fiber coil temperature as the input information of the optical fiber gyroscope temperature model;

[0008] Step S2, fix the fiber optic gyroscope in a high and low temperature box, set acquisition parameters, start the gyroscope at room temperature, start the temperature box after the gyroscope temperature stabilizes, set the acquisition conditions and record data at the same time, finally obtain sample data, and obtain the fiber optic gyroscope output curve, temperature output curve and temperature change rate curve;

[0009] Step S3, dividing the data obtained in step S2 into nine segments according to the output data characteristics of the fiber optic gyroscope;

[0010] Step S4, using the segmented gyro full-temperature experimental data to perform parameter fitting of multiple linear regression using the data of each segment, obtain the model parameters under the corresponding temperature environment, and establish the fiber optic gyro temperature model;

[0011] Step S5, presetting parameters, collecting the original output of the gyro, calculating the gyro calibration factor at each temperature, performing polynomial fitting on the calibration factor, and reducing the nonlinearity of the calibration factor;

[0012] Step S6, preprocessing the collected temperature data, obtaining the time gradient and space gradient of the temperature by subtraction, substituting them into the fiber optic gyro temperature model calculated in step S4, obtaining the real-time zero bias temperature compensation, and then performing temperature compensation subtraction to complete the online temperature compensation.

[0013] As a further solution of the present invention: in step S1, the first temperature sensor and the second temperature sensor are both 18B20 temperature sensors, and are respectively fixed on the inner and symmetrical outer walls of the optical fiber coil base, the first temperature sensor is installed inside the optical fiber ring, and the second temperature sensor is installed on the outer wall of the optical fiber coil.

[0014] As a further solution of the present invention: the specific steps of collecting temperature data in step S1 include:

[0015] The time gradient T′(n) of the fiber coil temperature and the spatial gradient ΔT(n) of the fiber coil temperature are as follows:

[0016] T′(n)=T1(n)-T1(n-1);

[0017] ΔT(n)=T1(n)-T2(n);

[0018] Wherein, T1(n) and T2(n) are respectively the measurement values ​​of the first temperature sensor and the second temperature sensor at time n.

[0019] As a further solution of the present invention: the specific steps in step S2 include:

[0020] The fiber optic gyroscope was fixed in a high and low temperature box, the gyroscope sampling frequency was 100 Hz, the temperature sampling period was 1 s, and the temperature change rate was set to 1° / min;

[0021] Start the gyro at room temperature, start the incubator after the gyro temperature stabilizes, lower the temperature in the incubator to -40°C and let the gyro work at this temperature for 90 minutes, then raise the incubator to 60°C and let the gyro work at this temperature for 90 minutes, then lower the temperature in the incubator to room temperature, and end the test after the fiber optic gyro output becomes stable again;

[0022] The output data of the fiber optic gyroscope is smoothed for 100ms to obtain the output data of the fiber optic gyroscope, and then the temperature change rate is calculated to obtain sample data to obtain the fiber optic gyroscope output curve, temperature output curve, and temperature change rate curve.

[0023] As a further solution of the present invention: the specific steps in step S4 include:

[0024] When fitting the model parameters, the full-temperature test data of the fiber optic gyroscope is first segmented according to different temperature conditions, and then the parameters of each segment are fitted by multivariate linear regression to obtain the model parameters under the corresponding temperature environment;

[0025] When performing compensation, first calculate the relevant variables in real time, make data segment judgment, and then call the corresponding model parameters for compensation calculation. The temperature polynomial model is as follows:

[0026]

[0027] Among them, L0 is a constant term, T is relative temperature, dT / dt is the rate of change, A i and B j are the polynomial coefficients, ε is the random error, and i and j are the highest orders.

[0028] As a further solution of the present invention: the specific steps in step S5 include:

[0029] The fiber optic gyroscope was fixed in a high and low temperature box with a turntable. The sensitive axis of the gyroscope was parallel to the rotation axis of the turntable. The experimental temperature was set at 6 points: -40℃, -20℃, -0℃, +20℃, +40℃, and +60℃.

[0030] After the internal temperature of the gyro stabilized at each set temperature, the turntable was rotated in sequence with angular velocities of ±2.5° / s, ±4° / s, ±6.4° / s, ±10° / s, ±15° / s, ±30° / s, ±45° / s, and ±60° / s, respectively. The original output of the gyro was collected, the gyro calibration factor was calculated at each temperature, and the calibration factor was fitted with a polynomial.

[0031] As a further solution of the present invention: the specific steps in step S6 include:

[0032] Based on the single chip microcomputer, the collected temperature data is first preprocessed, and the time gradient and space gradient of the temperature are obtained by subtraction, which are substituted into the fiber optic gyro temperature model calculated in step S3 to obtain the real-time zero bias temperature compensation amount, and this data is sent to the FPGA for temperature compensation subtraction, thereby realizing online temperature compensation.

[0033] Compared with the prior art, the present invention has the following technical effects:

[0034] By adopting the above technical solution, the influence of temperature change rate on the output accuracy of the fiber optic gyroscope is analyzed, and an accurate temperature model and calculation method are given, which can effectively reduce the output error of the fiber optic gyroscope caused by temperature change;

[0035] The general formula of the temperature model of the fiber optic gyroscope is given through induction and summary. For different fiber optic gyroscopes, after the temperature chamber cycle test, the output data of the fiber optic gyroscope can be used to build a model according to the general model, and the parameters can be solved by the multivariate linear regression method to obtain an accurate temperature model with strong applicability.

[0036] The collected temperature data is preprocessed and substituted into the preset temperature model for calculation to obtain the real-time zero-bias temperature compensation amount, and the data is sent to FPGA for temperature compensation reduction, which can realize online temperature compensation with good real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings:

[0038] Figure 1 A schematic diagram of the steps of the modeling and compensation method of the embodiment disclosed in this application;

[0039] Figure 2 This is a schematic diagram of the installation of the temperature sensor sampling points of the embodiment disclosed in this application;

[0040] Figure 3 A gyro output curve diagram of an embodiment disclosed in the present application;

[0041] Figure 4 It is a temperature output curve diagram of the embodiment disclosed in this application;

[0042] Figure 5 It is a temperature change rate curve diagram of the embodiment disclosed in this application;

[0043] Figure 6 It is a full temperature curve diagram of the embodiment disclosed in this application;

[0044] Figure 7 It is a piecewise fitting curve diagram of the embodiment disclosed in this application;

[0045] Figure 8 This is a temperature compensation effect diagram of the embodiment disclosed in this application;

[0046] Fig. 9 A graph showing the relationship between the gyro calibration factor and the rotation speed curve at different temperatures of the embodiment disclosed in the present application;

[0047] Fig.10 The figure is a calibration factor and temperature curve diagram of the embodiment disclosed in this application. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0049] Please refer to Figure 1 In an embodiment of the present invention, a temperature modeling and compensation method of an optical fiber gyroscope based on dual temperature sensors includes the following steps:

[0050] Step S1, collecting temperature data based on a first temperature sensor and a second temperature sensor fixed on both sides of the optical fiber coil base, subtracting the current measurement value of the first temperature sensor from the measurement value at the previous preset time to obtain the time gradient T′(n) of the optical fiber coil temperature; and subtracting the measurement values ​​of the first temperature sensor and the second temperature sensor at the same time to obtain the spatial gradient ΔT(n) of the optical fiber coil temperature as the input information of the optical fiber gyroscope temperature model;

[0051] Step S11, in the specific implementation steps, the temperature sensor is installed:

[0052] like Figure 2 As shown, the figure is a schematic diagram of the installation of the temperature sensor sampling point; in step S1, the first temperature sensor and the second temperature sensor both use two 18B20 temperature sensors, and are respectively fixed on the inner and symmetrical outer walls of the optical fiber coil base, the first temperature sensor is installed inside the optical fiber ring, and the second temperature sensor is installed on the outer wall of the optical fiber coil.

[0053] Step S12: temperature data collection:

[0054] The time gradient T′(n) of the fiber coil temperature is obtained by subtracting the current measurement value of the first temperature sensor installed in step S11 from the measurement value of the previous moment (30 seconds interval). The spatial gradient ΔT(n) of the fiber coil temperature is obtained by subtracting the measurement values ​​of the first temperature sensor from the second temperature sensor at the same moment. This is used as the input information of the fiber optic gyroscope temperature model.

[0055] Among them, the time gradient T′(n) of the fiber coil temperature and the spatial gradient ΔT(n) of the fiber coil temperature are as follows:

[0056] T′(n)=T1(n)-T1(n-1);

[0057] ΔT(n)=T1(n)-T2(n);

[0058] Wherein, T1(n) and T2(n) are respectively the measurement values ​​of the first temperature sensor and the second temperature sensor at time n.

[0059] Step S2, fix the fiber optic gyroscope in a high and low temperature box, set acquisition parameters, start the gyroscope at room temperature, start the temperature box after the gyroscope temperature stabilizes, set the acquisition conditions and record data at the same time, finally obtain sample data, and obtain the fiber optic gyroscope output curve, temperature output curve and temperature change rate curve. The specific steps include:

[0060] like Figure 3 As shown, the figure is a gyro output curve diagram;

[0061] like Figure 4 As shown, the figure is a temperature output curve diagram;

[0062] like Figure 5 As shown, the figure is a temperature change rate curve diagram;

[0063] First, the fiber optic gyroscope is firmly fixed in a high and low temperature chamber. This is to ensure that the fiber optic gyroscope can remain stable during the experiment and is not disturbed by the external environment. In the experimental setup, the sampling frequency of the gyroscope is set to 100Hz, which means that the gyroscope will perform 100 data samples per second to obtain sufficiently dense data points for subsequent analysis. At the same time, the temperature sampling period is set to 1 second, that is, the temperature change in the temperature chamber is recorded once per second to ensure that the details of the temperature change can be captured. The temperature change rate is set to 1 degree Celsius per minute, which is a relatively slow change rate, which helps to more carefully observe the performance changes of the fiber optic gyroscope at different temperatures.

[0064] Next, start the fiber optic gyroscope at room temperature and let it run for a while until the temperature reaches a stable state. This is to ensure that the gyroscope has adapted to the current ambient temperature before the experiment begins, so as to avoid initial errors caused by temperature changes. After the gyroscope temperature stabilizes, start the high and low temperature box and start the temperature cycle experiment. First, lower the temperature in the incubator to -40 degrees Celsius and let the fiber optic gyroscope work at this temperature for 90 minutes. This low temperature environment helps to observe the performance of the gyroscope under extreme cold conditions. Then, gradually increase the temperature of the incubator to 60 degrees Celsius and let the gyroscope work at this temperature for another 90 minutes. The high temperature environment is used to test the stability and reliability of the gyroscope under high temperature conditions. Finally, lower the temperature in the incubator to room temperature, and wait for the output of the fiber optic gyroscope to reach a stable state again before ending the entire experimental process.

[0065] After the experiment, the output data of the fiber optic gyroscope needs to be processed and analyzed. First, the output data of the gyroscope is smoothed for 100 milliseconds to eliminate data fluctuations caused by noise or interference. The smoothed data will be used to draw the output curve of the fiber optic gyroscope to intuitively show the performance changes of the gyroscope at different temperatures. At the same time, the temperature change rate needs to be calculated to obtain more detailed sample data. These sample data will be used to draw the temperature output curve and the temperature change rate curve, so as to have a more comprehensive understanding of the performance of the fiber optic gyroscope under different temperature conditions.

[0066] Step S3, dividing the data obtained in step S2 into nine segments according to the output data characteristics of the fiber optic gyroscope, and the specific steps include:

[0067] Experimental data segmentation: The temperature effect error of the fiber optic gyroscope has different changing rules under different temperature conditions (for example, temperature is approximately stable and violently oscillating, temperature rise and fall, fast and slow temperature change rate). According to the output data characteristics of the fiber optic gyroscope, the data obtained in step S2 is divided into nine segments. The specific segmentation method is shown in Table 1 below;

[0068] Table 1

[0069] Number of segments Temperature change characteristics T dT / dt d(dT / dt)dt 1 Temperature is approximately stable Extreme value stability (-r，r) (-∞，+∞) 2 Cooling down and speeding up <![CDATA[T<T0]]> (-∞,r] (-∞，0) 3 Cooling down and slowing down <![CDATA[T<T0]]> (-∞,r] (0，+∞) 4 Heating and speeding up <![CDATA[T<T0]]> (r,+∞) (0，+∞) 5 Heating and slowing down <![CDATA[T<T0]]> (r,+∞) (-∞，0) 6 Heating and speeding up <![CDATA[T>T0]]> (r,+∞) (0，+∞) 7 Heating and slowing down <![CDATA[T>T0]]> (r,+∞) (-∞，0) 8 Cooling down and speeding up <![CDATA[T>T0]]> (-∞，-r] (-∞，0) 9 Cooling down and slowing down <![CDATA[T>T0]]> (-∞，-r] (0，+∞)

[0070] Step S4, establishing a fiber optic gyroscope temperature model:

[0071] like Figure 6 As shown, the figure is a full-temperature temperature curve diagram;

[0072] After the segmented gyro full-temperature experimental data is segmented through the above step S3, the parameters of the multivariate linear regression are respectively fitted using the data of each segment to obtain the model parameters under the corresponding temperature environment, and the fiber optic gyro temperature model is established. The specific steps include:

[0073] When fitting the model parameters, the full-temperature test data of the fiber optic gyroscope is first segmented according to different temperature conditions, and then the parameters of each segment are fitted by multivariate linear regression to obtain the model parameters under the corresponding temperature environment;

[0074] like Figure 7 As shown, the figure is a piecewise fitting curve diagram;

[0075] When performing compensation, first calculate the relevant variables in real time, make data segment judgment, and then call the corresponding model parameters for compensation calculation. The temperature polynomial model is as follows:

[0076]

[0077] Among them, L0 is a constant term, T is relative temperature, dT / dt is the rate of change, Ai and B j are the polynomial coefficients, ε is the random error, and i and j are the highest orders.

[0078] Step S5, temperature error compensation of fiber optic gyro calibration factor:

[0079] In this embodiment, Figure 8 As shown, the figure is a temperature compensation effect diagram;

[0080] Preset parameters, collect the original output of the gyro, calculate the gyro calibration factor at each temperature, perform polynomial fitting on the calibration factor, and reduce the nonlinearity of the calibration factor. The specific steps include:

[0081] like Fig. 9 As shown, the figure shows the relationship between the gyro calibration factor and the rotation speed curve at different temperatures;

[0082] The fiber optic gyroscope was fixed in a high and low temperature box with a turntable. The sensitive axis of the gyroscope was parallel to the rotation axis of the turntable. The experimental temperature was set at 6 points: -40℃, -20℃, -0℃, +20℃, +40℃, and +60℃.

[0083] like Fig.10 As shown, the figure shows the calibration factor and temperature curve;

[0084] After the internal temperature of the gyro stabilized at each set temperature, the turntable was rotated in sequence with angular velocities of ±2.5° / s, ±4° / s, ±6.4° / s, ±10° / s, ±15° / s, ±30° / s, ±45° / s, and ±60° / s, respectively. The original output of the gyro was collected, the gyro calibration factor was calculated at each temperature, and the calibration factor was fitted with a polynomial.

[0085] Step S6: Online temperature compensation:

[0086] In the signal processing board of the fiber optic gyroscope, the single-chip microcomputer C8051 is responsible for temperature data acquisition and online temperature compensation solution. The acquired temperature data is preprocessed, and the time gradient and space gradient of the temperature are obtained by subtraction. The time gradient and space gradient are substituted into the fiber optic gyroscope temperature model calculated in step S4 to obtain the real-time zero-bias temperature compensation amount, and then the temperature compensation is subtracted to complete the online temperature compensation.

[0087] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents, and all should be included in the scope of protection of the present invention.

Claims

1. A temperature modeling and compensation method for an optical fiber gyroscope based on dual temperature sensors, characterized in that: The following steps are involved: Step S1, collecting temperature data based on a first temperature sensor and a second temperature sensor fixed on both sides of the optical fiber coil base, subtracting the current measurement value of the first temperature sensor from the measurement value at the previous preset time to obtain the time gradient T′(n) of the optical fiber coil temperature; and subtracting the measurement values ​​of the first temperature sensor and the second temperature sensor at the same time to obtain the spatial gradient ΔT(n) of the optical fiber coil temperature as the input information of the optical fiber gyroscope temperature model; Step S2, fix the fiber optic gyroscope in a high and low temperature box, set acquisition parameters, start the gyroscope at room temperature, start the temperature box after the gyroscope temperature stabilizes, set the acquisition conditions and record data at the same time, finally obtain sample data, and obtain the fiber optic gyroscope output curve, temperature output curve and temperature change rate curve; Step S3, dividing the data obtained in step S2 into nine segments according to the output data characteristics of the fiber optic gyroscope; Step S4, using the segmented gyro full-temperature experimental data to perform parameter fitting of multiple linear regression using the data of each segment, obtain the model parameters under the corresponding temperature environment, and establish the fiber optic gyro temperature model; Step S5, presetting parameters, collecting the original output of the gyro, calculating the gyro calibration factor at each temperature, performing polynomial fitting on the calibration factor, and reducing the nonlinearity of the calibration factor; Step S6, preprocessing the collected temperature data, obtaining the time gradient and space gradient of the temperature by subtraction, substituting them into the fiber optic gyro temperature model calculated in step S4, obtaining the real-time zero bias temperature compensation, and then performing temperature compensation subtraction to complete the online temperature compensation.

2. The fiber optic gyro temperature modeling and compensation method based on dual temperature sensors according to claim 1, characterized in that: In step S1, the first temperature sensor and the second temperature sensor are both 18B20 temperature sensors, and are respectively fixed to the inner and symmetrical outer walls of the optical fiber coil base. The first temperature sensor is installed inside the optical fiber ring, and the second temperature sensor is installed on the outer wall of the optical fiber coil.

3. The fiber optic gyro temperature modeling and compensation method based on dual temperature sensors according to claim 2, characterized in that: The specific steps of collecting temperature data in step S1 include: The time gradient T′(n) of the fiber coil temperature and the spatial gradient ΔT(n) of the fiber coil temperature are as follows: T ′ (n)=T1(n)-T1(n-1); ΔT(n)=T1(n)-T2(n); Wherein, T1(n) and T2(n) are respectively the measurement values ​​of the first temperature sensor and the second temperature sensor at time n.

4. The fiber optic gyro temperature modeling and compensation method based on dual temperature sensors according to claim 1, characterized in that: The specific steps in step S2 include: The fiber optic gyroscope was fixed in a high and low temperature box, the gyroscope sampling frequency was 100 Hz, the temperature sampling period was 1 s, and the temperature change rate was set to 1° / min; Start the gyro at room temperature, start the incubator after the gyro temperature stabilizes, lower the temperature in the incubator to -40°C and let the gyro work at this temperature for 90 minutes, then raise the incubator to 60°C and let the gyro work at this temperature for 90 minutes, then lower the temperature in the incubator to room temperature, and end the test after the fiber optic gyro output becomes stable again; The output data of the fiber optic gyroscope is smoothed for 100ms to obtain the output data of the fiber optic gyroscope, and then the temperature change rate is calculated to obtain sample data to obtain the fiber optic gyroscope output curve, temperature output curve, and temperature change rate curve.

5. The fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors according to claim 1, characterized in that: The specific steps in step S4 include: When fitting the model parameters, the full-temperature test data of the fiber optic gyroscope is first segmented according to different temperature conditions, and then the parameters of each segment are fitted by multivariate linear regression to obtain the model parameters under the corresponding temperature environment; When performing compensation, first calculate the relevant variables in real time, make data segment judgment, and then call the corresponding model parameters for compensation calculation. The temperature polynomial model is as follows: Among them, L0 is a constant term, T is relative temperature, dT / dt is the rate of change, A i and B j are the polynomial coefficients, ε is the random error, and i and j are the highest orders.

6. The fiber optic gyro temperature modeling and compensation method based on dual temperature sensors according to claim 1, characterized in that: The specific steps in step S5 include: The fiber optic gyroscope was fixed in a high and low temperature box with a turntable. The sensitive axis of the gyroscope was parallel to the rotation axis of the turntable. The experimental temperature was set at 6 temperature points: -40℃, -20℃, -0℃, +20℃, +40℃, and +60℃. After the internal temperature of the gyro stabilized at each set temperature, the turntable was rotated in sequence with angular velocities of ±2.5° / s, ±4° / s, ±6.4° / s, ±10° / s, ±15° / s, ±30° / s, ±45° / s, and ±60° / s, respectively. The original output of the gyro was collected, the gyro calibration factor was calculated at each temperature, and the calibration factor was fitted with a polynomial.

7. The fiber optic gyroscope temperature modeling and compensation method based on dual temperature sensors according to claim 1, characterized in that: The specific steps in step S6 include: Based on the single chip microcomputer, the collected temperature data is first preprocessed, and the time gradient and space gradient of the temperature are obtained by subtraction, which are substituted into the fiber optic gyro temperature model calculated in step S3 to obtain the real-time zero bias temperature compensation amount, and this data is sent to the FPGA for temperature compensation subtraction, thereby realizing online temperature compensation.

Images