Optical fiber coil testing method based on semiconductor thermostat and semi-automatic parameter adjustment

Abstract

The invention discloses an optical fiber coil test method based on a semiconductor thermostat and semi-automatic parameter adjustment, which comprises the following steps: based on the Shupe effect of an optical fiber coil, acquiring output data of the optical fiber coil through semi-automatic parameter adjustment and a rapid temperature change process; establishing a performance evaluation system for the optical fiber coil; obtaining an evaluation index according to the collected output data, wherein the evaluation index comprises a Shupe coefficient and a nonlinear coefficient; and judging that the optical fiber coil meets a preset requirement according to the obtained evaluation index, and evaluating that the optical fiber coil is qualified. By evaluating the performance of the optical fiber coil, the production efficiency of the optical fiber gyroscope can be effectively improved, and the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of optical technology, and in particular to an optical fiber coil testing method based on a semiconductor constant temperature box and semi-automatic parameter adjustment. Background Art

[0002] Fiber optic gyroscope is an instrument for measuring angular velocity. The measurement of angular velocity by interferometric fiber optic gyroscope is characterized by the size of the non-different phase difference caused by the two beams of light propagating in the fiber optic ring in the rotation of the fiber optic gyroscope itself. Gyroscope is a device that is sensitive to angular motion relative to inertial space. As an important inertial sensor, it is used to measure the attitude and angular velocity of the moving carrier and is the core component of the inertial system.

[0003] In the production process of fiber optic gyroscopes, there is a lack of an efficient and accurate fiber optic coil testing system to accurately evaluate the performance of the fiber optic coil before it is assembled into a complete fiber optic gyroscope.

[0004] The shortcoming of the existing technology is that there is no suitable testing method to effectively collect the output data of the optical fiber coil and establish a performance evaluation system, which limits the improvement of the production efficiency and the reduction of the cost of the optical fiber gyroscope. 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 coil testing method based on a semiconductor constant temperature box and semi-automatic parameter adjustment is adopted to solve the problems raised in the above background technology.

[0006] A method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment, comprising:

[0007] Follow these steps:

[0008] Step S1, based on the Shupe effect of the optical fiber coil, the output data of the optical fiber coil is collected through semi-automatic parameter adjustment and rapid temperature change process;

[0009] Step S2, establishing a performance evaluation system for optical fiber coils;

[0010] Step S3, obtaining evaluation indicators according to the collected output data, wherein the evaluation indicators include Shupe coefficient and nonlinear coefficient;

[0011] Step S4: According to the obtained evaluation index, it is determined that it meets the preset requirements, and the optical fiber coil is evaluated as qualified.

[0012] As a further solution of the present invention: the specific steps in step S1 include:

[0013] Step S11, build the test system: place the detection device horizontally in the incubator and connect it to the evaluation system test platform, power it with a DC power supply, and power it on after checking that the wiring is correct;

[0014] Step S12, parameter adjustment: open the optical fiber coil parameter adjustment software, input the coil ring number and generate a file directory; connect the serial port and adjust the parameters according to the software prompts; the software automatically saves the parameters and writes them into the hardware circuit, and after completion, close the incubator cover;

[0015] Step S13, collecting the output data of the optical fiber coil at room temperature: opening the temperature box control software, setting the temperature measurement and constant temperature setting;

[0016] Keep the temperature box at 25°C and open the fiber coil measurement software after the temperature stabilizes;

[0017] Enter the coil number and generate a file directory, start measuring 10 minutes of normal temperature data, and calculate the optical fiber coil calibration factor K at normal temperature according to the formula:

[0018] K = F / ω;

[0019] Wherein, K is the calibration factor of the optical fiber coil at room temperature; F is the average value of the output data of the optical fiber coil at room temperature within 10 minutes, in LSB; ω is the celestial component of the local earth's rotation angular velocity;

[0020] Step S14, rapid temperature change measurement: set the temperature of the incubator to 20°C and maintain it for 30 minutes to stabilize the temperature of the optical fiber coil;

[0021] Set the temperature change process of the incubator, including constant temperature stages of 20℃, -5℃, 35℃ and 20℃, and a temperature change rate of 1℃ / min;

[0022] Start the temperature change process and open the fiber coil measurement software for data acquisition. The test lasts for 135 minutes. After the test, stop the measurement and turn off the software and the temperature chamber power.

[0023] Step S15, evaluate the test results: import data and calculate the Shupe coefficient, using the optical fiber coil performance evaluation software; set the basic parameters of the coil, including loop length, outer diameter and calibration factor; import the temperature setting file and measurement data, and the software automatically calculates the relevant parameters and Shupe coefficient; the smaller the Shupe coefficient, the better the performance of the optical fiber coil, and the Shupe coefficient is required to be ≤1; in the "Coil Curve Modeling and Compensation" interface of the software, import the 1s smoothed data of the rapid temperature change measurement, and calculate the nonlinear coefficient KNL, the formula is:

[0024] K NL =S C / B S ;

[0025] Where: K NL is the nonlinear coefficient, and the index system requires K NL ≤1.5; S C is the standard deviation after temperature compensation; B S is the zero bias stability of the coil at room temperature, calculated from the measurement data at room temperature.

[0026] As a further solution of the present invention: the specific steps of adjusting the parameters of the optical fiber coil in step S12 include:

[0027] The first step is to measure the special value frequency:

[0028] Obtain the characteristic frequency reference value in the automatic parameter tuning module, and verify its accuracy in the manual parameter tuning module;

[0029] Step 2: Coarse adjustment of half-wave voltage:

[0030] Obtain the rough adjustment reference value of the half-wave voltage in the automatic parameter adjustment module, then make fine adjustments in the manual parameter adjustment module, and observe the PIN waveform effect to obtain the best value;

[0031] Step 3: First bias adjustment:

[0032] Obtain reference values ​​for positive and negative terminal adjustments in the automatic parameter adjustment module, and make fine adjustments in the manual parameter adjustment module to obtain a better PERR waveform;

[0033] Step 4: Fine-tune the half-wave voltage:

[0034] Obtain the half-wave voltage fine-tuning reference value in the automatic parameter adjustment module, and then make fine adjustments in the manual parameter adjustment module to obtain a better PERR waveform;

[0035] Step 5: Modulation mode selection:

[0036] Select the modulation type of the fiber optic gyroscope in the automatic parameter adjustment module;

[0037] Step 6: Secondary bias adjustment:

[0038] Fine-tune the positive and negative ends again to obtain a better PERR waveform, which supplements or verifies the third step;

[0039] Step 7: Closed-loop test:

[0040] After selecting the corresponding option, conduct a test and observe the fluctuations in SERR and PERR data; if there is no drastic fluctuation, save the data; if there is, perform a reverse operation and repeat the above steps.

[0041] As a further solution of the present invention: the specific steps in step S13 include:

[0042] The test data is saved in the form of "temperature chamber test data.txt" to a fixed path in the folder where this application is located. After each measurement, the file needs to be saved to another location to prevent it from being overwritten by data generated by subsequent tests.

[0043] As a further solution of the present invention: the specific steps in step S14 include:

[0044] The data file used is derived from the 1s smoothed data file obtained in the previous step;

[0045] If you obtain data files from other paths, you must ensure that the format of the file content is consistent with the content format of the corresponding file obtained from the software, otherwise the display analysis will not obtain correct results.

[0046] Compared with the prior art, the present invention has the following technical effects:

[0047] By adopting the above technical solution, the output data of the optical fiber coil is collected through semi-automatic parameter adjustment and rapid temperature change process based on the Shupe effect of the optical fiber coil, and its evaluation indexes: Shupe coefficient S and nonlinear coefficient KNL are quickly obtained. Before the optical fiber coil is assembled into a complete optical fiber gyroscope, the present invention completes the output data collection of the optical fiber coil and establishes a performance evaluation system for the optical fiber coil, which can effectively improve the production efficiency of the optical fiber gyroscope and reduce the production cost.

[0048] Based on high-precision semiconductor constant temperature box and semi-automatic parameter adjustment method, the parameter model setting of the optical fiber coil is established quickly and accurately, and the output data of the optical fiber coil is collected through the rapid temperature change process, and the evaluation index Shupe coefficient and nonlinear coefficient are quickly obtained. It has strong applicability and can be extended to other BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings:

[0050] Figure 1 A schematic diagram of the steps of the optical fiber coil testing method according to the embodiment disclosed in the present application;

[0051] Figure 2 This is a structural block diagram of the evaluation and testing system platform of the embodiment disclosed in this application;

[0052] Figure 3 This is a schematic diagram of the interface of the optical fiber coil parameter adjustment software of the embodiment disclosed in this application;

[0053] Figure 4 This is a schematic diagram of the interface of the temperature box control software of the embodiment disclosed in this application;

[0054] Figure 5This is a schematic diagram of the interface of the optical fiber coil measurement software of the embodiment disclosed in this application;

[0055] Figure 6 This is a schematic diagram of the interface of the optical fiber coil evaluation software according to the embodiment disclosed in the present application;

[0056] Figure 7 This is a schematic diagram of the measurement results of the scale factor of a certain optical fiber coil according to the embodiment disclosed in this application;

[0057] Figure 8 This is a schematic diagram of the temperature variation measurement results of a certain optical fiber coil according to the embodiment disclosed in this application;

[0058] Fig. 9 This is a schematic diagram of a certain optical fiber coil curve and nonlinear coefficient measurement result diagram of an embodiment disclosed in this application. DETAILED DESCRIPTION

[0059] 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.

[0060] Please refer to Figure 1 and Figure 2 In an embodiment of the present invention, a method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment includes the following steps:

[0061] Step S1: Based on the Shupe effect of the optical fiber coil, the output data of the optical fiber coil is collected through semi-automatic parameter adjustment and rapid temperature change process. The specific steps include:

[0062] Step S11, build the test system: place the detection device horizontally in the incubator and connect it to the evaluation system test platform. The DC power supply is ±5V dual-circuit power supply, and power is turned on after checking that the wiring is correct; the test system hardware includes a digital oscilloscope, a DC power supply, a fiber optic coil detection device, and a high-precision semiconductor constant temperature box, and the software includes the optical fiber "Fiber Optic Coil Parameter Adjustment Software", "Incubator Control Software", "Light Coil Measurement Software" and "Fiber Optic Coil Evaluation Software".

[0063] Step S12: Figure 3 As shown, parameter adjustment: open the "Fiber Optic Coil Parameter Adjustment Software", enter the coil ring number, and click the "Generate File Directory" button; connect the serial port and adjust the parameters according to the software prompts. The method is as follows:

[0064] The parameter adjustment method adopts a semi-automatic parameter adjustment method, that is, combining the manual parameter adjustment module with the automatic parameter adjustment module, and using the high precision of the manual parameter adjustment method and the high speed of the fully automatic parameter adjustment method to achieve a compromise between the two parameter adjustment methods, ensuring high precision and fast parameter adjustment. The specific steps are as follows:

[0065] Step 1: Measure the characteristic frequency; obtain the reference value of the characteristic frequency in the automatic parameter adjustment module. After a large number of experiments, the accuracy of the reference value is verified to be high. If you have doubts about the accuracy of the value, you can verify the accuracy of the value in the manual parameter adjustment module according to the steps described in the manual parameter adjustment.

[0066] Step 2: Coarse adjustment of half-wave voltage; obtain the reference value of coarse adjustment of half-wave voltage in the automatic parameter adjustment module, and fine-tune the half-wave voltage value in the manual parameter adjustment module. Then click the "Send" button to observe the effect of the PIN waveform to obtain a better half-wave voltage value.

[0067] Step 3: First bias adjustment; obtain the positive end adjustment setting value and the negative end adjustment reference value in the automatic parameter adjustment module, and fine-tune the positive end adjustment and the negative end adjustment in the manual parameter adjustment module to obtain a better PERR waveform.

[0068] Step 4: Fine-tune the half-wave voltage; obtain the half-wave voltage fine-tuning reference value in the automatic parameter adjustment module, and fine-tune the half-wave voltage value in the manual parameter adjustment module to obtain a better PERR waveform.

[0069] Step 5: Modulation mode selection: Select the modulation type of the fiber optic gyroscope in the automatic parameter adjustment module.

[0070] Step 6: Secondary bias adjustment; obtain the positive end adjustment setting value and the negative end adjustment reference value in the automatic parameter adjustment module, and fine-tune the positive end adjustment and the negative end adjustment in the manual parameter adjustment module to obtain a better PERR waveform.

[0071] Step 7: Closed loop test; After selecting the corresponding option, click the "Test" button. After powering on again, observe whether the SERR and PERR data have drastic fluctuations. If not, click "Finish" to save the data; if so, you can choose to reverse REV = 0 and repeat the above operation.

[0072] After the adjustment is completed, the software will automatically save the relevant parameters and write them into the hardware circuit of the detection device. After the adjustment is completed, close the upper cover of the temperature chamber;

[0073] Step S13: Figure 4 As shown, collect the output data of the optical fiber coil at room temperature: open the "Incubator Control Software", enter the measured coil number in the "Temperature Measurement" interface and generate a file directory, connect the serial port, and set the incubator to 25°C in the "Constant Temperature Setting" interface;

[0074] When the temperature displayed by the incubator is stable within the range of 25℃±0.5℃, open the "Fiber Optic Coil Measurement Software", enter the coil number and generate a file directory, click the "Start" button to start the measurement, and stop the test after measuring a set of 10 minutes of room temperature coil data. Calculate the room temperature calibration factor K of the fiber optic coil according to formula (1):

[0075] K=F / ω (1)

[0076] Where: K is the calibration factor of the optical fiber coil at room temperature; F is the average value of the output data of the optical fiber coil at room temperature within 10 minutes, in LSB; ω is the celestial component of the local earth's rotation angular velocity;

[0077] The test data is saved in the form of "temperature chamber test data.txt" to a fixed path in the folder where this application is located. After each measurement, the file needs to be saved to another location to prevent it from being overwritten by data generated by subsequent tests.

[0078] Step S14: Figure 5 As shown, rapid temperature change measurement:

[0079] The temperature of the incubator is set to a constant temperature of 20°C. Since the temperature change of the optical fiber coil in the detection device will have a lag, the incubator is kept at 20°C for 30 minutes to allow the temperature of the optical fiber coil to stabilize.

[0080] Set the temperature change process of the incubator, open the "Incubator Control Software", press 20℃ (maintain 5min) → -5℃ (maintain 20min) → 35℃ (maintain 20min) → 20℃ (maintain 10min) in the "Temperature Change Setting" interface, and set the temperature change rate to 1℃ / min. The default number of cycles is 1, which means no cycle. After the incubator is kept for 30min, click the "Start" button in the "Temperature Change Setting" interface of the "Incubator Control Software" to start the temperature change process;

[0081] Switch to the "Fiber Optic Coil Measurement Software", enter the coil number and click the "Generate File Directory" button. The data file used comes from the 1s smoothed data file obtained in the previous step.

[0082] If you obtain data files from other paths, you must ensure that the format of the file content is consistent with the content format of the corresponding file obtained from the software, otherwise the display analysis cannot obtain correct results. Click the "Start" button to start the rapid temperature measurement. The test process is 135 minutes in total;

[0083] After the test is completed, click the "Stop" button in the "Fiber Optic Coil Measurement Software" to end the rapid temperature change measurement, close the "Incubator Control Software", and turn off the power of the incubator;

[0084] Step S15: Figure 6 , 7 , 8 and 9 show the evaluation test results:

[0085] Import data and calculate Shupe coefficient, open the "Optical Fiber Coil Performance Evaluation Software", create a file directory in the "Optical Fiber Coil Basic Parameters" interface that is consistent with the file path of the quick test results, and set the basic parameters of the coil including the coil loop length, outer diameter and calibration factor;

[0086] The temperature change process input can manually input the relevant parameters or click the "Import" button to import the "Temperature Setting.txt" file generated by the "Thermostat Control Software";

[0087] Click the "Import Measurement Data" button to import the 1s smoothed output data collected by the "Fiber Optic Coil Measurement Software". The software automatically calculates the relevant parameters and obtains the Shupe coefficient, an important evaluation parameter of the fiber optic coil. This coefficient is obtained through the least squares linear fitting method and reflects the relationship between the fiber optic coil output and the temperature rate. The unit is "° / h / (℃ / min)".

[0088] The smaller the Shupe coefficient is, the less the fiber coil is affected by temperature changes and the better its performance is. The index system requires the Shupe coefficient to be ≤1;

[0089] Switch to the "Coil Curve Modeling and Compensation" interface of the software, enter the calibration factor and click "Import Modeling Data" to import the 1s smoothed data of the rapid temperature change measurement, and calculate the nonlinear coefficient of the coil according to formula (2).

[0090] K NL =S C / B S (2)

[0091] Where: K NL is the nonlinear coefficient, and the index system requires K NL ≤1.5; SC is the standard deviation after temperature compensation; B S is the zero bias stability of the coil at room temperature, calculated from the measurement data at room temperature.

[0092] Step S2, establishing a performance evaluation system for optical fiber coils;

[0093] Step S3, obtaining evaluation indicators according to the collected output data, wherein the evaluation indicators include Shupe coefficient and nonlinear coefficient;

[0094] Step S4: According to the obtained evaluation index, it is determined that it meets the preset requirements, and the optical fiber coil is evaluated as qualified.

[0095] The Shupe coefficient and the nonlinear coefficient obtained according to the above steps meet the requirements at the same time, that is, the optical fiber coil is evaluated as qualified.

[0096] 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 within the scope of protection of the present invention.

Claims

1. A method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment, characterized in that: The following steps are involved: Step S1, based on the Shupe effect of the optical fiber coil, the output data of the optical fiber coil is collected through semi-automatic parameter adjustment and rapid temperature change process; Step S2, establishing a performance evaluation system for optical fiber coils; Step S3, obtaining evaluation indicators according to the collected output data, wherein the evaluation indicators include Shupe coefficient and nonlinear coefficient; Step S4: According to the obtained evaluation index, it is determined that it meets the preset requirements, and the optical fiber coil is evaluated as qualified.

2. According to claim 1, a method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment is characterized in that: The specific steps in step S1 include: Step S11, build the test system: place the detection device horizontally in the incubator and connect it to the evaluation system test platform, power it with a DC power supply, and power it on after checking that the wiring is correct; Step S12, parameter adjustment: open the optical fiber coil parameter adjustment software, input the coil ring number and generate a file directory; connect the serial port and adjust the parameters according to the software prompts; the software automatically saves the parameters and writes them into the hardware circuit, and after completion, close the incubator cover; Step S13, collecting the output data of the optical fiber coil at room temperature: opening the temperature box control software, setting the temperature measurement and constant temperature setting; Keep the temperature box at 25°C and open the fiber coil measurement software after the temperature stabilizes; Enter the coil number and generate a file directory, start measuring 10 minutes of normal temperature data, and calculate the optical fiber coil calibration factor K at normal temperature according to the formula: K = F / ω; Wherein, K is the calibration factor of the optical fiber coil at room temperature; F is the average value of the output data of the optical fiber coil at room temperature within 10 minutes, in LSB; ω is the celestial component of the local earth's rotation angular velocity; Step S14, rapid temperature change measurement: set the temperature of the incubator to 20°C and maintain it for 30 minutes to stabilize the temperature of the optical fiber coil; Set the temperature change process of the incubator, including constant temperature stages of 20℃, -5℃, 35℃ and 20℃, and a temperature change rate of 1℃ / min; Start the temperature change process and open the fiber coil measurement software for data acquisition. The test lasts for 135 minutes. After the test, stop the measurement and turn off the software and the temperature chamber power. Step S15, evaluate the test results: import data and calculate the Shupe coefficient, using the optical fiber coil performance evaluation software; set the basic parameters of the coil, including loop length, outer diameter and calibration factor; import the temperature setting file and measurement data, and the software automatically calculates the relevant parameters and Shupe coefficient; the smaller the Shupe coefficient, the better the performance of the optical fiber coil, and the Shupe coefficient is required to be ≤1; in the "coil curve modeling and compensation" interface of the software, import the 1s smoothed data of the rapid temperature change measurement, and calculate the nonlinear coefficient KNL, the formula is: K NL =S C / B S ; Where: K NL is the nonlinear coefficient, and the index system requires K NL ≤1.5; S C is the standard deviation after temperature compensation; B S is the zero bias stability of the coil at room temperature, calculated from the measurement data at room temperature.

3. According to claim 2, a method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment, characterized in that: The specific steps of adjusting the parameters of the optical fiber coil in step S12 include: The first step is to measure the special value frequency: Obtain the characteristic frequency reference value in the automatic parameter tuning module, and verify its accuracy in the manual parameter tuning module; Step 2: Coarse adjustment of half-wave voltage: Obtain the rough adjustment reference value of the half-wave voltage in the automatic parameter adjustment module, then make fine adjustments in the manual parameter adjustment module, and observe the PIN waveform effect to obtain the best value; Step 3: First bias adjustment: Obtain reference values ​​for positive and negative terminal adjustments in the automatic parameter adjustment module, and make fine adjustments in the manual parameter adjustment module to obtain a better PERR waveform; Step 4: Fine-tune the half-wave voltage: Obtain the half-wave voltage fine-tuning reference value in the automatic parameter adjustment module, and then make fine adjustments in the manual parameter adjustment module to obtain a better PERR waveform; Step 5: Modulation mode selection: Select the modulation type of the fiber optic gyroscope in the automatic parameter adjustment module; Step 6: Secondary bias adjustment: Fine-tune the positive and negative ends again to obtain a better PERR waveform, which supplements or verifies the third step; Step 7: Closed-loop test: After selecting the corresponding option, conduct a test and observe the fluctuations in SERR and PERR data; if there is no drastic fluctuation, save the data; if there is, perform a reverse operation and repeat the above steps.

4. According to claim 2, a method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment is characterized in that: The specific steps in step S13 include: The test data is saved in the form of "temperature chamber test data.txt" to a fixed path in the folder where this application is located. After each measurement, the file needs to be saved to another location to prevent it from being overwritten by data generated by subsequent tests.

5. According to claim 2, a method for testing an optical fiber coil based on a semiconductor constant temperature box and semi-automatic parameter adjustment, characterized in that: The specific steps in step S14 include: The data file used is derived from the 1s smoothed data file obtained in the previous step; If you obtain data files from other paths, you must ensure that the format of the file content is consistent with the content format of the corresponding file obtained from the software, otherwise the display analysis will not obtain correct results.

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