Fusion calibration method, system and equipment of fiber grating sensor data and medium

Abstract

The invention relates to the technical field of fiber bragg grating sensor calibration, in particular to a fiber bragg grating sensor data fusion calibration method, system, device and medium, and the method comprises the following steps: initializing a calibration table, and generating calibration point physical quantities by setting the number of calibration points and the order of a fitting function; acquiring single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator by using a multi-protocol parallel communication framework until wavelength data under all temperature points and strain points are acquired, and fitting the wavelength data under all temperature / strain points with corresponding physical quantities to obtain the wavelength data under all temperature / strain points; and obtaining a wavelength temperature fitting coefficient and a wavelength strain fitting coefficient, and obtaining a calibration result of the fiber grating sensor based on the wavelength temperature fitting coefficient and the wavelength strain fitting coefficient. According to the method, manual operation links can be reduced, the method is suitable for adapting to a batch sensor calibration scene, and the overall consumed time is remarkably shortened due to the fact that upper computer software does not need to be repeatedly developed for different demodulators.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fiber grating sensor calibration, in particular to a fusion calibration method, system, device and medium for fiber grating sensor data. BACKGROUND

[0002] The fiber grating sensor belongs to a kind of fiber sensor, and the sensing process based on fiber grating is to obtain sensing information by the modulation of physical parameters on fiber Bragg wavelength, which is a wavelength modulation type fiber sensor. Before the fiber grating sensor is put into practical use, it needs to be calibrated for temperature, strain and other physical quantities, and the corresponding relationship between wavelength and physical quantity is established to provide key guarantee for the accuracy of subsequent measurement data.

[0003] The current calibration of fiber grating sensor mainly uses single-channel spectrometer to record manually, which has the following defects: (1) low calibration efficiency: since the temperature and strain physical quantities need to be loaded manually one by one, for batch sensor calibration scene, the overall time consumption is too long; (2) poor compatibility: different manufacturers' fiber grating demodulator communication protocols and data formats are different, so when facing single-channel / multi-channel data acquisition requirements of multiple types of demodulators, the host computer software needs to be developed repeatedly, further reducing the calibration efficiency.

[0004] Therefore, it is a technical problem to be solved at present to research a high-efficiency and high-compatibility fiber grating sensor calibration method. SUMMARY

[0005] The present application aims to provide a fusion calibration method, system, device and medium for fiber grating sensor data to solve the technical problems pointed out in the background.

[0006] The present application is implemented by the following technical scheme: a fusion calibration method for fiber grating sensor data, comprising the following steps: Initialize the calibration table, generate calibration point physical quantities by setting the number of calibration points and the order of fitting function, load the calibration point physical quantities to the fiber grating sensor, and the physical quantities include temperature and strain; Obtain single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator using a multi-protocol parallel communication framework until all wavelength data under temperature points and strain points are collected; Fit the temperature physical quantity and all wavelength data under temperature points to obtain wavelength temperature fitting coefficients, and fit the strain physical quantity and all wavelength data under strain points to obtain wavelength strain fitting coefficients; Based on the wavelength temperature fitting coefficients and wavelength strain fitting coefficients, the calibration result of the fiber grating sensor is obtained.

[0007] According to a preferred embodiment, the single-channel wavelength data is obtained from the fiber grating demodulator through a Modbus protocol, and the multi-channel wavelength data is obtained from the fiber grating demodulator through a private binary protocol.

[0008] According to a preferred embodiment, during the wavelength data acquisition process, the temperature physical quantity or the strain physical quantity is loaded to the fiber grating sensor in the positive and negative directions of the physical quantity change, and the wavelength data corresponding to the positive and negative directions of the physical quantity change is averaged.

[0009] According to a preferred embodiment, during the process of obtaining the single-channel wavelength data or the multi-channel wavelength data from the fiber grating demodulator, a data request is sent to the fiber grating demodulator based on a timeout retransmission mechanism.

[0010] According to a preferred embodiment, the fitting of the wavelength data adopts polynomial fitting.

[0011] According to a preferred embodiment, the method further comprises storing the calibration result in CSV format.

[0012] The present application also provides a fusion calibration system for fiber grating sensor data, which is applied to the fusion calibration method for fiber grating sensor data as described above, and the system comprises an upper computer calibration unit, a fiber grating demodulator, a temperature loading unit and a strain loading unit. The upper computer calibration unit is composed of a loading module, a thread scheduling module and a data processing module. The loading module is used to initialize a calibration table, generate calibration point physical quantities by setting the number of calibration points and the order of fitting functions, and load the calibration point physical quantities to the fiber grating sensor, wherein the physical quantities include temperature and strain. The thread scheduling module is used to obtain single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator through a multi-protocol parallel communication framework until the wavelength data under all temperature points and strain points are acquired. The data processing module is used to fit the temperature physical quantity and the wavelength data under all temperature points to obtain wavelength temperature fitting coefficients, fit the strain physical quantity and the wavelength data under all strain points to obtain wavelength strain fitting coefficients, and obtain the calibration result of the fiber grating sensor based on the wavelength temperature fitting coefficients and the wavelength strain fitting coefficients.

[0013] According to a preferred embodiment, the multi-protocol parallel communication framework comprises at least two path branches, one path branch is connected to the fiber grating demodulator through the Modbus protocol to read single-channel wavelength data from the fiber grating demodulator, and the other path is connected to the fiber grating demodulator through a private binary protocol to read batch multi-channel wavelength data from the fiber grating demodulator.

[0014] The application further provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the fusion calibration method of fiber grating sensor data when executing the computer program.

[0015] The application further provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executable on a processor to implement the fusion calibration method of fiber grating sensor data.

[0016] The fusion calibration method of fiber grating sensor data provided by the application has at least the following advantages and beneficial effects: manual point-by-point recording of temperature and strain parameters is not required, the number of calibration points and the order of the fitting function are set to automatically generate calibration point physical quantities and load them, which can reduce manual operation links; single / multi-channel wavelength data are synchronously collected by using a multi-protocol parallel communication framework, which is particularly suitable for batch sensor calibration scenarios, and the overall time consumption can be significantly shortened because there is no need to repeatedly develop host computer software for different demodulators. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A fusion calibration method flowchart is provided for the embodiment 1 of the application; Figure 2 A host computer calibration unit structure block diagram is provided for the embodiment 5 of the application. DETAILED DESCRIPTION

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the application clearer, the technical solutions in the embodiments of the application will be described below in conjunction with the drawings of the embodiments of the application. Obviously, the described embodiments are some but not all of the embodiments of the application. The components of the embodiments of the application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0019] Embodiment 1 The embodiments of the application provide a fusion calibration method of fiber grating sensor data, Figure 1 A fusion calibration method flowchart is provided for the embodiment 1 of the application; Figure 1 As shown in the figure, the fusion calibration method comprises the following steps: Step S1, initializing the calibration table; The wavelength change of the fiber grating sensor is affected by strain and temperature. In some embodiments, the calibration table is stored in Excel format, the temperature physical quantity includes 5-10 temperature points, such as -40℃, 0℃, 25℃, 50℃, and 85℃, which can be customized according to the use scene of the sensor, and the strain physical quantity includes 5-8 strain points, such as 0με, 500με, 1000με, 1500με, and 2000με, which are not specifically limited here.

[0020] Step S2, loading the calibration physical quantity; In this embodiment, the calibration point physical quantity is automatically generated by setting the number of calibration points and the order of the fitting function, and the calibration point physical quantity is loaded to the fiber grating sensor to change the temperature or strain parameter of the fiber grating sensor to simulate the actual use scene.

[0021] In some embodiments, the temperature loading is realized by a high-precision temperature control box, which communicates with the host computer calibration unit through the RS485 interface; the strain loading is realized by an electronic universal testing machine, which is manually adjusted to the preset amount.

[0022] Step S3, wavelength data acquisition; Single-channel wavelength data or multi-channel wavelength data is obtained from the fiber grating demodulator by using a multi-protocol parallel communication framework, and wavelength data under all temperature points and strain points are collected until the temperature calibration table and the strain calibration table are perfected.

[0023] Step S4, temperature calibration calculation and strain calibration calculation; The wavelength data under all temperature points and the temperature physical quantity are fitted to obtain the wavelength temperature fitting coefficient; the wavelength data under all strain points and the strain physical quantity are fitted to obtain the wavelength strain fitting coefficient.

[0024] In some embodiments, the wavelength data under all temperature points and the temperature physical quantity are fitted by using polynomial fitting, which can be expressed as: wherein is the wavelength, is the temperature, , , and represents the wavelength temperature fitting coefficient, and the wavelength strain fitting coefficient is the same, which is not described in detail here.

[0025] It should be noted that, in addition to polynomial fitting, one of cubic spline interpolation or neural network regression can also be used, which is not described in detail here.

[0026] Step S5, calibration result output; Based on the wavelength temperature fitting coefficient and the wavelength strain fitting coefficient, a calibration result of the fiber grating sensor is obtained; in some embodiments of the embodiment, the calibration result is stored and output in CSV format.

[0027] In summary, the fusion calibration method provided in the embodiment does not require manual point-by-point recording of temperature and strain parameters, and automatically generates calibration point physical quantities and loads them by setting the number of calibration points and the order of the fitting function, which can reduce manual operation links; the multi-protocol parallel communication framework is used to synchronously collect single / multi-channel wavelength data, which is especially suitable for batch sensor calibration scenarios, and because there is no need to repeatedly develop host computer software for different demodulators, the overall time consumption can be significantly reduced.

[0028] Embodiment 2 Based on the technical solutions provided in Embodiment 1, the acquisition of single-channel wavelength data and multi-channel wavelength data is further described: In the embodiment, the single-channel wavelength data is acquired from the fiber grating demodulator through the Modbus protocol; in some embodiments, the host computer sends a "read wavelength data" instruction through the Modbus protocol, and the fiber grating demodulator returns 2 bytes of wavelength data, which is converted and stored by the host computer; it should be noted that the Modbus protocol is suitable for single fiber grating sensor calibration or small batch calibration, and the protocol is highly versatile and does not need to be adapted to different manufacturer equipment.

[0029] The multi-channel wavelength data is acquired from the fiber grating demodulator through a private binary protocol; in some embodiments, the host computer sends a batch reading instruction through the UDP protocol, and the fiber grating demodulator returns multi-channel wavelength data through a ring buffer to prevent memory overflow; it should be noted that this protocol is suitable for large batch fiber grating sensor calibration and can reduce the overall calibration time, wherein the private protocol requires the manufacturer to provide a frame structure document, and the host computer calibration unit supports protocol parameter self-defined configuration, thereby adapting different manufacturer multi-channel demodulators. In addition, for the acquisition of multi-channel wavelength data, a 9000 port service can also be used to simultaneously acquire real-time wavelength data of multiple channels and multiple fiber grating sensors, which will not be described in detail here.

[0030] Embodiment 3 Based on the technical solutions provided in Embodiment 1, the loading process of the physical quantity is further described: In the embodiment, in the wavelength data acquisition process, the temperature physical quantity or the strain physical quantity in the preset calibration table is loaded to the fiber grating sensor from the positive direction of the physical quantity change and the negative direction of the physical quantity change respectively; for the wavelength data acquisition under the temperature physical quantity loading, one round of wavelength data of all temperature points is collected from the positive direction from low temperature to high temperature and the negative direction from high temperature to low temperature respectively; for the wavelength data acquisition under the strain physical quantity loading, one round of wavelength data of all strain points is collected from the positive direction from no strain to maximum strain and the negative direction from maximum strain to no strain respectively.

[0031] The wavelength data corresponding to the positive direction and the negative direction of the physical quantity change is averaged; in the embodiment, the positive direction wavelength data and the negative direction wavelength data of the same temperature / strain point are arithmetically averaged, so that the wavelength data acquisition deviation can be significantly reduced.

[0032] Embodiment 4 The embodiment is based on the technical solution provided in the embodiment 1, and further illustrates the acquisition of the wavelength data: In the embodiment, in the process of acquiring single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator, a data request is sent to the fiber grating demodulator based on a timeout retransmission mechanism.

[0033] The timeout retransmission mechanism is as follows: each wavelength data request attempts to send multiple times in a loop, waits for a response after each sending, retries if it times out, and returns a timeout error if all retries fail.

[0034] Embodiment 5 The embodiment is based on the technical solution provided in any one of the embodiments 1 to 4, and provides a fusion calibration system for fiber grating sensor data, which is applied to the fusion calibration method for fiber grating sensor data provided in any one of the embodiments 1 to 4; In the embodiment, the system comprises an upper computer calibration unit, a fiber grating demodulator, a temperature loading unit and a strain loading unit. Referring to Figure 2 The upper computer calibration unit is composed of a loading module, a thread scheduling module and a data processing module. The loading module is used to initialize a calibration table, generate calibration point physical quantities by setting the number of calibration points and the order of fitting functions, load the calibration point physical quantities to the fiber grating sensor, and the physical quantities include temperature and strain. The thread scheduling module is used to acquire single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator by using a multi-protocol parallel communication framework until the wavelength data under all temperature points and strain points are collected. The data processing module is configured to fit the temperature physical quantity and wavelength data at all temperature points to obtain a wavelength-temperature fitting coefficient, fit the strain physical quantity and wavelength data at all strain points to obtain a wavelength-strain fitting coefficient, and obtain a calibration result of the fiber grating sensor based on the wavelength-temperature fitting coefficient and the wavelength-strain fitting coefficient.

[0035] In some embodiments of the present embodiment, the multi-protocol parallel communication framework includes at least two path branches, one path branch is connected to the fiber grating demodulator through the Modbus protocol to read single-channel wavelength data from the fiber grating demodulator, and the other path is connected to the fiber grating demodulator through a private binary protocol to read batch multi-channel wavelength data from the fiber grating demodulator.

[0036] Embodiment 6 The present embodiment provides an electronic device based on the technical solutions provided in any one of embodiments 1 to 4, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the fusion calibration method of the fiber grating sensor data when executing the computer program.

[0037] Embodiment 7 The present embodiment provides a computer readable storage medium based on the technical solutions provided in any one of embodiments 1 to 4, which stores a computer program, and the computer program is executable on a processor to implement the fusion calibration method of the fiber grating sensor data as described in any one of embodiments 1 to 4.

[0038] The above is only the preferred embodiment of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A fusion calibration method for fiber grating sensor data, characterized in that, The method comprises the following steps: initializing a calibration table, generating calibration point physical quantities by setting the number of calibration points and the order of fitting functions, loading the physical quantities to the fiber grating sensor, the physical quantities including temperature and strain; acquiring single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator using a multi-protocol parallel communication framework until wavelength data at all temperature points and strain points are collected; fitting the temperature physical quantities and the wavelength data at all temperature points to obtain wavelength temperature fitting coefficients, and fitting the strain physical quantities and the wavelength data at all strain points to obtain wavelength strain fitting coefficients; obtaining the calibration result of the fiber grating sensor based on the wavelength temperature fitting coefficients and the wavelength strain fitting coefficients.

2. The fusion calibration method of fiber grating sensor data according to claim 1, wherein, The single-channel wavelength data is acquired from the fiber grating demodulator through the Modbus protocol, and the multi-channel wavelength data is acquired from the fiber grating demodulator through a private binary protocol.

3. The fusion calibration method of fiber grating sensor data according to claim 1, wherein, During the wavelength data collection process, the temperature physical quantities or the strain physical quantities are loaded to the fiber grating sensor from the positive and negative directions of the physical quantity change, and the wavelength data corresponding to the positive and negative directions of the physical quantity change are averaged. 4.The fusion calibration method of fiber grating sensor data according to claim 1, wherein, During the acquisition of single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator, a data request is sent to the fiber grating demodulator based on a timeout retransmission mechanism. 5.The fusion calibration method of fiber grating sensor data according to claim 1, wherein, The fitting of the wavelength data adopts polynomial fitting. 6.The fusion calibration method of fiber grating sensor data according to claim 1, wherein, The method further comprises storing the calibration result in CSV format.

7. A fusion calibration system for fiber grating sensor data, characterized by, The system comprises an upper computer calibration unit, a fiber grating demodulator, a temperature loading unit, and a strain loading unit. The upper computer calibration unit comprises a loading module, a thread scheduling module, and a data processing module. The loading module is used to initialize a calibration table, generate calibration point physical quantities by setting the number of calibration points and the order of fitting functions, and load the calibration point physical quantities to the fiber grating sensor, the physical quantities including temperature and strain. The thread scheduling module is used to acquire single-channel wavelength data or multi-channel wavelength data from the fiber grating demodulator using a multi-protocol parallel communication framework until wavelength data at all temperature points and strain points are collected. The data processing module is used to fit the temperature physical quantities and the wavelength data at all temperature points to obtain wavelength temperature fitting coefficients, and fit the strain physical quantities and the wavelength data at all strain points to obtain wavelength strain fitting coefficients, and obtain the calibration result of the fiber grating sensor based on the wavelength temperature fitting coefficients and the wavelength strain fitting coefficients.

8. The fusion calibration system of fiber grating sensor data according to claim 7, wherein, The multi-protocol parallel communication framework comprises at least two path branches, one path branch is connected to the fiber grating demodulator through the Modbus protocol to read single-channel wavelength data from the fiber grating demodulator, and the other path is connected to the fiber grating demodulator through a private binary protocol to batch read multi-channel wavelength data from the fiber grating demodulator.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor implements the fiber grating sensor data fusion calibration method of any one of claims 1-6 when executing the computer program.

10. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by the processor to implement the fusion calibration method of the fiber grating sensor data according to any one of claims 1 to 6.

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