Temperature drift calibration method and system for MEMS three-dimensional deformation monitoring instrument

Abstract

The invention proposes a temperature drift calibration method and system for a MEMS three-dimensional deformation monitoring instrument. In a temperature-controlled test box, a plurality of test temperatures are set; the MEMS three-dimensional deformation monitoring instrument is used to obtain three-dimensional deformation sensing data of each rigid sensing segment under a test temperature change environment; least squares polynomial fitting is performed to obtain a fitting formula for temperature-three-dimensional deformation sensing data; a sensing data fitting value is obtained, and a temperature drift fitting coefficient is calculated according to the sensing data fitting value and a test temperature value; statistical calculation is performed on all three-dimensional deformation sensing data under the test temperature value, and the statistical calculation result is used as the sensing data actual value, and the temperature drift actual coefficient is calculated according to the sensing data actual value and the test temperature value; weighted calculation is performed on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain a temperature drift calibration value, and the temperature drift value generated by the sensor as the temperature changes is calibrated to avoid a large error value when performing data detection.

Description

Technical Field

[0001] The present invention relates to the technical field of sensor data correction, and in particular to a temperature drift calibration method and system for a MEMS three-dimensional deformation monitoring instrument. Background Art

[0002] The error of inertial devices is the main error source of inertial systems, and accelerometers are one of the core components of inertial systems. Accelerometers are usually composed of mass blocks, dampers, elastic elements, sensitive elements, and adaptive circuits. During the acceleration process, the inertial force on the mass block is measured, and the acceleration value is obtained using Newton's second law. Selecting a high-precision accelerometer can effectively improve the measurement accuracy of the inertial system.

[0003] However, due to temperature changes, the output voltage value of the acceleration sensor will also change with temperature changes. Therefore, the accuracy of its output acceleration value cannot be guaranteed, and there will be errors in practical applications. Summary of the invention

[0004] The object of the present invention is to solve at least one of the above-mentioned technical drawbacks.

[0005] To this end, an object of the present invention is to provide a temperature drift calibration method and system for a MEMS three-dimensional deformation monitoring instrument, so as to calibrate the temperature drift value of the sensor generated by temperature changes, so as to avoid large error values ​​when performing data detection.

[0006] In order to achieve the above object, an embodiment of one aspect of the present invention provides a method for calibrating a temperature drift of a MEMS three-dimensional deformation monitoring instrument, comprising the following steps:

[0007] S1. In a temperature-controlled test chamber, multiple test temperatures are set; a MEMS three-dimensional deformation monitor is used to obtain three-dimensional deformation sensing data of each rigid sensing segment under a test temperature change environment;

[0008] S2. Taking the set test temperature as the independent variable and the acquired three-dimensional deformation sensing data as the dependent variable, a least squares polynomial fitting is performed to obtain a fitting formula of temperature-three-dimensional deformation sensing data;

[0009] S3, taking any test temperature value as an independent variable, inputting it into the fitting formula of temperature-three-dimensional deformation sensing data, obtaining the sensing data fitting value, and calculating the temperature drift fitting coefficient according to the sensing data fitting value and the test temperature value;

[0010] S4, performing statistical calculation on all three-dimensional deformation sensing data under the test temperature value in S3, taking the statistical calculation result as the actual value of the sensing data, and calculating the actual temperature drift coefficient according to the actual value of the sensing data and the test temperature value;

[0011] S5. Perform weighted calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain the temperature drift calibration value.

[0012] Further preferably, the maximum value of the test temperature set in the temperature control test box is 70° and the minimum value is -40°.

[0013] Further preferably, the temperature control test box adjusts the test temperature as follows: first, the temperature is reduced from the current room temperature to -40°C, and maintained at -40°C for 1 hour, then the temperature is increased to 70°C, and the temperature is maintained at 70°C for 1 hour before cooling down. The experiment is completed when the temperature is reduced to room temperature.

[0014] Further preferably, the statistical calculation of all three-dimensional deformation sensing data under the test temperature value includes the following method: calculating the average value of the three-dimensional deformation sensing data of each rigid sensing segment under the test temperature value, and taking the average value as the actual value of the sensing data.

[0015] Further preferably, the statistical calculation of all three-dimensional deformation sensing data under the test temperature value includes the following method: obtaining the median of the three-dimensional deformation sensing data obtained by each rigid sensing segment under the test temperature value, and taking the median as the actual value of the sensing data.

[0016] Further preferably, in S5, the weighted calculation of the temperature drift fitting coefficient and the temperature drift actual coefficient comprises the following method:

[0017] Among them, W 标定 is the temperature drift calibration value, W 拟合 is the temperature drift fitting coefficient, W 实际 is the actual coefficient of temperature drift.

[0018] The present invention also provides a temperature drift calibration system for a MEMS three-dimensional deformation monitor, comprising a temperature control test box, a MEMS three-dimensional deformation monitor, a collection device and a host computer;

[0019] The temperature control test box is used to set multiple test temperatures, including setting the maximum and minimum values ​​of the test temperatures;

[0020] The MEMS three-dimensional deformation monitor includes a built-in MEMS three-dimensional deformation sensor;

[0021] The acquisition device is connected to each MEMS three-dimensional deformation sensor to obtain the three-dimensional deformation sensing data of each rigid sensing segment under the test temperature change environment;

[0022] The host computer uses the set test temperature as an independent variable and the acquired three-dimensional deformation sensing data as a dependent variable to perform least squares polynomial fitting to obtain a fitting formula for temperature-three-dimensional deformation sensing data; uses any test temperature value as an independent variable, inputs it into the fitting formula for temperature-three-dimensional deformation sensing data, obtains a fitting value of the sensing data, and calculates a temperature drift fitting coefficient according to the fitting value of the sensing data and the test temperature value; performs statistical calculations on all three-dimensional deformation sensing data under the test temperature value, uses the statistical calculation results as the actual value of the sensing data, and calculates the actual temperature drift coefficient according to the actual value of the sensing data and the test temperature value; and performs weighted calculations on the temperature drift fitting coefficient and the actual temperature drift coefficient to obtain a temperature drift calibration value.

[0023] Further preferably, the MEMS three-dimensional deformation monitor comprises a plurality of groups of connected rigid sensing segments and flexible joints, each group of the rigid sensing segments is connected to another group of flexible joints, and the rigid sensing segments have built-in MEMS three-dimensional deformation sensors.

[0024] Further preferably, the length of the rigid sensing segment varies from 0.5 m, 1 m, to 1.5 m, and the maximum value of the set test temperature of the temperature-controlled test box is 70°, and the minimum value is -40°.

[0025] The temperature drift calibration method and system of the MEMS three-dimensional deformation monitoring instrument provided according to the embodiments of the present invention have at least the following advantages compared with the prior art:

[0026] 1. The temperature drift calibration method and system of the MEMS three-dimensional deformation monitoring instrument provided by the embodiment of the present invention adjusts the test temperature, takes the acquired three-dimensional deformation sensing data as the dependent variable, performs least squares polynomial fitting, and uses the fitted data and the real data for weighted calculation to obtain the final temperature drift calibration value, 0

[0027] 2. A method and system for calibrating a temperature drift of a MEMS three-dimensional deformation monitor provided by an embodiment of the present invention.

[0028] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0030] Figure 1 This is a flow chart of the temperature drift calibration method of the MEMS three-dimensional deformation monitoring instrument of the present invention; DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0032] like Figure 1 As shown, a temperature drift calibration method of a MEMS three-dimensional deformation monitoring instrument according to an embodiment of the present invention comprises the following steps:

[0033] S1. In a temperature-controlled test chamber, multiple test temperatures are set; a MEMS three-dimensional deformation monitor is used to obtain three-dimensional deformation sensing data of each rigid sensing segment under a test temperature change environment;

[0034] S2. Taking the set test temperature as the independent variable and the acquired three-dimensional deformation sensing data as the dependent variable, a least squares polynomial fitting is performed to obtain a fitting formula of temperature-three-dimensional deformation sensing data;

[0035] S3, taking any test temperature value as an independent variable, inputting it into the fitting formula of temperature-three-dimensional deformation sensing data, obtaining the sensing data fitting value, and calculating the temperature drift fitting coefficient according to the sensing data fitting value and the test temperature value;

[0036] S4, performing statistical calculation on all three-dimensional deformation sensing data under the test temperature value in S3, taking the statistical calculation result as the actual value of the sensing data, and calculating the actual temperature drift coefficient according to the actual value of the sensing data and the test temperature value;

[0037] S5. Perform weighted calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain the temperature drift calibration value.

[0038] Further preferably, the maximum value of the test temperature set in the temperature control test box is 70° and the minimum value is -40°.

[0039] Further preferably, the temperature control test box adjusts the test temperature as follows: first, the temperature is reduced from the current room temperature to -40°C, and maintained at -40°C for 1 hour, then the temperature is increased to 70°C, and the temperature is maintained at 70°C for 1 hour before cooling down. The experiment is completed when the temperature is reduced to room temperature.

[0040] Further preferably, the statistical calculation of all three-dimensional deformation sensing data under the test temperature value includes the following method: calculating the average value of the three-dimensional deformation sensing data of each rigid sensing segment under the test temperature value, and taking the average value as the actual value of the sensing data.

[0041] Further preferably, the statistical calculation of all three-dimensional deformation sensing data under the test temperature value includes the following method: obtaining the median of the three-dimensional deformation sensing data obtained by each rigid sensing segment under the test temperature value, and taking the median as the actual value of the sensing data.

[0042] Further preferably, in S5, the weighted calculation of the temperature drift fitting coefficient and the temperature drift actual coefficient includes:

[0043]

[0044] Among them, W 标定 is the temperature drift calibration value, W 拟合 is the temperature drift fitting coefficient, W 实际 is the actual coefficient of temperature drift.

[0045] Use the following formula to calculate the fitted temperature drift coefficient or actual temperature drift coefficient of the sensor.

[0046]

[0047] In the formula, y 0 (T 1 ) is the zero-point output value of the sensor at room temperature T1; 0 (T 2 ) is the zero output value of the sensor after being kept at a specified high or low temperature T2 for a specified time; Y fs (T 1 ) is the theoretical full-scale output of the sensor at temperature T1.

[0048] The present invention also provides a temperature drift calibration system for a MEMS three-dimensional deformation monitor, comprising a temperature control test box, a MEMS three-dimensional deformation monitor, a collection device and a host computer;

[0049] The temperature control test box is used to set multiple test temperatures, including setting the maximum and minimum values ​​of the test temperatures;

[0050] The MEMS three-dimensional deformation monitor includes a built-in MEMS three-dimensional deformation sensor;

[0051] The acquisition device is connected to each MEMS three-dimensional deformation sensor to obtain the three-dimensional deformation sensing data of each rigid sensing segment under the test temperature change environment;

[0052] The host computer uses the set test temperature as an independent variable and the acquired three-dimensional deformation sensing data as a dependent variable to perform least squares polynomial fitting to obtain a fitting formula for temperature-three-dimensional deformation sensing data; uses any test temperature value as an independent variable, inputs it into the fitting formula for temperature-three-dimensional deformation sensing data, obtains a fitting value of the sensing data, and calculates a temperature drift fitting coefficient according to the fitting value of the sensing data and the test temperature value; performs statistical calculations on all three-dimensional deformation sensing data under the test temperature value, uses the statistical calculation results as the actual value of the sensing data, and calculates the actual temperature drift coefficient according to the actual value of the sensing data and the test temperature value; and performs weighted calculations on the temperature drift fitting coefficient and the actual temperature drift coefficient to obtain a temperature drift calibration value.

[0053] Further preferably, the MEMS three-dimensional deformation monitor comprises a plurality of groups of connected rigid sensing segments and flexible joints, each group of the rigid sensing segments is connected to another group of flexible joints, and the rigid sensing segments have built-in MEMS three-dimensional deformation sensors.

[0054] Preferably, the length of the rigid sensing segment is 0.5 m, 1 m, or 1.5 m, and the maximum value of the set test temperature of the temperature control test box is 70° and the minimum value is -40°.

[0055] In one embodiment of the present invention, first, a MEMS three-dimensional deformation monitor is connected in the order of a rigid sensing segment, a flexible joint, a rigid sensing segment, and a flexible joint, and the connected MEMS three-dimensional deformation monitor is placed in a temperature-controlled experimental box. (2) The temperature parameters of the temperature-controlled experimental box are set, and the temperature parameter setting range is -40° to 70°. (3) The MEMS three-dimensional deformation monitor inside the experimental box is connected to a collection device, and the collection device collects data from the MEMS three-dimensional deformation monitor inside the experimental box. (4) The data is solved, and the data of the MEMS three-dimensional deformation monitor is processed by the least squares polynomial fitting formula to obtain a formula for correcting temperature drift. After the temperature of the temperature-controlled experimental box is set, the specific experimental process is to first reduce the temperature from the current room temperature to -40°, maintain it at -40° for 1 hour, then increase the temperature to 70°, maintain it at 70° for 1 hour, and then start to cool down. The experiment is completed after the temperature drops to room temperature.

[0056] Taking the set test temperature as the independent variable and the acquired three-dimensional deformation sensing data as the dependent variable, the least squares polynomial fitting is performed to obtain the fitting formula of temperature-three-dimensional deformation sensing data. According to the given m points, it is not required that the curve passes through these points exactly, but the approximate curve y=φ(x) of the curve y=f(x). Generally, increasing the order of the fitting polynomial does not improve the fitting accuracy, and the collected data curve is also an arc, so the polynomial fitting order of the second order can be used. The calculation formula of the second order is as follows:

[0057] y=a 0 +a 1 x+a 2 x 2

[0058] The quadratic fitting of the least squares method was used to obtain the fitting formula of the temperature-three-dimensional deformation sensing data.

[0059] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0060] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A temperature drift calibration method for MEMS three-dimensional deformation monitoring instrument, It is characterized in that The following steps are involved: S1. In a temperature-controlled test chamber, multiple test temperatures are set; a MEMS three-dimensional deformation monitor is used to obtain three-dimensional deformation sensing data of each rigid sensing segment under a test temperature change environment; S2. Taking the set test temperature as the independent variable and the acquired three-dimensional deformation sensing data as the dependent variable, a least squares polynomial fitting is performed to obtain a fitting formula of temperature-three-dimensional deformation sensing data; S3, taking any test temperature value as an independent variable, inputting it into the fitting formula of temperature-three-dimensional deformation sensing data, obtaining the sensing data fitting value, and calculating the temperature drift fitting coefficient according to the sensing data fitting value and the test temperature value; S4, performing statistical calculation on all three-dimensional deformation sensing data under the test temperature value in S3, taking the statistical calculation result as the actual value of the sensing data, and calculating the actual temperature drift coefficient according to the actual value of the sensing data and the test temperature value; S5. Perform weighted calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain a temperature drift calibration value; the weighted calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient includes the following method: Among them, W 标定 is the temperature drift calibration value, W 拟合 is the temperature drift fitting coefficient, W 实际 is the actual coefficient of temperature drift.

2. The temperature drift calibration method of the MEMS three-dimensional deformation monitoring instrument according to claim 1, It is characterized in that The maximum test temperature of the temperature control test box is set to 70° and the minimum test temperature is set to -40°.

3. The temperature drift calibration method of the MEMS three-dimensional deformation monitoring instrument according to claim 2, It is characterized in that The temperature control test box adjusts the test temperature according to the following method: First, the temperature is lowered from the current room temperature to -40°C and maintained at -40°C for 1 hour. Then the temperature is raised to 70°C and maintained at 70°C for 1 hour before cooling down. The experiment is completed when the temperature drops to room temperature.

4. The temperature drift calibration method of the MEMS three-dimensional deformation monitoring instrument according to claim 1, It is characterized in that Statistical calculations are performed on all three-dimensional deformation sensing data at the test temperature values, including the following methods: The average value of the three-dimensional deformation sensing data of each rigid sensing segment under the test temperature value is calculated, and the average value is used as the actual value of the sensing data.

5. The temperature drift calibration method of the MEMS three-dimensional deformation monitoring instrument according to claim 1, It is characterized in that Statistical calculations are performed on all three-dimensional deformation sensing data at the test temperature values, including the following methods: The median of the three-dimensional deformation sensing data obtained by each rigid sensing segment under the test temperature value is calculated and used as the actual value of the sensing data.

6. A temperature drift calibration system for a MEMS three-dimensional deformation monitor, used to implement the steps of the temperature drift calibration method for a MEMS three-dimensional deformation monitor as described in any one of claims 1 to 5. It is characterized in that Including temperature control test chamber, MEMS three-dimensional deformation monitor, acquisition equipment and host computer; The temperature control test box is used to set multiple test temperatures, including setting the maximum and minimum values ​​of the test temperatures; The MEMS three-dimensional deformation monitor includes a built-in MEMS three-dimensional deformation sensor; The acquisition device is connected to each MEMS three-dimensional deformation sensor to obtain the three-dimensional deformation sensing data of each rigid sensing segment under the test temperature change environment; The host computer uses the set test temperature as an independent variable and the acquired three-dimensional deformation sensing data as a dependent variable to perform least squares polynomial fitting to obtain a fitting formula for temperature-three-dimensional deformation sensing data; any test temperature value is used as an independent variable, input into the fitting formula for temperature-three-dimensional deformation sensing data, obtains a fitting value of the sensing data, and calculates a temperature drift fitting coefficient according to the fitting value of the sensing data and the test temperature value; Performing statistical calculations on all three-dimensional deformation sensing data under the test temperature value, taking the statistical calculation results as the actual values ​​of the sensing data, and calculating the actual coefficient of temperature drift according to the actual values ​​of the sensing data and the test temperature value; The temperature drift fitting coefficient and the temperature drift actual coefficient are weightedly calculated to obtain the temperature drift calibration value.

7. The temperature drift calibration system of the MEMS three-dimensional deformation monitoring instrument according to claim 6, It is characterized in that The MEMS three-dimensional deformation monitor comprises a plurality of groups of connected rigid sensing segments and flexible joints, each group of the rigid sensing segments is connected to another group of flexible joints, and the rigid sensing segments have built-in MEMS three-dimensional deformation sensors.

8. The temperature drift calibration system of the MEMS three-dimensional deformation monitoring instrument according to claim 7, It is characterized in that The lengths of the rigid sensing segments vary from 0.5 m, 1 m, to 1.5 m. The maximum value of the set test temperature of the temperature-controlled test box is 70°, and the minimum value is -40°.

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