CN115046524A - Temperature drift calibration method and system for MEMS three-dimensional deformation monitor - Google Patents

Abstract

The invention provides a temperature drift calibration method and a temperature drift calibration system for an MEMS three-dimensional deformation monitor, wherein a plurality of test temperatures are set in a temperature control test box; acquiring three-dimensional deformation sensing data of each rigid sensing section in an environment with test temperature change by using an MEMS three-dimensional deformation monitor; performing least square polynomial fitting to obtain a fitting formula of the temperature-three-dimensional deformation induction data; obtaining a fitting value of induction data, and calculating a temperature drift fitting coefficient according to the fitting value of the induction data and a test temperature value; performing statistical calculation on all three-dimensional deformation sensing data at a test temperature value, taking a statistical calculation result as an actual value of the sensing data, and calculating an actual temperature drift coefficient according to the actual value of the sensing data and the test temperature value; and performing weighting calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain a temperature drift calibration value, and calibrating the temperature drift value generated along with the temperature change of the sensor, so as to avoid a large error value during data detection.

Description

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

technical field

The invention relates to the technical field of sensor data correction, in particular to a temperature drift calibration method and system of a MEMS three-dimensional deformation monitor.

Background technique

The error of the inertial device is the main error source of the inertial system, and the accelerometer is one of the core components of the inertial system. 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 by using Newton's second law. Selecting a high-precision accelerometer can effectively improve the measurement accuracy of the inertial system.

However, due to the temperature change, the output voltage value of the acceleration sensor will also change with the temperature change, so the accuracy of the output acceleration value cannot be guaranteed, and there will be errors in practical applications.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve at least one of the aforementioned technical defects.

Therefore, an object of the present invention is to propose a method and system for calibrating the temperature drift of a MEMS three-dimensional deformation monitor, which can calibrate the temperature drift value of the sensor with the temperature change, so as to avoid the occurrence of large error values during data detection. .

In order to achieve the above purpose, an embodiment of the present invention provides a method for calibrating temperature drift of a MEMS three-dimensional deformation monitor, comprising the following steps:

S1. In the temperature control test box, set multiple test temperatures; use the MEMS three-dimensional deformation monitor to obtain the three-dimensional deformation sensing data of each rigid sensing segment in the environment where the test temperature changes;

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

S3, take any test temperature value as an independent variable, input the fitting formula of temperature-three-dimensional deformation sensing data, obtain the fitting value of the sensing data, and calculate the temperature drift fitting according to the fitting value of the sensing data and the test temperature value coefficient;

S4, performing statistical calculation on all three-dimensional deformation sensing data under the test temperature value in S3, using the statistical calculation result as the actual value of the sensing data, and calculating the actual coefficient of temperature drift 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 the temperature drift calibration value.

Further preferably, the maximum value of the set test temperature set by the temperature test box is 70°, and the minimum value is -40°.

Further preferably, the temperature test chamber adjusts the test temperature according to the following method: firstly, it is lowered from the current room temperature to -40°C, kept at -40°C for 1 hour, then heated to 70°C, and then heated to 70°C under the temperature condition of 70°C. After holding for 1 hour, the temperature began to drop, and the temperature dropped to room temperature to complete the experiment.

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 calculating the The average value is taken as the actual value of the sensing data.

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. , take the median as the actual value of the sensing data.

Further preferably, in S5, the weighted calculation of the temperature drift fitting coefficient and the temperature drift actual coefficient includes the following methods:

Among them, W is the _calibration value of temperature drift, W is the _fitting coefficient of temperature drift, and W is the _actual coefficient of temperature drift.

The invention also provides a temperature drift calibration system of 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;

The temperature-controlled test box is used to set a plurality of 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, and is used to obtain the three-dimensional deformation sensing data of each rigid sensing segment under the environment of testing temperature change;

The host computer takes the set test temperature as the independent variable, and the acquired three-dimensional deformation sensing data as the dependent variable, performs least squares polynomial fitting, and obtains the fitting formula of temperature-three-dimensional deformation sensing data; value as an independent variable, input the fitting formula of temperature-three-dimensional deformation induction data, obtain the fitting value of the induction data, and calculate the temperature drift fitting coefficient according to the fitting value of the induction data and the test temperature value; , perform statistical calculation on all three-dimensional deformation sensing data, take the statistical calculation result as the actual value of the sensing data, and calculate the actual coefficient of temperature drift according to the actual value of the sensing data and the test temperature value; Carry out weighted calculation to obtain the calibration value of temperature drift.

Further preferably, the MEMS three-dimensional deformation monitor includes multiple sets of connected rigid sensing segments and flexible joints, each group of the rigid sensing segments is connected to another set of flexible joints, and the rigid sensing segments are Built-in MEMS three-dimensional deformation sensor.

Further preferably, the length of the rigid sensing segment is 0.5m, 1m, 1.5m, and the maximum value of the set test temperature set by the temperature test chamber is 70°, and the minimum value is -40°.

Compared with the prior art, the method and system for calibrating the temperature drift of a MEMS three-dimensional deformation monitor provided according to the embodiments of the present invention have at least the following advantages:

1. The method and system for calibrating the temperature drift of a MEMS three-dimensional deformation monitor provided by the embodiment of the present invention, by adjusting the test temperature, and taking the acquired three-dimensional deformation sensing data as the dependent variable, the least squares polynomial fitting is performed, and the result obtained by the fitting is used. The data and the real data are weighted and calculated, the final temperature drift calibration value, 0

2. The method and system for calibrating the temperature drift of a MEMS three-dimensional deformation monitor provided by the embodiment of the present invention,

Additional aspects and advantages of the present invention will be set forth, in part, from the following description, and in part will be apparent from the following description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of embodiments taken in conjunction with the accompanying drawings, wherein:

Fig. 1 is the flow chart of the temperature drift calibration method of MEMS three-dimensional deformation monitor of the present invention;

Detailed ways

The following describes in detail the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

As shown in FIG. 1 , a method for calibrating temperature drift of a MEMS three-dimensional deformation monitor according to an embodiment of the present invention includes the following steps:

S1. In the temperature control test box, set multiple test temperatures; use the MEMS three-dimensional deformation monitor to obtain the three-dimensional deformation sensing data of each rigid sensing segment in the environment where the test temperature changes;

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

S3, take any test temperature value as an independent variable, input the fitting formula of temperature-three-dimensional deformation sensing data, obtain the fitting value of the sensing data, and calculate the temperature drift fitting according to the fitting value of the sensing data and the test temperature value coefficient;

S4, performing statistical calculation on all three-dimensional deformation sensing data under the test temperature value in S3, using the statistical calculation result as the actual value of the sensing data, and calculating the actual coefficient of temperature drift 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 the temperature drift calibration value.

Further preferably, the maximum value of the set test temperature set by the temperature test box is 70°, and the minimum value is -40°.

Further preferably, the temperature test chamber adjusts the test temperature according to the following method: firstly, it is lowered from the current room temperature to -40°C, kept at -40°C for 1 hour, then heated to 70°C, and then heated to 70°C under the temperature condition of 70°C. After holding for 1 hour, the temperature began to drop, and the temperature dropped to room temperature to complete the experiment.

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 calculating the The average value is taken as the actual value of the sensing data.

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. , take the median as the actual value of the sensing data.

Further preferably, in S5, the weighted calculation of the temperature drift fitting coefficient and the temperature drift actual coefficient includes the following methods:

Among them, W is the _calibration value of temperature drift, W is the _fitting coefficient of temperature drift, and W is the _actual coefficient of temperature drift.

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

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

The invention also provides a temperature drift calibration system of 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;

The temperature-controlled test box is used to set a plurality of 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, and is used to obtain the three-dimensional deformation sensing data of each rigid sensing segment under the environment of testing temperature change;

The host computer takes the set test temperature as the independent variable, and the acquired three-dimensional deformation sensing data as the dependent variable, performs least squares polynomial fitting, and obtains the fitting formula of temperature-three-dimensional deformation sensing data; value as an independent variable, input the fitting formula of temperature-three-dimensional deformation induction data, obtain the fitting value of the induction data, and calculate the temperature drift fitting coefficient according to the fitting value of the induction data and the test temperature value; , perform statistical calculation on all three-dimensional deformation sensing data, take the statistical calculation result as the actual value of the sensing data, and calculate the actual coefficient of temperature drift according to the actual value of the sensing data and the test temperature value; Carry out weighted calculation to obtain the calibration value of temperature drift.

Further preferably, the MEMS three-dimensional deformation monitor includes multiple sets of connected rigid sensing segments and flexible joints, each group of the rigid sensing segments is connected to another set of flexible joints, and the rigid sensing segments are Built-in MEMS three-dimensional deformation sensor.

Further preferably, the length of the rigid sensing segment is 0.5m, 1m, 1.5m, the maximum value of the set test temperature set by the temperature test box is 70°, and the minimum value is -40°

In an embodiment of the present invention, firstly, the MEMS three-dimensional deformation monitor is connected in the order of rigid sensing segment, flexible joint, rigid sensing segment, and flexible joint, and the connected MEMS three-dimensional deformation monitor is put into in a temperature-controlled laboratory box. (2) Set the temperature parameters of the temperature control experiment box, the temperature parameter setting range is -40° to 70°. (3) The MEMS three-dimensional deformation monitor inside the experimental box is connected to the acquisition device, and the acquisition device collects the data of the MEMS three-dimensional deformation monitor inside the experimental box. (4) Solve the data, process the data of the MEMS three-dimensional deformation monitor through the least square polynomial fitting formula, and obtain the formula for correcting the temperature drift. The specific experimental process after the temperature of the temperature-controlled experimental box is set, is first lowered from the current room temperature to -40°, kept for 1 hour under the -40° temperature condition, then heated to 70°, and kept under the 70° temperature condition. After 1 hour, the temperature was lowered to room temperature and the experiment was completed.

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, and The curve is not required to pass through these points exactly, but an approximation of the curve y=f(x), y=[phi](x). In general, increasing the order of the fitting polynomial cannot improve the fitting accuracy, and the collected data curve is also an arc, so the order of the polynomial fitting is second-order. The second-order calculation formula is as follows:

y=a ₀ +a ₁ x+a ₂ x ²

The quadratic fitting of the least squares method is used to obtain the fitting formula of temperature-three-dimensional deformation induction data after fitting.

In the description of this specification, description with reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., mean specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and those of ordinary skill in the art will not depart from the principles and spirit of the present invention Variations, modifications, substitutions, and alterations to the above-described embodiments are possible within the scope of the present invention without departing from the scope of the present invention. The scope of the invention is defined by the appended claims and their equivalents.

Claims (9)

1. A temperature drift calibration method for an MEMS three-dimensional deformation monitor is characterized by comprising the following steps:

s1, setting a plurality of test temperatures in a temperature control test box; acquiring three-dimensional deformation sensing data of each rigid sensing section in an environment with test temperature change by using an MEMS three-dimensional deformation monitor;

s2, taking the set test temperature as an independent variable and the obtained three-dimensional deformation induction data as a dependent variable, and performing least square polynomial fitting to obtain a fitting formula of the temperature-three-dimensional deformation induction data;

s3, inputting any test temperature value as an independent variable into a fitting formula of temperature-three-dimensional deformation sensing data to obtain a sensing data fitting value, and calculating a 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 at the test temperature value in S3, taking a statistical calculation result as a sensing data actual value, and calculating a temperature drift actual coefficient according to the sensing data actual value and the test temperature value;

and S5, carrying out weighted calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain a temperature drift calibration value.

2. The temperature drift calibration method for the MEMS three-dimensional deformation monitor according to claim 1, wherein the set test temperature set by the temperature test chamber has a maximum value of 70 degrees and a minimum value of-40 degrees.

3. The temperature drift calibration method for the MEMS three-dimensional deformation monitor according to claim 2, wherein the temperature test chamber adjusts the test temperature according to the following method:

firstly, the current room temperature is reduced to-40 ℃, the temperature is kept for 1 hour under the condition of-40 ℃, then the temperature is increased to 70 ℃, the temperature is reduced after the temperature is kept for 1 hour under the condition of 70 ℃, and the experiment is finished when the temperature is reduced to the room temperature.

4. The MEMS three-dimensional deformation monitor temperature drift calibration method according to claim 1, wherein the statistical calculation of all three-dimensional deformation sensing data under the test temperature value comprises the following steps:

and 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.

5. The MEMS three-dimensional deformation monitor temperature drift calibration method according to claim 1, wherein the statistical calculation of all three-dimensional deformation sensing data under the test temperature value comprises the following steps:

and (3) solving a median of the three-dimensional deformation sensing data acquired by each rigid sensing segment under the test temperature value, and taking the median as an actual value of the sensing data.

6. The MEMS three-dimensional deformation monitor temperature drift calibration method as claimed in claim 1, wherein in S5, the weighted calculation of the temperature drift fitting coefficient and the temperature drift actual coefficient comprises the following steps:

；

wherein, W _Calibration Is a temperature drift calibration value, W _{Fitting of} Is a temperature drift fitting coefficient, W _{Practice of} Is the actual coefficient of temperature drift.

7. A temperature drift calibration system of an MEMS three-dimensional deformation monitor is characterized by comprising a temperature control test box, the MEMS three-dimensional deformation monitor, a collection device and an upper computer;

the temperature control test box is used for setting a plurality of test temperatures, including setting the maximum value and the minimum value of the test temperatures;

the MEMS three-dimensional deformation monitor comprises an internal MEMS three-dimensional deformation sensor;

the acquisition equipment is connected with each MEMS three-dimensional deformation sensor and is used for acquiring three-dimensional deformation sensing data of each rigid sensing section in the environment of test temperature change;

the upper computer performs least square polynomial fitting by taking the set test temperature as an independent variable and the acquired three-dimensional deformation induction data as a dependent variable to obtain a fitting formula of the temperature-three-dimensional deformation induction data; inputting any test temperature value as an independent variable into a fitting formula of temperature-three-dimensional deformation sensing data to obtain a sensing data fitting value, and calculating a temperature drift fitting coefficient according to the sensing data fitting value and the test temperature value; performing statistical calculation on all three-dimensional deformation sensing data at a test temperature value, taking a statistical calculation result as a sensing data actual value, and calculating a temperature drift actual coefficient according to the sensing data actual value and the test temperature value; and performing weighted calculation on the temperature drift fitting coefficient and the temperature drift actual coefficient to obtain a temperature drift calibration value.

8. The MEMS three-dimensional deformation monitor temperature drift calibration system as recited in claim 7, wherein the MEMS three-dimensional deformation monitor comprises a plurality of groups of rigid sensing segments and flexible joints which are connected, each group of rigid sensing segments is connected with another group of flexible joints, and MEMS three-dimensional deformation sensors are arranged in the rigid sensing segments.

9. The MEMS three-dimensional deformation monitor temperature drift calibration system according to claim 8, wherein the rigid sensing segment has different lengths of 0.5m, 1m and 1.5m, the set test temperature set in the temperature test chamber has a maximum value of 70 degrees and a minimum value of-40 degrees.

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