Simple calibration device and calibration method for thin film type pressure sensor

Abstract

The simple calibration device comprises a calibration cylinder body, a pressure transmitting medium is stored in the calibration cylinder body, a calibrated thin film type pressure sensor and a reference thin film type pressure sensor are arranged on the inner bottom surface of the calibration cylinder body, and the calibrated thin film type pressure sensor and the reference thin film type pressure sensor are in direct contact with the pressure transmitting medium in the calibration cylinder body. A bearing piston is arranged in the calibration cylinder body, the lower portion of the bearing piston makes contact with the surface of the pressure transmitting medium, and a drop hammer device is arranged above the bearing piston. According to the method, through the innovative structural design and the simplified calibration process, on the basis of protecting the piezoelectric film of the sensor, the calibration precision and efficiency can be effectively improved, the high requirements for professional equipment and technologies in a traditional calibration method are avoided, and the calibration operation difficulty is reduced.

Description

Technical Field

[0001] The present invention relates to the field of test and measurement sensor devices, and particularly to a simple calibration device and calibration method for a thin-film pressure sensor. Background Art

[0002] Due to its advantages such as simple structure, fast response speed, and high sensitivity, the thin-film pressure sensor is widely used in fields such as automotive electronics, industrial automation, medical equipment, and consumer electronics. When the thin-film pressure sensor is pressurized, the resistance between the corresponding electrode points on the upper and lower electrode layers changes, and the pressure received at the corresponding position of the thin-film pressure sensor is calculated based on the change in resistance between the corresponding electrode points. To ensure the measurement accuracy of the thin-film pressure sensor, it is necessary to calibrate the thin-film pressure sensor regularly. The calibration of the pressure sensor is a complex process involving multiple steps and multiple tools, requiring professional technology and equipment. Most of the existing pressure sensor calibration devices are designed for traditional threaded-interface pressure sensors and cannot be applied to new sensors without threaded interfaces, such as polyvinylidene fluoride (PVDF) thin-film pressure sensors; the existing calibration methods for thin-film pressure sensors usually require high-precision test equipment and complex operation procedures, and the calibration process is cumbersome and time-consuming. At the same time, due to the special structure of the thin-film pressure sensor, when the rigid calibration device in the prior art applies pressure to the thin-film pressure sensor, it is particularly easy to damage the thin-film pressure sensor, causing irreparable damage to the thin-film pressure sensor.

[0003] Pressure sensor calibration is divided into static and dynamic methods. During static calibration, the pressure loading time at the calibration point is relatively long, and the long pressure loading time seriously affects the service life of the sensor. Dynamic calibration effectively solves this problem. Common dynamic calibration methods include the shock tube method and the drop hammer method. Among them, since the step pressure platform generated by the shock tube method has a short duration, it cannot be used to calibrate the thin-film pressure sensor; to make up for this deficiency, the drop hammer hydraulic dynamic calibration method is a relatively feasible option; this calibration method is between static and dynamic, and uses a semi-sine pressure pulse similar to the measured pressure waveform, that is, a known peak value and pulse width, to calibrate the thin-film pressure sensor; the sensitivity of the pressure sensor given by this calibration method is more scientific and accurate than that of the static calibration method, and can effectively reduce the dynamic error of the measurement system.

[0004] The calibration pressure of the drop hammer device is generated by the impact of a weight on the piston rod within the calibration cylinder. This pressure is a pressure pulse similar to a half-sine wave, and the magnitudes of its peak value and pulse width are related to the operating parameters of the drop hammer device (such as the drop height of the weight, the mass of the weight, the area of the piston rod, the pressure transmission medium, the initial volume of the calibration cylinder, etc.). Accurately obtaining the peak value of the half-sine pressure pulse is the key to effectively using the drop hammer device for quasi-static calibration of pressure sensors. A monitoring pressure dynamic calibration method based on the drop hammer device is proposed. That is, according to the internal relationship between the force of the weight impacting the piston rod (impact force) and the pressure peak value, a reference sensor is installed within the calibration cylinder to monitor the impact force, thereby obtaining the corresponding calibration pressure peak value. This method directly calibrates according to the definition of pressure, which is more in line with the definition of absolute calibration and can effectively improve the calibration accuracy of dynamic pressure. Summary of the Invention

[0005] The object of the present invention is to overcome the problems existing in the existing pressure sensor calibration devices, such as being unable to fully apply to polyvinylidene fluoride (PVDF) thin film sensors without threaded interfaces, complex calibration processes, and inability to guarantee calibration accuracy. A simple calibration device and calibration method for thin film pressure sensors that are not easily damaged are provided. Through innovative structural design and simplified calibration processes, on the basis of protecting the piezoelectric film of the sensor, it can effectively improve calibration accuracy and efficiency, avoid the high requirements for professional equipment and technology in traditional calibration methods, and reduce the difficulty of calibration operations.

[0006] A simple calibration device for thin film pressure sensors includes a calibration cylinder. The calibration cylinder stores a pressure transmission medium. The inner bottom surface of the calibration cylinder is provided with a thin film pressure sensor to be calibrated and a reference thin film pressure sensor, and both are in direct contact with the pressure transmission medium within the calibration cylinder. A load-bearing piston is provided within the calibration cylinder. The lower part of the load-bearing piston is in contact with the surface of the pressure transmission medium, and a drop hammer device is arranged above the load-bearing piston.

[0007] Further, the calibration cylinder includes a sleeve and a bottom plate; the sleeve is located above the bottom plate, and the sleeve is fixed in the center of the bottom plate.

[0008] Further, the drop hammer device includes a weight and a descending tube; the descending tube is located outside the sleeve, the surface of the descending tube is higher than the load-bearing piston, and the weight is located inside the descending tube.

[0009] Further, it also includes a cylindrical rod. Through holes are evenly distributed on the outer wall of the descending tube, and the cylindrical rod is inserted into the corresponding through holes to restrict the weight from sliding along the inner wall.

[0010] Further, the pressure transmission medium is liquid silicone oil.

[0011] Further, the upper end of the bearing piston has a bearing surface that can be used to bear the falling pressure of the weight in the downcomer. The lower end is closely fitted with the inner wall of the sleeve. The falling of the weight acts on the bearing surface of the bearing piston to generate a calibration pressure. The bearing piston moves vertically downward, and the calibration pressure acts on the reference thin-film pressure sensor and the calibrated thin-film pressure sensor through the liquid silicone oil inside the calibration cylinder block.

[0012] Further, the bearing piston is made of alloy structural steel with strong yield stiffness, and the acceleration of the falling weight can be completely converted into calibration pressure.

[0013] Further, it is characterized in that: it further includes a device support. The device support includes an upper layer of the device support and a middle layer of the device support. The downcomer is fixed in the vertical direction through the upper layer of the device support and the middle layer of the device support.

[0014] Further, it further includes a collection device. The collection device includes a signal conditioner, a data acquisition system, and a computer. The signal conditioner is communicatively connected to the pressure sensors in the calibrated thin-film pressure sensor and the reference thin-film pressure sensor. The signal conditioner adjusts and processes the output signals of the pressure sensors to meet the set requirements and outputs them to the data acquisition system (80). The data acquisition system automatically acquires the electrical signals output by the pressure sensors and outputs them to the upper computer, and then combines with a specific program to complete the calibration operation of the calibrated thin-film pressure sensor.

[0015] A calibration method for a simple calibration device of a thin-film pressure sensor is as follows:

[0016] Step 1: Install the pressure sensors of the calibrated thin-film pressure sensor and the reference thin-film pressure sensor at the bottom of the calibration cylinder block through the mounting grooves on the upper end surface of the bottom plate and communicate with the liquid silicone oil inside the cylinder block. Place the weight in the downcomer, set the falling height, and let the weight freely fall to hit the upper end surface of the bearing piston to generate pressure in the calibration cylinder, and the pressure acts on the calibrated thin-film pressure sensor and the reference thin-film pressure sensor at the same time.

[0017] Step 2: Calculate the peak pressure of the liquid silicone oil in the calibration cylinder block based on the peak impact force measured by the pressure sensor in the reference thin-film pressure sensor and the effective area of the bearing piston, and use it as the reference pressure value of the pressure sensor in the calibrated thin-film pressure sensor.

[0018] Step 3: Form a set of data pairs with the calculated reference pressure peak and the output voltage peak of the pressure sensor in the corresponding calibrated thin-film pressure sensor. Change the falling height and conduct multiple groups of tests within the range of the pressure sensor in the calibrated thin-film pressure sensor to obtain multiple groups of data pairs of pressure peaks and voltage peaks.

[0019] Step 4: Perform least squares fitting on the above data pairs. According to the fitting relationship formula, the sensitivity value of the electrical measurement system in the thin-film pressure sensor to be calibrated can be obtained, thus completing the quasi-static calibration of the pressure sensor in the thin-film pressure sensor to be calibrated.

[0020] The beneficial effects of the present invention are as follows:

[0021] 1. Install the thin-film pressure sensor to be calibrated and the reference thin-film pressure sensor at the bottom of the calibration cylinder block simultaneously. The calibration pressure acts on the thin-film pressure sensor to be calibrated and the reference thin-film pressure sensor at the same time, making the measured pressure data more accurate with smaller errors. At the same time, there is no need to install the reference sensor with redundant structural parts, and the overall structure of the calibration device is more compact and simple.

[0022] 2. The inner cavity of the calibration cylinder is filled with silicone oil as the pressure transmission medium. The calibration pressure generated by the falling weight is transmitted to the thin-film pressure sensor through the pressure transmission medium, which is not easy to damage the thin-film pressure sensor.

[0023] 3. Effectively reduce the rebound force generated by the collision of the bearing piston moving towards the bottom plate in the calibration cylinder, and improve the impact force test accuracy of the drop hammer device. Description of the Drawings

[0024] Figure 1 Schematic diagram of the main structure of the simple calibration device for thin-film pressure sensors;

[0025] Figure 2 Schematic diagram of the main cross-section of the simple calibration device for thin-film pressure sensors;

[0026] Figure 3 Schematic diagram of the overall structure of the simple calibration device for thin-film pressure sensors;

[0027] Figure 4 Schematic three-dimensional diagram of the overall structure of the simple calibration device for thin-film pressure sensors;

[0028] Figure 5 Schematic diagram of the auxiliary markings of the overall structure of the simple calibration device for thin-film pressure sensors;

[0029] Figure 6 Simple calibration device for thin-film pressure sensors Figure 5 Cross-section schematic diagram at position Ⅰ in;

[0030] Figure 7 Simple calibration device for thin-film pressure sensors Figure 5 Cross-section schematic diagram at position Ⅱ in;

[0031] Figure 8 Schematic diagram of the downcomer structure;

[0032] Figure 9Schematic diagram of the overall simple calibration device and acquisition equipment for a thin-film pressure sensor;

[0033] Figure 10 Test data diagram of the simple calibration device for a thin-film pressure sensor;

[0034] Figure 11 Test average result diagram of the simple calibration device for a thin-film pressure sensor.

[0035] Among them, downcomer - 10, device support main body - 20, upper layer of device support - 201, middle layer of device support - 202, bottom layer of device support - 203, cylindrical rod - 30, placement plane - 40, calibration device - 50, load piston - 501, sleeve - 502, upper disc flange - 503, lower disc flange - 504, thin-film pressure sensor to be calibrated - 505, reference thin-film pressure sensor - 506, bottom plate - 507, base - 508, liquid silicone oil - 509, weight - 60, signal conditioner - 70, data acquisition system - 80, computer - 90. Specific implementation manner

[0036] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0037] The present invention provides a simple calibration device and calibration method for a thin-film pressure sensor. This method can not only be fully applicable to polyvinylidene fluoride (PVDF) thin-film sensors without threaded interfaces, but also is not likely to damage the piezoelectric film of the thin-film pressure sensor.

[0038] Such as Figure 1 And Figure 2As shown in the figure, a simple calibration device for a thin-film pressure sensor according to the present invention, the calibration device 50 includes a bearing piston 501, a sleeve 502, an upper disc flange 503, a lower disc flange 504, a thin-film pressure sensor to be calibrated 505, a reference thin-film pressure sensor 506, a bottom plate 507, a base 508, and liquid silicone oil 509. The base 508 plays a role in supporting and connecting. The bottom plate 507 is fixedly installed on the upper surface of the base 508 through threaded holes. The sleeve 502 is a cylindrical hollow sleeve and is arranged on the upper surface of the bottom plate 507. Both the upper disc flange 503 and the lower disc flange 504 are 8-hole flange plates and are fixedly installed at the reserved installation positions on the upper surface of the bottom plate 507 by screws in cooperation with each other, and at the same time, the sleeve 502 is fixed. The sleeve 502, the upper disc flange 503, the lower disc flange 504, and the bottom plate 507 form a calibration cylinder body, and the bottom of the calibration cylinder body is filled with liquid silicone oil 509; the bottom plate 507 is processed with an installation groove with a depth of 1-2 mm. The thin-film pressure sensor to be calibrated 505 and the reference thin-film pressure sensor 506 are symmetrically arranged in the installation groove. The upper surfaces of the thin-film pressure sensor to be calibrated 505 and the reference thin-film pressure sensor 506 communicate with the inner cavity of the calibration cylinder body and are in direct contact with the silicone oil in the cavity; the upper end of the bearing piston 501 is designed with a force-bearing surface, and the lower end is in close fit with the inner wall of the sleeve 502. After the force-bearing surface is stressed, the bearing piston 501 can move in a vertical direction and transmit the force to the liquid silicone oil 509 in the inner cavity of the calibration cylinder body, and it serves as a pressure transmission medium to transmit the force to the thin-film pressure sensor to be calibrated 505 and the reference thin-film pressure sensor 506 at the bottom of the calibration cylinder body; preferably, this structure avoids the direct contact between the rigid bearing piston and the thin-film pressure sensor, effectively avoids the damage of the piezoelectric film of the sensor due to stress, and at the same time enables the pressure to act evenly on the surface of the pressure sensor, making its calibration result more accurate and reliable.

[0039] As Figure 3 and Figure 4 shown in the figure, it is the overall structure of the calibration device according to the present invention. A device bracket is arranged outside the device main body, including a device bracket main body 20, a device bracket upper layer 201, a device bracket middle layer 202, and a device bracket bottom layer 203, which are used to keep the device structure stable and play roles of supporting, fixing, and connecting; the calibration device 50 is fixed at the center position on the upper surface of the placement plane 40 through the installation holes at the bottom of the base 508. The placement plane 40 is fixed to the device bracket bottom layer 203. A downcomer 10 with a size of 1 m is vertically installed on the upper part of the calibration device 50. In order to prevent the downcomer 10 from shaking under stress and deviating from the required position during the calibration process, which will affect the calibration operation, the device bracket upper layer 201 and the device bracket middle layer 202 respectively clamp the upper and lower positions of the downcomer 10 to achieve horizontal fixation; this design scheme makes the overall structure more stable and reliable, and greatly reduces the experimental error.

[0040] As Figure 5 、Figure 6 and Figure 7 As shown in Figure 7 , before calibrating the sensor to be calibrated, a weight 60 made of cemented carbide is placed inside the downcomer 10. The downcomer 10 is as Figure 8 shown. Through holes are evenly distributed on the outer wall of the downcomer at intervals of 100 mm. The weight 60 is placed in the downcomer 10, and at the same time, the cylindrical rod 30 is inserted into the corresponding through holes to limit the sliding of the weight 60 along the inner wall. When calibrating the thin-film pressure sensor 505 to be calibrated, the cylindrical rod 30 is quickly withdrawn. The weight 60 slides down rapidly under the action of gravity and collides rigidly with the bearing surface of the bearing piston 501 at the bottom of the downcomer 10. At the moment of collision, the gravitational acceleration of the weight 60 is completely converted into the pressure in the calibration cylinder and transmitted through the pressure transmission medium, liquid silicone oil 509, to the thin-film pressure sensor 505 to be calibrated and the reference thin-film pressure sensor 506 at the bottom of the calibration cylinder; through holes are evenly distributed on the outer wall of the downcomer 10. By inserting the cylindrical rod 30 into through holes at different heights, the falling height of the weight 60 and the pressure inside the calibration cylinder can be changed; preferably, the falling time and falling height of the weight 60 can be controlled by the downcomer 10 with through holes in cooperation with the cylindrical rod 30, greatly avoiding the accidental errors caused by the falling of the weight 60 during the calibration operation, and at the same time ensuring the repeatability of the operation, making the calibration result more reliable.

[0041] As Figure 9 shown, the present invention relates to a simple calibration device and acquisition equipment for a thin-film pressure sensor. The calibration data acquisition equipment includes a signal conditioner 70, a data acquisition system 80, and a computer 90; the signal conditioner 70 is communicatively connected to the pressure sensor. The signal conditioner 70 adjusts and processes the output signal of the pressure sensor to meet the set requirements and outputs it to the data acquisition system 80. The data acquisition system 80 automatically acquires the electrical signal output by the pressure sensor and outputs it to the computer 90, and then combines with a specific program to complete the calibration operation of the thin-film pressure sensor to be calibrated.

[0042] Preferably, the simple calibration device for the thin-film pressure sensor can perform precise dynamic calibration on the pressure sensor within a medium pressure range (200 to 15000 psi). The pressure pulse acts on the reference thin-film pressure sensor and the thin-film pressure sensor to be calibrated simultaneously to determine the sensitivity of the pressure sensor at a specific amplitude, and the amplitude level is changed by changing the falling height of the weight 60.

[0043] The steps of the simple calibration device and calibration method for the thin-film pressure sensor based on the drop hammer device of the present invention are as follows:

[0044] 1) Install the thin-film pressure sensor 505 to be calibrated and the reference thin-film pressure sensor 506 at the bottom of the calibration cylinder through the mounting grooves of the bottom plate 507 and make direct contact with the internal pressure transmission medium. The weight 60 is loaded into the downcomer 10, the cylindrical rod 30 is inserted, and the falling height is set;

[0045] 2) The calibration operation starts. The cylindrical rod 30 is quickly withdrawn, and the weight 60 collides with the bearing piston 501, generating pressure inside the calibration cylinder.

[0046] 3) Based on the peak impact force measured by the reference thin-film pressure sensor 506 and the effective area of the bearing piston 501, calculate the peak pressure of the pressure transmission medium inside the calibration cylinder, which is used as the reference pressure value for the thin-film pressure sensor 505 to be calibrated.

[0047] 4) Form a set of data pairs with the obtained reference pressure peak and the peak output voltage of the thin-film pressure sensor 505 to be calibrated. Change the falling height and conduct multiple groups of tests within the range of the thin-film pressure sensor to obtain multiple groups of data pairs of pressure peaks and voltage peaks.

[0048] 5) Perform least squares fitting on the above data. According to the fitting relationship, the sensitivity value of the thin-film pressure sensor system can be obtained, thus completing the absolute quasi-static calibration work.

[0049] The present invention records the instantaneous outputs of the thin-film pressure sensor 505 to be calibrated and the reference thin-film pressure sensor 506 after the pulse, measures the peak voltage outputs of the thin-film pressure sensor 505 to be calibrated and the reference thin-film pressure sensor 506, and uses three values (two voltage measurement values and a known reference sensitivity) to calculate the sensitivity of the thin-film pressure sensor 505 to be calibrated. The measured data and results are processed and collected by the signal conditioner 70 and the data acquisition system 80 and then displayed in the computer 90; the displayed data allows the operator to view the waveform and check for abnormalities in the pressure pulse; the linear graph (as Figure 10 shown) displays an overview of the test results in real time; the software automatically calculates values such as sensitivity, pressure level, and pulse duration; the result table provides an image of the average results of all tests, as Figure 11 shown.

[0050] In order to obtain the sensitivity of the thin-film pressure sensor to be calibrated, it is necessary to perform static calibration on it. When calibrating, six calibration points of 0 kN, 20 kN, 40 kN, 60 kN, 80 kN, and 100 kN are selected, and three rounds of forward and reverse stroke calibrations are performed to obtain the static calibration results. According to the calibration results, the static characteristic parameters of the thin-film pressure sensor to be calibrated are obtained.

[0051] The basic parameters of the present invention are as follows: typical rise time 3 ms, typical pulse duration 6 - 8 ms, sensitivity 0.2 Pc / psi, measurement range 15000 psi, resolution 0.5 psi, resonant frequency ≥ 1.0 MHz, linearity ≤ 0.5% FS.

[0052] The above embodiments are only the preferred embodiments of the present invention, and the scope of protection of the present invention cannot be limited thereby. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention fall within the scope of protection required by the present invention.

Claims

1. A simple calibration device for a thin-film pressure sensor, characterized in that: It includes a calibration cylinder body in which a pressure transmission medium is stored. On the inner bottom surface of the calibration cylinder body, a calibrated thin-film pressure sensor (505) and a reference thin-film pressure sensor (506) are provided, and both are in direct contact with the pressure transmission medium in the calibration cylinder body. A load piston (501) is provided in the calibration cylinder body. The lower part of the load piston (501) is in contact with the surface of the pressure transmission medium, and a drop hammer device is provided above the pressure-bearing piston (501).

2. The simple calibration device for a thin-film pressure sensor according to claim 1, wherein: The calibration cylinder body includes a sleeve (502) and a bottom plate (507); the sleeve (502) is located above the bottom plate (507), and the sleeve (502) is fixed at the center of the bottom plate (507).

3. An easy calibration device for a thin-film pressure sensor according to claim 2, characterized in that: The drop hammer device includes a weight (60) and a drop tube (10); the drop tube (10) is located outside the sleeve (502), and the surface of the drop tube (10) is higher than the load piston (501), and the weight (60) is located inside the drop tube (10).

4. The simple calibration device for a thin-film pressure sensor according to claim 3, characterized in that: It further includes a cylindrical rod (30). Through holes are evenly distributed on the outer wall of the drop tube (10), and the cylindrical rod (30) is inserted into the corresponding through holes to limit the weight (60) from sliding along the inner wall.

5. The simple calibration device for a thin-film pressure sensor according to claim 4, characterized in that: The pressure transmission medium is liquid silicone oil (509).

6. The simple calibration device for a thin-film pressure sensor according to claim 5, characterized in that: The upper end of the load piston (501) has a bearing surface that can be used to bear the falling pressure of the weight (60) in the drop tube (10). The lower end is closely fitted with the inner wall of the sleeve (502). The falling of the weight (60) acts on the bearing surface of the load piston (501) to generate a calibration pressure. The load piston (501) moves vertically downward, and the calibration pressure acts on the reference thin-film pressure sensor (506) and the calibrated thin-film pressure sensor (505) through the liquid silicone oil (509) inside the calibration cylinder body.

7. An easy calibration device for a thin-film pressure sensor according to claim 6, characterized in that: The load piston (501) is made of alloy structural steel with strong yield stiffness, and the acceleration of the falling weight (60) can be completely converted into a calibration pressure.

8. An easy calibration device for a thin-film pressure sensor according to claim 7, characterized in that: It further includes a device support. The device support includes an upper layer (201) and a middle layer (202) of the device support. The drop tube (10) is fixed in the vertical direction through the upper layer (201) and the middle layer (202) of the device support.

9. The simple calibration device for a thin-film pressure sensor according to claim 8, characterized in that: It further includes a collection device. The collection device includes a signal conditioner (70), a data acquisition system (80), and a computer (90); the signal conditioner (70) is communicatively connected to the pressure sensors in the calibrated thin-film pressure sensor (505) and the reference thin-film pressure sensor (506). The signal conditioner (70) adjusts and processes the output signals of the pressure sensors to meet the set requirements and outputs them to the data acquisition system (80). The data acquisition system (80) automatically collects the electrical signals output by the pressure sensors and outputs them to the upper computer (90), and then combines with a specific program to complete the calibration operation of the calibrated thin-film pressure sensor (505).

10. A calibration method for the thin-film pressure sensor simple calibration device according to claim 9, characterized in that: The specific steps are as follows: Step 1: Install the pressure sensors of the thin-film pressure sensor to be calibrated (505) and the reference thin-film pressure sensor (506) at the bottom of the calibration cylinder through the mounting grooves on the upper end surface of the bottom plate (507), and make them communicate with the liquid silicone oil (509) inside the cylinder. Place the weight (60) into the downcomer (10), set the falling height, and let the weight (60) freely fall to impact the upper end surface of the load piston (501), generating pressure in the calibration cylinder. The pressure acts on the thin-film pressure sensor to be calibrated (505) and the reference thin-film pressure sensor (506) simultaneously; Step 2: Calculate the peak pressure of the liquid silicone oil (509) in the calibration cylinder based on the peak impact force measured by the pressure sensor in the reference thin-film pressure sensor (506) and the effective area of the load piston (501), and use it as the reference pressure value for the pressure sensor in the thin-film pressure sensor to be calibrated (505); Step 3: Form a set of data pairs with the calculated reference pressure peak and the peak output voltage of the pressure sensor in the thin-film pressure sensor to be calibrated (505). Change the falling height and conduct multiple groups of experiments within the range of the pressure sensor in the thin-film pressure sensor to be calibrated (505), and obtain multiple groups of data pairs of pressure peaks and voltage peaks; Step 4: Perform least squares fitting on the above data pairs. According to the fitting relationship, the sensitivity value of the electrical measurement system in the pressure sensor of the thin-film pressure sensor to be calibrated (505) can be obtained, thus completing the quasi-static calibration work of the pressure sensor in the thin-film pressure sensor to be calibrated (505).

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