Intelligent micro-pressure measurement system

Abstract

The application realizes an intelligent micro-pressure measuring system which can accurately and quickly measure the height difference of liquid column on both sides of U-shaped tube pressure gauge and convert it into pressure signal, and continuously and accurately measure the small pressure difference in the pipeline with high precision, which comprises an aluminum profile frame for supporting and fixing the overall structure and installing various components; a U-shaped tube pressure gauge, a U-shaped pressure tube connected to the measured pipeline system for indirectly measuring the micro-pressure of the pipeline; a screw rod driven by a stepper motor, a sliding block mounted on the screw rod, the sliding block connected to the camera support through bolts, and the sliding block moving up and down through motor control; an industrial camera module installed on the moving sliding block, the camera module including an industrial camera, a lens, a light source, a micrometer and a camera support, etc., the sliding block driving the camera module to move; and an image recognition system for analyzing and identifying the picture pixels and analyzing the height difference between the liquid level and the scale of the U-shaped tube pressure gauge.

Description

Technical Field

[0001] This invention belongs to the field of pressure detection technology, specifically relating to an intelligent micro-pressure measurement system. Background Technology

[0002] Pressure is one of the key parameters of a pipeline system. Accurate measurement of minute pressures is crucial for process control and product quality. The general approach to micro-pressure measurement is to first convert the pressure signal into an intermediate signal, and then into an electrical signal to output a pressure value. Existing micro-pressure sensors typically use silicon piezoresistive elements to detect changes in medium pressure. These pressure changes cause minute displacements in the diaphragm, altering the circuit resistance. By detecting this change, a standard signal corresponding to that pressure is output. However, this approach suffers from limitations in installation, susceptibility to damage, and relatively low accuracy. Further research is needed to optimize the detection of minute pressure variations within pipelines.

[0003] Technical problems with existing technologies:

[0004] Pipelines are frequently used to transport fluids in fluid transportation or other fields. In pipeline transportation, pressure is one of the most important parameters. To accurately measure the pressure of the medium in the pipeline, micro-pressure sensors are often installed inside the pipeline.

[0005] Traditional micro-pressure sensors use silicon thin films as detection elements, which have problems such as limited installation, easy damage, low accuracy, and susceptibility to interference.

[0006] The present invention is compared with the prior art as follows:

[0007] Technical comparison with patent CN103217252A_A mobile container-type high-precision micro-pressure detection device

[0008] The method used in CN 103217252A:

[0009] Patent CN103217252A proposes a mobile container-type high-precision micro-pressure detection device, which uses a moiré fringe grating ruler and a laser displacement meter to achieve accurate pressure measurement.

[0010] Floats are installed on the liquid surface in both movable and fixed containers, and the floats are correspondingly set with laser displacement gauges to detect changes in the liquid level;

[0011] The actual pressure of the input gas is calculated by the vertical displacement of the movable container and the displacement of the float on the liquid surface in the fixed container and the movable container relative to the initial position.

[0012] The vertical displacement distance of the movable container is converted into the measurement of the number of moiré fringes using a grating measurement mechanism. Photoelectric devices are used to realize electronic subdivision and orientation determination within a moiré fringe, thereby obtaining the moving direction and displacement distance of the grating ruler.

[0013] Based on the principle of triangulation, the displacement of the float on the liquid surface in the fixed container and the movable container is measured from the initial position. There is a polytetrafluoroethylene diffuse reflection plane at the top of the float, which projects the reflected light onto the CCD reflector. The position of the light spot on the CCD and the distance to the float are calculated by trigonometric functions.

[0014] The pressure is generated and controlled by a microcontroller-controlled stepper motor. Both the movable and fixed containers are equipped with pressure interfaces. The movable container interface is connected to atmospheric pressure, and the fixed container interface is connected to the pressure gauge to be tested and the microcontroller controller. The controller is connected to a computer system to calculate and display the difference between the pressure to be tested and the actual pressure.

[0015] This method converts the actual pressure of the input gas into the displacement of the float relative to its initial position within the movable container and the liquid surface in both the fixed and movable containers. A striped grating ruler and a laser displacement meter are used to measure the displacement distance, and a microcontroller is used to generate and control the pressure, thus maintaining the pressure within a very small fluctuation range over a long period. However, the vertical displacement of the movable container is controlled manually, making it difficult to automate and continuously measure micro-pressure. When using floats to measure liquid surface displacement, changes in liquid density will alter the volume of the float immersed in the liquid, affecting the accuracy of the liquid level measurement. Furthermore, the float mechanism requires regular maintenance and calibration to ensure measurement accuracy, increasing operating costs and maintenance workload.

[0016] The method of the present invention:

[0017] This invention utilizes a combination of hardware and software, including a U-tube manometer, a high-resolution camera, and image recognition software, to identify the height difference between the liquid columns on both sides of the U-tube, thereby accurately and rapidly measuring the micro-pressure of the system under test, achieving automation, continuous operation, and intelligent micro-pressure measurement. The core innovation of this method is:

[0018] To expand the measurement range and improve measurement accuracy, a rectangular micrometer is used to measure the liquid level in the U-tube, with a minimum division value of 0.1 mm, which greatly improves the measurement accuracy. An image processing program is used to identify the relationship between image pixels and physical length, realizing the automation and intelligence of micro-pressure measurement.

[0019] Comparison of technical advantages

[0020] Automation, intelligence, and continuity of micro-pressure measurement: This invention uses an image processing program to identify the relationship between the smallest division value of the micrometer and the actual physical length, automatically, continuously, and quickly outputting micro-pressure measurement values. In contrast, the float measurement method used in CN103217252A requires waiting for the liquid level to stabilize, and the height of the movable container needs to be manually input into the controller, which limits the intelligence, continuity, and speed of measurement. Furthermore, the structure and principle of this invention are relatively simple and clear, easy to use, and convenient to maintain, making it superior to CN 103217252 A in terms of usage and maintenance costs.

[0021] In summary, the intelligent micro-pressure measurement system proposed in this invention is superior to CN 103217252 A in terms of rapid continuous micro-pressure measurement and cost of use and maintenance. Summary of the Invention

[0022] This invention addresses the shortcomings of existing technologies by implementing an intelligent micro-pressure measurement system that uses a combination of hardware and software, such as a U-tube manometer, a high-resolution camera, and an image recognition program, to identify the height difference of liquid columns on both sides of a U-tube, thereby achieving accurate and rapid measurement of the micro-pressure difference between two points in the system under test.

[0023] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0024] A smart micro-pressure measuring system, characterized in that it comprises:

[0025] Aluminum profile frame is used to support and fix the overall structure, forming the overall frame;

[0026] The U-tube manometer is fixed on an aluminum profile frame and connected to the pipeline system being tested. It applies the principle of hydrostatics to convert pressure into liquid column height and accurately measures the height of the liquid column, thereby indirectly measuring the micro-pressure in the pipeline system being tested.

[0027] A lead screw slide with a motor is fixed on an aluminum profile bracket. It includes a stepper motor and a lead screw. The output shaft of the stepper motor is connected to the lead screw. A movable slide is mounted on the lead screw. The movable slide is controlled by the stepper motor to move up and down.

[0028] The camera module includes a camera bracket, an industrial camera, a camera lens, a ring light source, a rectangular micrometer, and a background plate. The motion slide is connected to the camera bracket by bolts. The background plate is fixed to the industrial camera on the camera bracket. The camera lens, ring light source, and rectangular micrometer are sequentially arranged between the two. The camera lens is mounted on the industrial camera. The ring light source and rectangular micrometer are respectively fixed on the camera bracket. The camera lens passes through the ring light source and is positioned directly opposite the rectangular micrometer. The relative position of the rectangular micrometer in the field of view of the camera lens is fixed. The industrial camera magnifies the images of the liquid column surface, the scale, and the rectangular micrometer at a preset position and transmits them to an image recognition system.

[0029] An image recognition system is used to analyze and identify image pixels. The industrial camera is connected to the image recognition system and receives the image data transmitted by it. The system determines the correspondence between pixels and actual length through the scale on the rectangular micrometer, and uses this relationship to analyze the height difference between the liquid column height and the scale of the U-tube manometer, identify the height difference of the liquid columns on both sides, and thus measure the small pressure difference in the pipeline.

[0030] As a preferred embodiment of the present invention: the U-tube manometer includes a U-tube, the U-tube being marked with a scale, and both ends of the U-tube having connection ports that are respectively connected to the pipeline system being measured. The pressure on one side of the pipeline is:

[0031] P=ρgh (1)

[0032] In the formula, h is the height of the liquid column on one side of the U-shaped tube, ρ is the density of the working fluid, and g is the acceleration due to gravity.

[0033] As a preferred technical solution of the present invention: the U-shaped tube is provided with a working fluid, which is one of water, alcohol or mercury. The working fluid in the U-shaped tube is immiscible with the fluid inside the pipeline system under test, and has stable physical properties and known density. When measuring the micro pressure difference of the pipeline system under test, both ends of the U-shaped tube are connected to the pipeline system under test. The pressure difference corresponding to the height difference Δh of the liquid columns on both sides is the micro pressure difference of the pipeline system under test, which is calculated using formula (1).

[0034] As a preferred technical solution of the present invention: the spiral screw is connected to the output shaft of the stepper motor through a coupling. The stepper motor is equipped with a power supply and a controller. By controlling the rotation direction, number of rotation steps and rotation speed of the stepper motor rotor, the position of the motion slide on the spiral screw is changed, thereby changing the position of the camera module so that it can simultaneously include the U-shaped tube liquid surface, the scale and the rectangular micrometer in the field of view.

[0035] As a preferred technical solution of the present invention: limit switches are respectively installed on the upper and lower parts of the spiral screw, and the limit switches are connected to the controller. When the moving slide moves to the preset position, the limit switch detects the signal and transmits it to the controller. The controller shuts down the stepper motor, and the moving slide stops moving.

[0036] As a preferred technical solution of the present invention: the industrial camera is connected to the image recognition system via HDMI, the camera lens is a zoom lens, and the horizontal distance between the camera lens and the scale of the U-tube manometer is 7-9cm.

[0037] As a preferred technical solution of the present invention: the ring light source and the rectangular micrometer are both fixed on the camera bracket by a clamp, and the rectangular micrometer is placed close to the scale of the U-tube pressure gauge.

[0038] As a preferred technical solution of the present invention: the minimum grid value of the rectangular micrometer is 0.1mm. By calibrating the pixel corresponding to the minimum grid value in the image, the relationship between the physical height and the image pixels is obtained. This relationship can be used to calculate the pressure corresponding to the height of the liquid column.

[0039] As a preferred technical solution of the present invention: the image recognition system includes a calibration mechanism, an adjustment mechanism, a recognition mechanism, an output mechanism, and a judgment mechanism. The calibration mechanism is used to calibrate the pixels of the received image, where X pixels equal 0.01 mm. The adjustment mechanism is used to adjust the height, movement speed, and direction. The recognition mechanism includes a scale recognition mechanism and a liquid level recognition mechanism. The scale recognition mechanism is used to recognize the scale height and output the scale height H. The liquid level recognition mechanism is used to recognize the pixel corresponding to the difference between the lowest point of the liquid level and the scale height and convert it into a height h. The output mechanism is used to output the liquid level height, where the liquid level height H1 = H + h. The judgment mechanism is used to determine whether to measure the liquid level height on both sides. If yes, it directly outputs the pressure value, P = ρ * g * ΔH, where h is the height of the liquid column on one side of the U-shaped tube, ρ is the density of the measured liquid, g is the gravitational acceleration constant, and ΔH = H1 - H2. If no, the height, movement speed, and direction are readjusted through the adjustment mechanism.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] This invention features a simple structure, robust durability, easy reading, and reliable data.

[0042] Using a rectangular micrometer instead of a ruler for reading greatly improves measurement accuracy and reduces systematic and indication errors, thus enabling more precise measurement of the micro-pressure difference between two points in the pipeline system under test.

[0043] A stepper motor is installed at the top of the screw, which converts the rotational motion into the axial linear motion of the camera module and the rectangular micrometer. The controller controls the rotation direction and speed of the stepper motor, thereby controlling the position of the camera module and the rectangular micrometer, and thus ensuring that the liquid level is always within the field of view of the camera lens.

[0044] An image recognition system is used to identify the correspondence between pixels and the smallest scale of a micrometer. This relationship is then used to indirectly measure the height of the liquid column, thus achieving automation and precision in micro-pressure measurement. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of the structure of the present invention;

[0046] Figure 2 This is a schematic diagram of a lead screw slide with a motor.

[0047] Figure 3 A schematic diagram of the structure of each part of the camera module;

[0048] Figure 4 A schematic diagram of the aluminum profile frame that forms the overall frame;

[0049] Figure 5 This is a flowchart of the image recognition system operation.

[0050] Figure 6 This is a physical illustration of the present invention.

[0051] List of reference numerals in the attached diagram:

[0052] 1. Aluminum profile frame; 2. U-tube manometer; 3. Screw slide with motor; 4. Camera module; 5. Stepper motor; 6. Helical screw; 7. Motion slide; 8. Camera bracket; 9. Industrial camera; 10. Camera lens; 11. Ring light source; 12. Rectangular micrometer; 13. Background board. Detailed Implementation

[0053] To make the above-mentioned objectives, features, and advantages of the present invention more apparent and understandable, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] Please refer to the instruction manual appendix. Figure 1-6 The present invention provides a technical solution: an intelligent micro-pressure measuring system, comprising:

[0055] Aluminum profile frame 1 is used to support and fix the overall structure, forming the overall frame;

[0056] U-tube manometer 2, which is fixed on aluminum profile frame 1, is connected to the pipeline system to be measured. It applies the principle of hydrostatic pressure to convert pressure into liquid column height and accurately measures the height of the liquid column, thereby indirectly measuring the pipeline micro-pressure in the pipeline system to be measured.

[0057] The lead screw slide 3 with motor is fixed on the aluminum profile bracket and includes a stepper motor 5 and a helical lead screw 6. The output shaft of the stepper motor 5 is connected to the helical lead screw 6. The helical lead screw 6 is equipped with a motion slide 7. The motion slide 7 is controlled by the stepper motor 5 to move up and down.

[0058] Camera module 4 includes camera bracket 8, industrial camera 9, camera lens 10, ring light source 11, rectangular micrometer 12, and background plate 13. The motion slide 7 is connected to camera bracket 8 by bolts. The background plate 13 is fixed to camera bracket 8 relative to industrial camera 9. Camera lens 10, ring light source 11, and rectangular micrometer 12 are arranged sequentially between the two. Camera lens 10 is mounted on industrial camera 9. Ring light source 11 and rectangular micrometer 12 are respectively fixed on camera bracket 8. Camera lens 10 is set through ring light source 11 and directly opposite rectangular micrometer 12. The relative position of rectangular micrometer 12 in the field of view of camera lens 10 is fixed. Industrial camera 9 magnifies and transmits the images of liquid column surface, scale, and rectangular micrometer 12 to image recognition system at a preset position.

[0059] An image recognition system is used to analyze and identify image pixels. The industrial camera 9 is connected to the image recognition system and receives the image data transmitted by it. The correspondence between pixels and actual length is determined by the scale on the rectangular micrometer 12. This relationship is then used to analyze the height difference between the liquid column height and the scale of the U-tube manometer 2, identify the height difference of the liquid columns on both sides, and thus measure the small pressure difference in the pipeline.

[0060] As a preferred embodiment of the present invention: the U-tube pressure gauge 2 includes a U-tube, the U-tube being marked with a scale, and both ends of the U-tube having connection ports that are respectively connected to the pipeline system being measured. The pressure on one side of the pipeline is:

[0061] P=ρgh (1)

[0062] In the formula, h is the height of the liquid column on one side of the U-shaped tube, ρ is the density of the working fluid, and g is the acceleration due to gravity.

[0063] The U-tube contains a working fluid, which is one of water, alcohol or mercury. The working fluid in the U-tube is immiscible with the fluid inside the pipeline system being tested, and has stable physical properties and known density. When measuring the micro pressure difference of the pipeline system being tested, both ends of the U-tube are connected to the pipeline system being tested. The pressure difference corresponding to the height difference Δh of the liquid columns on both sides is the micro pressure difference of the pipeline system being tested, using formula (1).

[0064] The screw 6 is connected to the output shaft of the stepper motor 5 via a coupling. The stepper motor 5 is equipped with a power supply and a controller. By controlling the rotation direction, number of rotation steps and rotation speed of the rotor of the stepper motor 5, the position of the motion slide 7 on the screw 6 is changed, thereby changing the position of the camera module 4 so that it can simultaneously include the liquid surface of the U-shaped tube, the scale and the rectangular micrometer 12 in the field of view.

[0065] Limit switches are installed on the upper and lower parts of the screw 6. The limit switches are connected to the controller. When the moving slide 7 moves to the preset position, the limit switch detects the signal and transmits it to the controller. The controller shuts down the stepper motor 5, and the moving slide 7 stops moving.

[0066] The industrial camera 9 is connected to the image recognition system via HDMI. The camera lens 10 is a zoom lens. The horizontal distance between the camera lens 10 and the scale of the U-tube manometer 2 is 7-9 cm.

[0067] The ring light source 11 and the rectangular micrometer 12 are both fixed to the camera bracket 8 by a clamp, and the rectangular micrometer 12 is placed close to the scale of the U-tube pressure gauge 2.

[0068] The smallest division value of the rectangular micrometer 12 is 0.1 mm. By calibrating the pixels corresponding to the smallest division value in the image, the relationship between the physical height and the image pixels can be obtained. This relationship can be used to calculate the pressure corresponding to the height of the liquid column.

[0069] The image recognition system includes a calibration mechanism, an adjustment mechanism, a recognition mechanism, an output mechanism, and a judgment mechanism. The calibration mechanism is used to calibrate the pixels of the received image, where X pixels equal 0.01 mm. The adjustment mechanism is used to adjust the height, movement speed, and direction. The recognition mechanism includes a scale recognition mechanism and a liquid level recognition mechanism. The scale recognition mechanism is used to recognize the scale height and output the scale height H. The liquid level recognition mechanism is used to recognize the pixel corresponding to the difference between the lowest point of the liquid level and the scale height and convert it into a height h. The output mechanism is used to output the liquid level height, where liquid level height H1 = H + h. The judgment mechanism is used to determine whether to measure the liquid level height on both sides. If yes, it directly outputs the pressure value, P = ρ * g * ΔH, where h is the height of the liquid column on one side of the U-shaped tube, ρ is the density of the measured liquid, g is the gravitational acceleration constant, and ΔH = H1 - H2. If no, the height, movement speed, and direction are readjusted through the adjustment mechanism.

[0070] This intelligent micro-pressure measurement system is based on a U-tube manometer 2. It measures pressure by balancing the pressure being measured with the static pressure generated by a liquid column of a certain height, according to the principle of fluid statics. The pressure is converted into the height of the working fluid column, avoiding the use of pressure-sensing elements, ensuring the reliable operation of the device, and achieving the effect of quickly and accurately measuring the micro-pressure of the pipeline system under test.

[0071] Furthermore, this intelligent micro-pressure measuring system can select different working fluids according to actual working conditions, such as water, ethanol, and mercury. After calculating the height of the liquid column, the pressure to be measured can be calculated using conditions such as working fluid density, gravitational acceleration, and reference pressure.

[0072] Furthermore, the camera module 4 includes a high-resolution industrial camera 9, a zoomable camera lens 10, and a ring light source 11. The high-resolution industrial camera 9 has a pixel count ranging from 500w to 2000w. Taking a 2000w pixel lens as an example, it divides the image frame into 5472x3648 grids, with each grid corresponding to one pixel. The higher the pixel count, the higher the recognition of image details.

[0073] Furthermore, camera module 4 includes a zoomable camera lens 10. Camera lens 10 determines the camera's image frame and depth of field. During focusing, only one plane is truly in focus. In a non-focused state, where the object plane is in front of or behind the focusing plane, light emitted from a point on the object at different angles falls onto the image plane, forming a blurred circle called the circle of confusion. If the diameter of the circle of confusion is smaller than the sensor pixel size, this circle of confusion is called the permissible circle of confusion. There is a distance in front of and behind the focusing plane, and the image falls within the permissible range of the circle of confusion; this distance is called the depth of field. In camera module 4, the shooting distance is relatively close (approximately 8cm), and the focal length of camera lens 10 is relatively short (within 50mm). The depth of field of camera lens 10 is controlled within 2mm, which can simultaneously meet the image acquisition requirements of the rectangular micrometer 12, the liquid surface, and the U-tube manometer 2.

[0074] Furthermore, camera module 4 is equipped with a ring light source 11. The industrial camera 9 and camera lens 10 pass through the central notch of the ring light source 11 to capture images. The power of the ring light source 11 and the lens aperture size simultaneously control the image brightness. However, since the aperture size is inversely proportional to the depth of field, the larger the aperture, the shallower the depth of field. In camera module 4, a higher light source brightness and a smaller aperture size are used to avoid the circle of confusion exceeding the sensor pixels, which would result in unclear images and affect sensor accuracy.

[0075] Furthermore, the rectangular micrometer 12 used has a total scale length of 50mm and a minimum division value of 0.1mm. If water is used as the working fluid, according to formula (1), its minimum value is 1Pa. Considering the difference in liquid column height on both sides, the maximum theoretical error after two measurements is 2Pa. The effective length of the U-tube is 500mm, the maximum range is ±5000Pa, and the error range is 0.4%FS. Commonly available micropressure sensors have maximum ranges from 100Pa to 5000Pa, with an error range of 0.5%FS-1%FS. This invention is superior to common similar products on the market in terms of measurement range and accuracy, meeting the requirements for accurate and rapid measurement of micropressure in the tested pipeline system.

[0076] Furthermore, both the rectangular micrometer 12 and the industrial camera module 9 are mounted on the moving slider via a bracket. The up-and-down movement of the slider is controlled by the direction and speed of the rotation of the screw 6, and the relative position of the rectangular micrometer 12 within the field of view of the industrial camera 9 is fixed. During image acquisition, the moving slider is moved up and down to keep the liquid surface of the U-tube within the field of view of the camera lens 10. The relationship between the pixels and the actual height is calibrated using the grid value of the rectangular micrometer 12, thereby determining the height of the liquid column and achieving accurate and rapid measurement of the micropressure of the pipeline system under test.

[0077] Furthermore, to achieve automated and continuous measurement, a stepper motor 5 is installed on the screw 6. The screw 6 and the stepper motor 5 are connected by a coupling. The stepper motor 5 is equipped with a controller and a power supply to control the rotation direction, number of rotation steps and rotation speed of the rotor of the stepper motor 5. This can change the position of the motion slide, thereby changing the position of the camera lens 10, so that the liquid level of the U-tube, the scale and the micrometer can be included in the field of view at the same time.

[0078] Furthermore, limit switches are installed at the top and bottom of the screw 6, and these limit switches are connected to the stepper motor 5 controller. When the moving slide 7 moves to a certain position, the limit switch detects the signal and transmits it to the stepper motor 5 controller, which shuts down the stepper motor 5, thereby stopping the movement of the moving slide 7 and preventing it from colliding and damaging the instrument equipment if it moves beyond the limit.

[0079] Furthermore, the camera module 4 transmits the captured images to the image recognition system in the computer in real time via the HDMI interface. After saving the images, the image analysis system calibrates the pixels corresponding to the smallest grid value of 0.1mm on the rectangular micrometer 12, thereby realizing the conversion between image pixels and the actual object length.

[0080] Furthermore, the image recognition system identifies the pressure gauge scale value closest to the liquid surface and stores this value. Then, by applying the aforementioned conversion relationship between pixels and physical length, it accurately measures the distance from the liquid surface to the nearest scale line and adds it to the stored value to obtain the actual height of the liquid column on one side of the U-tube. This step is repeated on the other side to obtain the height of the liquid column on the other side. The difference between the two values ​​corresponds to the pressure difference, which is the micro-pressure difference of the system under test.

[0081] Furthermore, the entire device is mounted on a frame made of aluminum profiles, which is fixed by corner brackets and screws, ensuring safety, stability, and ease of disassembly and installation.

Claims

1. An intelligent micro-pressure measuring system, characterized in that, include: Aluminum profile frame (1) is used to support and fix the overall structure to form an overall frame; U-tube manometer (2), the U-tube manometer (2) is fixed on the aluminum profile frame (1), the U-tube manometer (2) is connected to the pipeline system to be measured, and the pressure is converted into the height of the liquid column by applying the principle of static pressure and accurately measuring the height of the liquid column, so as to indirectly measure the pipeline micro pressure in the pipeline system to be measured. A lead screw slide (3) with a motor is fixed on an aluminum profile bracket and includes a stepper motor (5) and a lead screw (6). The output shaft of the stepper motor (5) is connected to the lead screw (6). A motion slide (7) is mounted on the lead screw (6). The motion slide (7) is controlled by the stepper motor (5) to move up and down. The camera module (4) includes a camera bracket (8), an industrial camera (9), a camera lens (10), a ring light source (11), a rectangular micrometer (12), and a background plate (13). The motion slide (7) is connected to the camera bracket (8) by bolts. The background plate (13) is fixed to the industrial camera (9) on the camera bracket (8). The camera lens (10), the ring light source (11), and the rectangular micrometer (12) are arranged sequentially between the two. The camera lens (10) is mounted on the industrial camera (9). The ring light source (11) and the rectangular micrometer (12) are fixed on the camera bracket (8) respectively. The camera lens (10) passes through the ring light source (11) and is positioned directly opposite the rectangular micrometer (12). The relative position of the rectangular micrometer (12) in the field of view of the camera lens (10) is fixed. The industrial camera (9) magnifies the images of the liquid column surface, the scale, and the rectangular micrometer (12) at a preset position and transmits them to the image recognition system. The image recognition system is used to analyze and identify image pixels. The industrial camera (9) is connected to the image recognition system and receives the image data transmitted by it. The correspondence between pixels and actual length is determined by the scale on the rectangular micrometer (12). This relationship is then used to analyze the height difference between the liquid column height and the scale of the U-tube manometer (2), identify the height difference of the liquid columns on both sides, and thus measure the small pressure difference in the pipeline.

2. The intelligent micro-pressure measuring system as described in claim 1, characterized in that: The U-tube manometer (2) includes a U-tube with graduations. Both ends of the U-tube have connection ports that are connected to the pipeline system being measured. The pressure on one side of the pipeline is: P=ρgh (1) In the formula, h is the height of the liquid column on one side of the U-shaped tube, ρ is the density of the working fluid, and g is the acceleration due to gravity.

3. The intelligent micro-pressure measuring system as described in claim 2, characterized in that: The U-tube contains a working fluid, which is one of water, alcohol or mercury. The working fluid in the U-tube is immiscible with the fluid inside the pipeline system being tested, and has stable physical properties and known density. When measuring the micro pressure difference of the pipeline system being tested, both ends of the U-tube are connected to the pipeline system being tested. The pressure difference corresponding to the height difference Δh of the liquid columns on both sides is the micro pressure difference of the pipeline system being tested, using formula (1).

4. The intelligent micro-pressure measuring system as described in claim 1, characterized in that: The screw (6) is connected to the output shaft of the stepper motor (5) via a coupling. The stepper motor (5) is equipped with a power supply and a controller. By controlling the rotation direction, number of rotation steps and rotation speed of the rotor of the stepper motor (5), the position of the motion slide (7) on the screw (6) is changed, thereby changing the position of the camera module (4) so ​​that it can simultaneously include the liquid surface of the U-tube, the scale and the rectangular micrometer (12) in the field of view.

5. The intelligent micro-pressure measuring system as described in claim 4, characterized in that: Limit switches are installed on the upper and lower parts of the screw (6). The limit switches are connected to the controller. When the moving slide (7) moves to the preset position, the limit switch detects the signal and transmits it to the controller. The controller shuts down the stepper motor (5) and the moving slide (7) stops moving.

6. The intelligent micro-pressure measuring system as described in claim 1, characterized in that: The industrial camera (9) is connected to the image recognition system via HDMI. The camera lens (10) is a zoom lens. The horizontal distance between the camera lens (10) and the scale of the U-tube manometer (2) is 7-9 cm.

7. The intelligent micro-pressure measuring system as described in claim 1, characterized in that: The ring light source (11) and the rectangular micrometer (12) are both fixed on the camera bracket (8) by a clamp, and the rectangular micrometer (12) is placed close to the scale of the U-tube manometer (2).

8. The intelligent micro-pressure measuring system as described in claim 7, characterized in that: The minimum grid value of the rectangular micrometer (12) is 0.1 mm. By calibrating the pixel corresponding to the minimum grid value in the image, the relationship between the physical height and the image pixels can be obtained. This relationship can be used to calculate the pressure corresponding to the height of the liquid column.

9. The intelligent micro-pressure measuring system as described in claim 1, characterized in that: The image recognition system includes a calibration mechanism, an adjustment mechanism, a recognition mechanism, an output mechanism, and a judgment mechanism. The calibration mechanism is used to calibrate the pixels of the received image, where X pixels equal 0.01 mm. The adjustment mechanism is used to adjust the height, movement speed, and direction. The recognition mechanism includes a scale recognition mechanism and a liquid level recognition mechanism. The scale recognition mechanism is used to recognize the scale height and output the scale height H. The liquid level recognition mechanism is used to recognize the pixel corresponding to the difference between the lowest point of the liquid level and the scale height and convert it into a height h. The output mechanism is used to output the liquid level height, where the liquid level height H1 = H + h. The judgment mechanism is used to determine whether to measure the liquid level height on both sides. If yes, it directly outputs the pressure value, P = ρ * g * ΔH, where h is the height of the liquid column on one side of the U-shaped tube, ρ is the density of the measured liquid, g is the gravitational acceleration constant, and ΔH = H1 - H2. If no, the height, movement speed, and direction are readjusted through the adjustment mechanism.

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