A strain sensor calibration device and method

Abstract

The invention relates to the technical field of metrology and testing, and discloses a strain sensor calibration device and method, comprising a base, a flip piece is arranged on the base, a column is arranged on the flip piece, an equal-strength cantilever beam is arranged on the column, a positioning laser is arranged at one end of the equal-strength cantilever beam away from the column, the ray of the positioning laser is directed toward the base and is parallel to the end face of the equal-strength cantilever beam, and the equal-strength cantilever beam is used for pasting a strain sensor to be measured; a slider is slidably matched on a slide rail, a first pulley is arranged on the slider, a steel wire rope is wound around the first pulley, one end of the steel wire rope is connected to one end of the equal-strength cantilever beam away from the column, and the other end is connected to a force-applying component; a data acquisition module is connected to the strain sensor to be measured and a deflection measurement module, and the data acquisition module is also connected to a host computer. The invention reduces the error caused by stress concentration, effectively improves the consistency and stability of measurement, and improves the flexibility of the device.

Description

Technical Field

[0001] The present invention relates to the technical field of measurement and testing, and in particular to a strain sensor calibration device and method. Background Art

[0002] With the continuous development of engineering technology and materials science, the demand for structural health monitoring and material performance testing is increasing. As an important measurement tool, strain sensors are widely used in bridges, buildings, aerospace and other fields to detect the stress and deformation of structures. However, strain sensors need to be strictly calibrated before use to ensure their measurement accuracy and reliability.

[0003] Traditional strain sensor calibration devices usually use the direct weighting method to generate strain by loading a weight of known weight on the cantilever beam. Although this method is simple, there are some problems in actual operation. First, the direct weighting method is prone to errors in the direction and position of force application, affecting the accuracy of calibration. Second, the traditional device lacks fine adjustment capabilities and cannot adapt to strain sensors of different types and specifications, limiting its scope of application. Summary of the invention

[0004] The object of the present invention is to provide a strain sensor calibration device and method, aiming to solve or improve at least one of the above-mentioned technical problems.

[0005] To achieve the above object, the present invention provides the following solution: The present invention provides a strain sensor calibration device, comprising:

[0006] A base, wherein a flipping piece is arranged on the base, a column is arranged on the flipping piece, the flipping piece is used to adjust the angle between the column and the base, an equal strength cantilever beam is arranged on the column, a positioning laser is arranged at one end of the equal strength cantilever beam away from the column, the ray of the positioning laser is directed toward the base and is parallel to the end face of the equal strength cantilever beam, and the equal strength cantilever beam is used to paste the strain sensor to be measured;

[0007] A slide rail, wherein a slider is slidably matched on the slide rail, a first pulley is arranged on the slider, a steel wire rope is wound around the first pulley, one end of the steel wire rope is connected to one end of the equal-strength cantilever beam away from the column, and the other end is connected to a force-applying component;

[0008] A data acquisition module, wherein the data acquisition module is connected to the strain sensor to be measured, and the data acquisition module is also connected to a host computer;

[0009] A mounting frame is arranged on the column, a deflection measuring module is arranged on the mounting frame, and the deflection measuring module is connected to the data acquisition module.

[0010] Optionally, the deflection measurement module includes a laser displacement sensor, the operating end of the laser displacement sensor faces the equal-strength cantilever beam, and the laser displacement sensor is connected to the data acquisition module.

[0011] Optionally, the deflection measurement module includes a length meter, the working end of the length meter faces one end of the equal-strength cantilever beam close to the positioning laser, and the length meter is connected to the data acquisition module.

[0012] Optionally, the force-applying assembly includes a load plate and a second pulley, the load plate is connected to an end of the steel wire rope away from the equal-strength cantilever beam, the second pulley is arranged on the column, and the steel wire rope is wound around the second pulley.

[0013] Optionally, the slide rail is fixedly connected between the column and the flip member.

[0014] Optionally, the force-applying assembly includes a wire-receiving box, and the wire-receiving box is connected to an end of the steel wire rope away from the equal-strength cantilever beam.

[0015] Optionally, the slide rail is fixedly connected to the base.

[0016] Optionally, a line laser measuring instrument is provided on the base, an operating end of the line laser measuring instrument faces the equal-strength cantilever beam, and the line laser measuring instrument is connected to the data acquisition module.

[0017] Optionally, a standard strain sensor is attached to the equal-strength cantilever beam, and the standard strain sensor is connected to the data acquisition module.

[0018] The present invention also provides a calibration method for a strain sensor, comprising the following steps:

[0019] Step 1, pasting the strain sensor to be measured on the equal-strength cantilever beam, and obtaining the output value of the strain sensor to be measured by the data acquisition module;

[0020] Step 2, pulling the steel wire rope by the force-applying assembly, so that the steel wire rope applies tensile stress to the equal-strength cantilever beam;

[0021] Step 3, sliding the slider and flipping the column to adjust the overlap between the steel wire rope and the ray of the positioning laser;

[0022] Step 4: the data acquisition module obtains the output value of the strain sensor again.

[0023] Step five, repeating step two, step three and step four multiple times to complete the measurement of the strain sensor being measured.

[0024] The present invention discloses the following technical effects:

[0025] By sliding the slider to adjust the force direction of the wire rope and flipping the column to adjust the inclination angle of the equal-strength cantilever beam, a combination of fast coarse adjustment and tiny fine adjustment is achieved to ensure that the direction of force application is always perpendicular to the equal-strength cantilever beam, thereby effectively reducing the measurement error caused by non-vertical application of force and the error caused by stress concentration, effectively improving the consistency and stability of the measurement and enhancing the flexibility of the device.

[0026] The force application method is optimized by the uniform force application method of the force application component, and the micro-strain measurement range of the equal-strength cantilever beam can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0029] Figure 2 This is a structural schematic diagram of Example 2 of the present invention.

[0030] In the figure: 1. base; 2. flip part; 3. column; 4. equal strength cantilever beam; 5. positioning laser; 6. strain sensor to be measured; 7. slide rail; 8. slider; 9. first pulley; 10. wire rope; 11. data acquisition module; 12. host computer; 13. mounting frame; 14. laser displacement sensor; 15. length meter; 16. load plate; 17. second pulley; 18. take-up box; 19. line laser measuring instrument; 20. standard strain sensor; 21. first motor; 22. second motor; 23. third motor. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1, reference Figure 1 , this embodiment provides a strain sensor calibration device, including:

[0034] A base 1, a flip member 2 is arranged on the base 1, a column 3 is arranged on the flip member 2, the flip member 2 is used to adjust the angle between the column 3 and the base 1, an equal strength cantilever beam 4 is arranged on the column 3, a positioning laser 5 is arranged at one end of the equal strength cantilever beam 4 away from the column 3, the ray of the positioning laser 5 is directed toward the base 1 and is parallel to the end face of the equal strength cantilever beam 4, and the equal strength cantilever beam 4 is used to paste the strain sensor 6 to be measured;

[0035] A slide rail 7, a slider 8 is slidably matched on the slide rail 7, a first pulley 9 is arranged on the slider 8, a steel wire rope 10 is wound around the first pulley 9, one end of the steel wire rope 10 is connected to one end of the equal strength cantilever beam 4 away from the column 3, and the other end is connected to a force application component;

[0036] A data acquisition module 11, the data acquisition module 11 is connected to the strain sensor 6 to be measured, and the data acquisition module 11 is also connected to a host computer 12;

[0037] The mounting frame 13 is arranged on the column 3 . A deflection measuring module is arranged on the mounting frame 13 . The deflection measuring module is connected to the data acquisition module 11 .

[0038] To further optimize the solution, the deflection measurement module includes a laser displacement sensor 14, the working end of the laser displacement sensor 14 is facing the equal-strength cantilever beam 4, the laser displacement sensor 14 is connected to the data acquisition module 11, and the laser displacement sensor 14 can be installed at different positions of the mounting frame 13, so as to measure the deflection of the equal-strength cantilever beam 4 at different positions.

[0039] According to a further optimized solution, the deflection measurement module includes a length meter 15 , the working end of the length meter 15 faces one end of the equal-strength cantilever beam 4 close to the positioning laser 5 , and the length meter 15 is connected to the data acquisition module 11 .

[0040] A further optimized solution is that the force-applying assembly includes a load plate 16 and a second pulley 17. The load plate 16 is connected to the end of the wire rope 10 away from the equal-strength cantilever beam 4. The second pulley 17 is arranged on the column 3. The wire rope 10 is wound around the second pulley 17. The slide rail 7 is fixedly connected between the column 3 and the flip member 2. A through hole is opened on the column 3 for the wire rope 10 to pass through.

[0041] Furthermore, the coarse adjustment method of this embodiment is: move the slider 8 so that the steel wire rope 10 on the first pulley 9 is located near the light spot of the positioning laser 5, and fasten the slider 8 to the slide rail 7, so as to quickly adjust the force direction of the steel wire rope 10 to a direction approximately perpendicular to the working end surface of the equal-strength cantilever beam 4;

[0042] Furthermore, the fine adjustment method of this embodiment is: fine adjustment of the pitch of the column 3, so that the outgoing light of the positioning laser 5 is always close to the wire rope 10, thereby ensuring that the wire rope 10 is perpendicular to the working end surface of the equal-strength cantilever beam 4;

[0043] This embodiment also provides a calibration method for a strain sensor, comprising the following steps:

[0044] Step 1: Paste the strain sensor 6 to be measured on the equal strength cantilever beam 4, and use the data acquisition module 11 to obtain the output values ​​of the length meter 15, the laser displacement sensor 14 and the strain sensor 6 to be measured and transmit them to the host computer 12 for display;

[0045] Step 2, the steel wire rope 10 is pulled by the force-applying component, that is, a standard object is added to the load plate 16, and the steel wire rope 10 applies tensile stress to the equal-strength cantilever beam 4;

[0046] Step 3: Slide the slider 8 and flip the column 3 to adjust the coincidence between the steel wire rope 10 and the ray of the positioning laser 5, that is, first make a rough adjustment: move the slider 8 so that the steel wire rope 10 on the first pulley 9 is located near the exit light spot of the positioning laser 5, and fasten the slider 8 to the slide rail 7, so as to quickly adjust the force direction of the steel wire rope 10 to a direction approximately perpendicular to the working end surface of the equal-strength cantilever beam 4;

[0047] Next, fine adjustment is performed: the pitch of the column 3 is finely adjusted so that the outgoing light of the positioning laser 5 is always close to the steel wire rope 10, thereby ensuring that the steel wire rope 10 is perpendicular to the working end surface of the equal-strength cantilever beam 4;

[0048] Step 4: the data acquisition module 11 obtains the output values ​​of the strain sensor 6 , the length meter 15 and the laser displacement sensor 14 again, and sends the data to the host computer 12 .

[0049] Step 5: Repeat steps 2, 3 and 4 multiple times to complete the measurement of the strain sensor 6 to be measured.

[0050] Example 2, reference Figure 2 , this embodiment provides a strain sensor calibration device, including:

[0051] A base 1, a flip member 2 is arranged on the base 1, a column 3 is arranged on the flip member 2, the flip member 2 is used to adjust the angle between the column 3 and the base 1, an equal strength cantilever beam 4 is arranged on the column 3, a positioning laser 5 is arranged at one end of the equal strength cantilever beam 4 away from the column 3, the ray of the positioning laser 5 is directed toward the base 1 and is parallel to the end face of the equal strength cantilever beam 4, and the equal strength cantilever beam 4 is used to paste the strain sensor 6 to be measured;

[0052] A slide rail 7, a slider 8 is slidably matched on the slide rail 7, a first pulley 9 is arranged on the slider 8, a steel wire rope 10 is wound around the first pulley 9, one end of the steel wire rope 10 is connected to one end of the equal strength cantilever beam 4 away from the column 3, and the other end is connected to a force application component;

[0053] A data acquisition module 11, the data acquisition module 11 is connected to the strain sensor 6 to be measured, and the data acquisition module 11 is also connected to a host computer 12;

[0054] The mounting frame 13 is arranged on the column 3 . A deflection measuring module is arranged on the mounting frame 13 . The deflection measuring module is connected to the data acquisition module 11 .

[0055] To further optimize the solution, the deflection measurement module includes a laser displacement sensor 14, the working end of the laser displacement sensor 14 is facing the equal-strength cantilever beam 4, the laser displacement sensor 14 is connected to the data acquisition module 11, and the laser displacement sensor 14 can be installed at different positions of the mounting frame 13, so as to measure the deflection of the equal-strength cantilever beam 4 at different positions.

[0056] According to a further optimized solution, the deflection measurement module includes a length meter 15 , the working end of the length meter 15 faces one end of the equal-strength cantilever beam 4 close to the positioning laser 5 , and the length meter 15 is connected to the data acquisition module 11 .

[0057] According to a further optimized solution, the force-applying assembly includes a wire take-up box 18 , and the wire take-up box 18 is connected to an end of the steel wire rope 10 away from the equal-strength cantilever beam 4 .

[0058] Furthermore, the wire take-up box 18 is connected to a first motor 21 for driving the wire take-up box 18 to reel in the wire rope 10 .

[0059] According to a further optimized solution, the slide rail 7 is fixedly connected to the base 1 .

[0060] Furthermore, a second motor 22 for driving the slider 8 to slide along the slide rail 7 is disposed on the slide rail 7 .

[0061] Furthermore, a third motor 23 is provided on one side of the base 1 for driving the flipping member to drive the column 3 to flip.

[0062] To further optimize the solution, a line laser measuring instrument 19 is provided on the base 1 , the operating end of the line laser measuring instrument 19 faces the equal-strength cantilever beam 4 , and the line laser measuring instrument 19 is connected to the data acquisition module 11 .

[0063] Furthermore, the line laser of the line laser measuring instrument 19 is directed upward to hit the central axis of the equal-strength cantilever beam 4 , and the deflection of each position of the equal-strength cantilever beam 4 can be measured by the line laser measuring instrument 19 .

[0064] According to a further optimized solution, a standard strain sensor 20 is attached to the equal-strength cantilever beam 4 , and the standard strain sensor 20 is connected to the data acquisition module 11 .

[0065] Furthermore, the coarse adjustment method of this embodiment is: move the slider 8 so that the first pulley 9 is located near the light spot of the positioning laser 5, so as to quickly adjust the force direction of the wire rope 10 to a direction approximately perpendicular to the top surface of the equal-strength cantilever beam 4;

[0066] Furthermore, the fine adjustment method of this embodiment is: by finely adjusting the pitch of the column 3, the outgoing light of the positioning laser 5 is always close to the wire rope 10, thereby ensuring that the wire rope 10 is perpendicular to the top surface of the equal-strength cantilever beam 4;

[0067] This embodiment also provides a calibration method for a strain sensor, comprising the following steps:

[0068] Step 1: Paste the strain sensor 6 to be measured on the equal-strength cantilever beam 4, obtain the output values ​​of the strain sensor 6 to be measured and the laser displacement sensor 14 by the data acquisition module 11, and display them on the host computer 12;

[0069] Step 2: The steel wire rope 10 is pulled by the force-applying component, that is, the first motor 21 controls the take-up box 18 to retract a certain length of the steel wire rope 10, and the steel wire rope 10 applies tensile stress to the equal-strength cantilever beam 4;

[0070] Step 3: Slide the slider 8 and flip the column 3 to adjust the overlap between the steel wire rope 10 and the positioning laser 5, that is, first perform a rough adjustment: move the slider 8 so that the first pulley 9 is located near the emission point of the positioning laser 5, so as to quickly adjust the force direction of the steel wire rope 10 to a direction approximately perpendicular to the top surface of the equal-strength cantilever beam 4;

[0071] Next, fine adjustment is performed: by finely adjusting the pitch of the column 3 , the outgoing light of the positioning laser 5 is always kept close to the steel wire rope 10 , thereby ensuring that the steel wire rope 10 is perpendicular to the top end surface of the equal-strength cantilever beam 4 .

[0072] Step 4: the data acquisition module 11 obtains the output values ​​of the laser displacement sensor 14 and the measured strain sensor 6 again, and sends the data to the host computer 12 .

[0073] Step 5: Repeat steps 2, 3 and 4 multiple times to complete the measurement of the strain sensor 6.

[0074] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0075] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A strain sensor calibration device, characterized in that: include: A base (1), wherein a flip member (2) is arranged on the base (1), a column (3) is arranged on the flip member (2), the flip member (2) is used to adjust the angle between the column (3) and the base (1), an equal strength cantilever beam (4) is arranged on the column (3), a positioning laser (5) is arranged at one end of the equal strength cantilever beam (4) away from the column (3), the ray of the positioning laser (5) is directed toward the base (1) and is parallel to the end face of the equal strength cantilever beam (4), and the equal strength cantilever beam (4) is used to paste the strain sensor (6) to be measured; A slide rail (7), wherein a slider (8) is slidably matched on the slide rail (7), a first pulley (9) is arranged on the slider (8), a steel wire rope (10) is wound around the first pulley (9), one end of the steel wire rope (10) is connected to one end of the equal-strength cantilever beam (4) away from the column (3), and the other end is connected to a force-applying component; A data acquisition module (11), the data acquisition module (11) being connected to the measured strain sensor (6), and the data acquisition module (11) being further connected to a host computer (12); A mounting frame (13), wherein the mounting frame (13) is arranged on the column (3), and a deflection measurement module is arranged on the mounting frame (13), and the deflection measurement module is connected to the data acquisition module (11).

2. A strain sensor calibration device according to claim 1, characterized in that: The deflection measurement module comprises a laser displacement sensor (14), the operating end of the laser displacement sensor (14) faces the equal-strength cantilever beam (4), and the laser displacement sensor (14) is connected to the data acquisition module (11).

3. A strain sensor calibration device according to claim 2, characterized in that: The deflection measurement module comprises a length meter (15), the working end of the length meter (15) faces one end of the equal-strength cantilever beam (4) close to the positioning laser (5), and the length meter (15) is connected to the data acquisition module (11).

4. A strain sensor calibration device according to claim 1, characterized in that: The force-applying assembly comprises a load plate (16) and a second pulley (17); the load plate (16) is connected to an end of the steel wire rope (10) away from the equal-strength cantilever beam (4); the second pulley (17) is arranged on the column (3), and the steel wire rope (10) is wound around the second pulley (17).

5. The strain sensor calibration device according to claim 1, characterized in that: The slide rail (7) is fixedly connected between the column (3) and the flip member (2).

6. A strain sensor calibration device according to claim 1, characterized in that: The force-applying assembly comprises a wire take-up box (18), and the wire take-up box (18) is connected to an end of the steel wire rope (10) away from the equal-strength cantilever beam (4).

7. A strain sensor calibration device according to claim 1, characterized in that: The slide rail (7) is fixedly connected to the base (1).

8. The strain sensor calibration device according to claim 1, characterized in that: A line laser measuring instrument (19) is arranged on the base (1), the operating end of the line laser measuring instrument (19) faces the equal-strength cantilever beam (4), and the line laser measuring instrument (19) is connected to the data acquisition module (11).

9. A strain sensor calibration device according to claim 1, characterized in that: A standard strain sensor (20) is attached to the equal-strength cantilever beam (4), and the standard strain sensor (20) is connected to the data acquisition module (11).

10. A calibration method for a strain sensor, based on a strain sensor calibration device according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step 1: Paste the strain sensor (6) to be measured onto the equal-strength cantilever beam (4), and obtain the output value of the strain sensor (6) to be measured by the data acquisition module (11); Step 2: Pulling the steel wire rope (10) through the force-applying component, so that the steel wire rope (10) applies tensile stress to the equal-strength cantilever beam (4); Step three, sliding the slider (8) and flipping the column (3) to adjust the overlap between the steel wire rope (10) and the ray of the positioning laser (5); Step 4: the data acquisition module (11) obtains the output value of the strain sensor (6) again; Step 5, repeating step 2, step 3 and step 4 multiple times to complete the measurement of the strain sensor (6) to be measured.

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