Large deformation displacement sensor and measurement method

Abstract

The present invention discloses a large deformation displacement sensor and a measuring method, which comprises: a housing; a rotatable and translatable displacement steering assembly, which is arranged on the housing; a measuring rope, which is arranged on the displacement steering assembly; a sliding assembly, which is arranged on the housing and connected to the displacement steering assembly; a plurality of deformation beams, which are arranged on the housing; a plurality of springs, one end of which is connected to the sliding assembly and the other end is connected to the deformation beam; and a plurality of detection elements, which are arranged on the deformation beam. The present invention can realize high-precision continuous tracking and monitoring of large structural deformation.

Description

Technical Field

[0001] The present invention relates to the technical field of structural health monitoring, and in particular to a large deformation displacement sensor suitable for slope sliding and structural deformation monitoring, especially high-precision small deformation and large deformation continuous measurement. Background Art

[0002] Deformation and displacement monitoring is an important part of structural safety monitoring and assessment, and is of great significance for ensuring the safe service of engineering structures.

[0003] As my country's transportation infrastructure construction gradually expands to the west, more and more road cutting slopes will appear. Due to the complex geological environment around mountain transportation infrastructure, geological disasters such as landslides and mudslides occur from time to time, becoming the main hidden danger affecting the safe operation of the line. Among them, the deformation of soil slopes before instability is often large, making it difficult for conventional contact displacement sensors to continuously track and monitor, while non-contact displacement sensors are more expensive and have poor real-time performance, which is prone to false alarms and missed reports.

[0004] Therefore, the existing displacement and deformation monitoring technology needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a large deformation displacement sensor and a measurement method for high-precision continuous measurement of small and large deformations, focusing on solving the problem of high-precision continuous monitoring of large deformations of structures.

[0006] The technical solution of the present invention is as follows:

[0007] A large deformation displacement sensor, comprising:

[0008] case;

[0009] A rotatable and translatable displacement steering assembly is disposed on the housing;

[0010] A measuring rope, arranged on the displacement steering assembly;

[0011] A sliding assembly, disposed on the housing and connected to the displacement steering assembly;

[0012] A plurality of deformation beams are arranged on the shell;

[0013] a plurality of springs, one end of which is connected to the sliding assembly and the other end of which is connected to the deformation beam; and

[0014] A plurality of detection elements are arranged on the deformation beam.

[0015] According to a further configuration of the present invention, the displacement steering assembly comprises:

[0016] a rotating drum on which the measuring rope is wound;

[0017] A lead screw is passed through the sliding assembly and the rotating cylinder and is connected to the rotating cylinder;

[0018] A bearing, disposed on the rotating cylinder and connected to the sliding assembly;

[0019] An energy storage spring is arranged between the bearing and the sliding assembly.

[0020] According to a further configuration of the present invention, the surface of the rotating cylinder has a threaded structure, and the measuring rope is wound around the threaded structure; wherein the pitches of the lead screw and the rotating cylinder are equal.

[0021] According to a further configuration of the present invention, the sliding assembly comprises:

[0022] at least one guide rail fixed to the bottom of the housing;

[0023] a bracket, disposed on the guide rail and connected to the bearing; and

[0024] The slider is connected to the guide rail and the bracket respectively.

[0025] According to a further configuration of the present invention, the stiffness of the bracket is greater than the stiffness of the spring.

[0026] According to a further configuration of the present invention, a first side hole is provided on the shell, the measuring rope is passed through the first side hole, and a leading direction of the measuring rope is perpendicular to the axial direction of the rotating cylinder.

[0027] According to a further configuration of the present invention, the first side hole is a tapered hole that increases linearly from the inside to the outside.

[0028] According to a further configuration of the present invention, the large deformation displacement sensor further comprises a tail wire, wherein the tail wire is connected to the detection element; wherein the detection element is an electrical measurement element or a fiber grating measurement element; and a second side hole is provided on the housing, and the tail wire is led out from the second side hole.

[0029] According to a further configuration of the present invention, the large deformation displacement sensor further comprises a plurality of limit portions, wherein the limit portions are arranged on the housing and located on one side of the deformation beam.

[0030] In a further configuration of the present invention, the housing includes first bosses disposed relatively on two sides of the housing, the lead screw is disposed on the first bosses, and the deformation beam is disposed on the first bosses located on one side of the housing;

[0031] The bracket includes a second boss arranged opposite to the bracket, and the bearing is arranged on the second boss.

[0032] Based on the same inventive concept, the present invention also provides a large deformation displacement sensor measurement method, which is applied to the large deformation displacement sensor, and the method comprises the steps of:

[0033] The measuring rope drives the displacement steering assembly to rotate under the traction of the measured object; wherein the number of revolutions of the displacement steering assembly is n:

[0034]

[0035] Where x is the displacement of the object being measured, and R is the winding radius of the displacement steering assembly;

[0036] The displacement steering assembly drives the sliding assembly to move horizontally synchronously; wherein the horizontal displacement of the sliding assembly is ΔL, and the horizontal displacement of the sliding assembly is equal to the horizontal displacement of the displacement steering assembly:

[0037] ΔL = na;

[0038] Where a is the lead of the displacement steering assembly;

[0039] The sliding assembly applies a load to the spring and acts on the deformable beam to cause the deformable beam to bend and deform, wherein the strain of the deformable beam is ε, and the horizontal displacement of the sliding assembly is equal to the deformation of the spring:

[0040] ε=f1(ΔL,k,z);

[0041] Among them, ΔL is the deformation of the spring, k is the spring coefficient, z is the comprehensive coefficient related to the geometric and mechanical parameters of the deformed beam, and f1 is the corresponding mapping relationship;

[0042] The detection element detects the strain generated by the deformed beam and outputs it through the acquisition device, wherein the output Y of the acquisition device is expressed as:

[0043] y=f2(ε); where f2 is the corresponding mapping relationship;

[0044] The relationship between the output of the detection element and the displacement of the measuring rope is established; wherein the displacement steering assembly winding radius R, the displacement steering assembly lead a, the spring coefficient k and the comprehensive coefficient z are given values, and the function f1 and the function f2 are determined mapping relationships. The mapping relationship between the output of the detection element and the displacement of the measuring rope is established according to the mapping relationship between the function f1 and the function f2:

[0045] y=f(x).

[0046] The present invention is further configured such that the detection element is an electrical measuring element or a fiber grating measuring element; if the detection element is an electrical measuring element, the detection element is connected to a collection device and a wireless transmission device respectively; if the detection element is a fiber grating measuring element, a plurality of the detection elements are multiplexed and connected in series to a fiber grating regulator.

[0047] The present invention provides a large deformation displacement sensor and a measurement method, which comprises: a housing; a displacement steering assembly that can rotate and translate, arranged on the housing; a measuring rope, arranged on the displacement steering assembly; a sliding assembly, arranged on the housing and connected to the displacement steering assembly; a plurality of deformation beams, arranged on the housing; a plurality of springs, one end of which is connected to the sliding assembly and the other end is connected to the deformation beam; and a plurality of detection elements, arranged on the deformation beam. The present invention can realize continuous tracking and monitoring of large structural deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary personnel in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0049] Figure 1 It is a structural schematic diagram of the large deformation displacement sensor in the present invention.

[0050] Figure 2 It is a schematic diagram of the local structure of the large deformation displacement sensor in the present invention.

[0051] Figure 3 It is a flow chart of the displacement measurement method in the present invention.

[0052] Figure 4 It is a schematic diagram of the hybrid cantilever beam structure.

[0053] The marks in the accompanying drawings are: 1. Shell; 11. First boss; 12. First side hole; 13. Second side hole; 2. Displacement steering assembly; 21. Rotating cylinder; 22. Screw; 23. Bearing; 24. Energy storage spring; 3. Measuring rope; 4. Sliding assembly; 41. Guide rail; 42. Bracket; 421. Second boss; 43. Sliding block; 5. Detection assembly; 51. Deformation beam; 52. Spring; 53. Detection element; 54. Tail line; 6. Limiting portion. DETAILED DESCRIPTION

[0054] When monitoring large deformations, conventional contact displacement sensors are difficult to track and monitor continuously, while non-contact displacement sensors are costly, have poor real-time performance, and are prone to false alarms and missed alarms. The present invention provides a displacement sensor and a measurement method, and in particular, relates to a large deformation displacement sensor, which is suitable for slope slip and structural deformation monitoring, and is particularly suitable for high-precision continuous tracking and measurement of small and large deformations, solving the problem of high-precision continuous monitoring of large structural deformations. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0055] In the embodiments and patent claims, unless otherwise specified, "a", "an" and "the" may refer to a single or plural number.

[0056] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0057] Please also see Figure 1 to Figure 2 , the present invention provides a preferred embodiment of a large deformation displacement sensor.

[0058] like Figure 1As shown, the present invention provides a large deformation displacement sensor, which includes a housing 1, a displacement steering assembly 2, a measuring rope 3, a sliding assembly 4, and a detection assembly 5. Specifically, the housing 1 is connected to a fixed object, the displacement steering assembly 2 is arranged on the housing 1, the measuring rope 3 is arranged on the displacement steering assembly 2, wherein the displacement steering assembly 2 is rotatable, the measuring rope 3 is wound on the displacement steering assembly 2, and the movable end of the measuring rope 3 passes through the housing 1 and is connected to a measured object, the sliding assembly 4 is arranged on the housing 1 and connected to the displacement steering assembly 2, the detection assembly 5 includes a deformation beam 51, a spring 52, and a detection element 53, the deformation beam 51 is arranged on the housing 1, one end of the spring 52 is connected to the deformation beam 51, and the other end is connected to the sliding assembly 4, the detection element 53 is arranged on the deformation beam 51, and in one embodiment, the spring 52 can be a compression spring. When in use, the measuring rope 3 is pulled by the object to be measured and drives the displacement steering assembly 2 connected to the measuring rope 3 to rotate and translate, thereby driving the sliding assembly 4 to translate toward the direction of the detection assembly 5, so that the spring 52 is deformed and acts on the deformation beam 51 to cause the deformation beam 51 to bend and deform. The detection element 53 can detect the strain generated by the deformation beam 51, so as to obtain the actual displacement change through the detected strain; wherein, the measuring rope 3 is wound around the displacement steering assembly 2, and the displacement steering assembly 2 can realize rotation and translation under the traction of the measuring rope 3, so that the displacement steering assembly 2 realizes a large displacement transformation function, thereby meeting the requirements of large deformation continuous tracking measurement.

[0059] In a further implementation of an embodiment, the displacement steering assembly 2 includes a rotating cylinder 21, a lead screw 22, a bearing 23 and an energy storage spring 24. Specifically, the surface of the rotating cylinder 21 has a threaded structure, and the measuring rope 3 is wound on the threaded structure so that the measuring rope 3 is accurately wound and installed on the rotating cylinder 21. The lead screw 22 is inserted through the sliding assembly 4 and the rotating cylinder 21 and connected to the rotating cylinder 21, wherein a ball nut (not shown in the figure) is provided on the lead screw 22, and the lead screw 22 is fixedly connected to the inside of the rotating cylinder 21 through the ball nut, the bearing 23 is provided on the rotating cylinder 21 and connected to the sliding assembly 4, and the energy storage spring 24 is provided between the bearing 23 and the sliding assembly 4. In an implementation, the energy storage spring 24 can be a spring. The lead screw 22 and the rotating cylinder 21 cooperate to achieve displacement steering to provide a large range and high sensitivity measurement. The lead screw 22 and the rotating cylinder 21 have the same pitch, so as to ensure that the rotating cylinder 21 and the lead screw 22 maintain a synchronous state in the horizontal direction, thereby ensuring the measurement accuracy of the large deformation displacement sensor.

[0060] When the object to be measured pulls the measuring rope, the rotating cylinder 21 rotates and drives the ball nut of the lead screw 22 fixedly connected to the rotating cylinder 21 to translate, thereby driving the sliding assembly 4 to translate synchronously, so that the spring 52 is squeezed and acts on the deformable beam 51 to bend and deform the deformable beam 51, and the detection element 53 can detect the strain generated by the deformable beam 51. While the rotating cylinder 21 rotates, the energy storage spring 24 starts to store energy. When the traction of the measuring rope 3 disappears, the energy storage spring 24 can provide the rotating cylinder 21 with energy for reverse rotation and reciprocating horizontal movement, so that the large deformation displacement sensor has a bidirectional measurement function.

[0061] In a further implementation of an embodiment, a first side hole 12 is provided on the housing 1, the measuring rope 3 is passed through the first side hole 12, and the leading direction of the measuring rope 3 is perpendicular to the axial direction of the rotating cylinder 21, so as to ensure that the starting position of the rotating cylinder 21 and the first side hole 12 are kept on the same cross section. Furthermore, the first side hole 12 is a conical hole that increases linearly from the inside to the outside, so that the measuring rope 3 has a certain ability to change direction on the outside, and ensures that the measuring rope 3 always passes through the first side hole 12 vertically, thereby ensuring the measurement accuracy of the large deformation displacement sensor.

[0062] See also Figure 1 and Figure 2 In a further implementation of an embodiment, the sliding assembly 4 includes two guide rails 41, a bracket 42 and a slider 43. Specifically, the guide rails 41 are relatively arranged on both sides of the bottom of the shell 1, the bracket 42 is arranged on the guide rails 41 and connected to the bearing 23, and the slider 43 is connected to the guide rails 41 and the bracket 42 respectively. Among them, the spring 52 is connected to the bracket 42. When the rotating cylinder 21 rotates, the lead screw 22 drives the bracket 42 connected to the rotating cylinder 21 to slide on the guide rail 41, so that the spring 52 is deformed and acts on the deformation beam 51 to bend and deform the deformation beam 51. When the rotating cylinder 21 rotates in the reverse direction, the lead screw 22 drives the bracket 42 connected to the rotating cylinder 21 to slide in the reverse direction on the guide rail 41, thereby changing the deformation amount of the spring 52.

[0063] It should be noted that the screw 22 and the ball nut, the bearing 23 and the rotating cylinder 21, and the slider 43 and the guide rail 41 cooperate well to reduce the resistance of the overall movement.

[0064] In a further implementation of an embodiment, the large deformation displacement sensor further includes a tail line 54, and the tail line 54 is connected to the detection element 53; wherein the detection element 53 is an electrical measurement element or a fiber grating measurement element; and the housing 1 is provided with a second side hole 13, and the tail line 54 is led out from the second side hole 13. Specifically, the housing 1 is provided with a second side hole 13, and the tail line 54 is led out through the second side hole 13. wherein the detection element 53 can be an electrical measurement element or a fiber grating measurement element, and if the detection element 53 is a fiber grating measurement element, the detection element 53 is installed and arranged on both sides of the deformation beam 51 to form a differential structure, thereby realizing temperature compensation and improving sensitivity, and a plurality of the fiber grating measurement elements are multiplexed and serially connected through the tail line 54 and then connected to a fiber grating demodulator to realize large-scale network monitoring. If the detection element 53 is an electrical measuring element, a temperature measuring element needs to be provided for compensation. The electrical measuring element is connected to the collection device and the wireless transmission device through the tail line 54 to realize remote wireless monitoring.

[0065] Furthermore, the stiffness of the bracket 42 is greater than the stiffness of the spring 52 to ensure that the deformation of one end of the bracket 42 connected to the spring 52 during the measurement process can be ignored, thereby avoiding the occurrence of torsional deformation of the bracket 42 and improving the measurement accuracy.

[0066] It should be noted that the spring 52 and the deformation beam 51 can be provided in plurality, and each spring 52 corresponds to a deformation beam 51, and each spring 52 has a different elastic coefficient, and each deformation beam 51 has different geometric and mechanical parameters, so that the large deformation displacement sensor can achieve measurements of different sensitivities and ranges. In this embodiment, a large deformation displacement sensor having two springs 52 and two deformation beams 51 is used as an example for description.

[0067] In a further implementation of an embodiment, the large deformation displacement sensor further includes a plurality of limit parts 6, which are arranged on the housing 1 and located on one side of the deformation beam 51. Specifically, the limit part 6 is installed on the side of the housing 1, and when the deformation beam 51 is deformed, the large deformation of the deformation beam 51 can be limited, and the large range and small range conversion measurement process have an overload protection function.

[0068] In a further implementation of an embodiment, the housing 1 includes first bosses 11 relatively arranged on both sides of the housing 1, the lead screw 22 is arranged on the first boss 11, and the deformation beam 51 is arranged on the first boss 11 located on one side of the housing 1. The bracket 42 includes a second boss 421 relatively arranged on the bracket 42, and the bearing 23 is arranged on the second boss 421.

[0069] During the specific implementation, that is, during the measurement process, the large deformation displacement sensor is first fixed on a fixed object, and the free end of the measuring rope 3 is connected to the object to be measured. When the object to be measured is displaced relative to the large deformation displacement sensor, the object to be measured will drive the measuring rope 3 to move, and the other end of the measuring rope 3 is wound around the rotating cylinder 21. Therefore, the movement of the object to be measured will drive the rotating cylinder 21 to rotate. The rotating cylinder 21 is connected to the bracket 42 and is fixedly connected to the lead screw 22. The bracket 42 serves as a carrier of the rotating cylinder 21. The rotating cylinder 21 can generate translation through the lead screw 22, and drive the bracket 42 to translate in the same direction, so that the spring 52 connected to the bracket 42 is deformed, and then acts on the deformation beam 51 to bend and deform. The detection element 53 installed on the deformation beam 51 can detect the strain generated by the deformation beam 51, and output the detected data to an external device through the tail line 54 connected to the detection element 53, so as to realize high-precision small deformation and large deformation continuous tracking measurement. During the rotation of the rotating drum 21, the energy storage spring 24 can store energy to provide energy for reverse measurement. The principle of reverse measurement of the large deformation displacement sensor is similar to that of forward measurement, which will not be described in detail here.

[0070] See also Figure 3 Based on the same inventive concept, the present invention also provides a large deformation displacement sensor measurement method, which is applied to the large deformation displacement sensor, and the method comprises the steps of:

[0071] S100, the measuring rope drives the displacement steering assembly to rotate under the traction of the measured object; wherein the number of revolutions of the displacement steering assembly is n:

[0072]

[0073] Where x is the displacement of the object being measured, and R is the winding radius of the displacement steering assembly;

[0074] S200, the displacement steering assembly drives the sliding assembly to move horizontally synchronously; wherein the horizontal displacement of the sliding assembly is ΔL, and the horizontal displacement of the sliding assembly is equal to the horizontal displacement of the displacement steering assembly:

[0075] ΔL = na;

[0076] Where a is the lead of the displacement steering assembly;

[0077] S300, the sliding assembly applies a load to the spring and acts on the deformable beam to cause the deformable beam to bend and deform, wherein the strain of the deformable beam is ε, and the horizontal displacement of the sliding assembly is equal to the deformation of the spring:

[0078] ε=f1(ΔL,k,z);

[0079] Among them, ΔL is the deformation of the spring, k is the spring coefficient, z is the comprehensive coefficient related to the geometric and mechanical parameters of the deformed beam, and f1 is the corresponding mapping relationship;

[0080] S400, the detection element detects the strain generated by the deformed beam and outputs it through a collection device, wherein the output Y of the collection device is expressed as:

[0081] y=f2(ε); where f2 is the corresponding mapping relationship;

[0082] S500, establishing a relationship between the output of the detection element and the displacement of the measuring rope; wherein the displacement steering assembly winding radius R, the displacement steering assembly lead a, the spring coefficient k and the comprehensive coefficient z are given values, and the function f1 and the function f2 are determined mapping relationships, and the mapping relationship between the output of the detection element and the displacement of the measuring rope is established according to the mapping relationship between the function f1 and the function f2:

[0083] y = f(x);

[0084] According to the mapping relationship between the output of the detection element and the displacement of the measuring rope, the input can be obtained by combining the output of the detection element, that is, the measured displacement.

[0085] In a further implementation of an embodiment, the detection element is an electrical measurement element or a fiber grating measurement element. If the detection element is an electrical measurement element, the detection element is connected to a collection device and a wireless transmission device respectively to realize a remote wireless monitoring function. If the detection element is a fiber grating measurement element, a plurality of the detection elements are multiplexed and connected in series to a fiber grating regulator to realize large-scale network monitoring.

[0086] See also Figure 3 and Figure 4 The present invention is further explained by taking the fiber Bragg grating as the detection element and the hybrid cantilever beam as the deformation beam as an example.

[0087] When the hybrid cantilever beam is used as the elastic element, the fiber Bragg grating is pasted on the hybrid cantilever beam, and the traction displacement of the measuring rope causes the displacement steering assembly to rotate and then converts into the horizontal movement of the sliding assembly, and finally acts on the spring to cause the cantilever beam to bend and deform, thereby causing the fiber Bragg grating to produce strain (compression or tension), resulting in a corresponding change in its central wavelength, thereby obtaining the corresponding relationship between the traction displacement and the wavelength change, so that the displacement change can be obtained by measuring the change in the fiber Bragg grating wavelength. Among them, the actual measured displacement of the fiber Bragg grating large deformation displacement sensor is the ratio of the change in the fiber Bragg grating central wavelength to the sensor sensitivity.

[0088] Assuming that the displacement of the measured object is x, the corresponding spring change (that is, the displacement of the bracket along the lead screw) is ΔL, then the number of revolutions of the displacement steering assembly is:

[0089] Then the deformation ΔL of the spring is:

[0090] ΔL=na; wherein a is the lead of the rotating cylinder and the lead screw. The horizontal displacement of the displacement steering assembly and the sliding assembly is equal to the deformation of the spring, both of which are ΔL.

[0091] When the displacement of the measured object causes the internal spring deformation of the fiber Bragg grating large deformation displacement sensor to change, according to Hooke's law, the restoring force of the spring is:

[0092] F=k(ΔL-W B );

[0093] Where k is the elastic coefficient of the spring; ΔL is the change of the spring; w B is the deflection of the hybrid cantilever beam under the action of the spring restoring force.

[0094] The spring force on the hybrid cantilever beam is approximately considered as a concentrated load, and the deflection of the free end of the cantilever beam is:

[0095]

[0096] in,

[0097] Wherein, I is the moment of inertia; E is the elastic modulus of the hybrid cantilever beam; l is the length of the hybrid cantilever beam; l1 is the length of the equal strength section of the hybrid cantilever beam; b0 is the width of the fixed end of the hybrid cantilever beam; b is the width of the free end of the hybrid cantilever beam; and h is the thickness of the hybrid cantilever beam.

[0098] The strain of the equal strength section of the hybrid cantilever beam is:

[0099]

[0100] Where σ is the strain of the hybrid cantilever beam.

[0101] The relationship between the central wavelength of the fiber Bragg grating reflection spectrum and the strain is:

[0102] Where Δλ is the change in the central wavelength of the fiber Bragg grating; λ is the central wavelength of the fiber Bragg grating; P e is the elastic-optical coefficient of the optical fiber material.

[0103] Due to the use of dual fiber Bragg grating differential temperature compensation, the sensitivity of the sensor can be expressed as:

[0104]

[0105] In summary, the present invention provides a large deformation displacement sensor and measurement method, which includes: a housing; a rotatable and translatable displacement steering assembly, which is arranged on the housing; a measuring rope, which is arranged on the displacement steering assembly; a sliding assembly, which is arranged on the housing and connected to the displacement steering assembly; a plurality of deformation beams, which are arranged on the housing; a plurality of springs, one end of which is connected to the sliding assembly and the other end is connected to the deformation beam; and a plurality of detection elements, which are arranged on the deformation beam. The present invention realizes high-precision continuous tracking and monitoring of large structural deformation.

[0106] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A large deformation displacement measurement method, applied to a large deformation displacement sensor, the large deformation displacement sensor comprising a housing; a rotatable and translatable displacement steering assembly, arranged on the housing; a measuring rope, arranged on the displacement steering assembly; a sliding assembly, arranged on the housing and connected to the displacement steering assembly; a plurality of deformation beams, arranged on the housing; a plurality of springs, one end of which is connected to the sliding assembly and the other end is connected to the deformation beam; and a plurality of detection elements, arranged on the deformation beam; characterized in that: The method comprises the steps of: The measuring rope drives the displacement steering assembly to rotate under the traction of the measured object; wherein the number of revolutions of the displacement steering assembly is n: Where x is the displacement of the object being measured, and R is the winding radius of the displacement steering assembly; The displacement steering assembly drives the sliding assembly to move horizontally synchronously; wherein the horizontal displacement of the sliding assembly is ΔL, and the horizontal displacement of the sliding assembly is equal to the horizontal displacement of the displacement steering assembly: ΔL = na; Where a is the lead of the displacement steering assembly; The sliding assembly applies a load to the spring and acts on the deformable beam to cause the deformable beam to bend and deform, wherein the strain of the deformable beam is ε, and the horizontal displacement of the sliding assembly is equal to the deformation of the spring: ε=f1(ΔL,k,z); Among them, ΔL is the deformation of the spring, k is the spring coefficient, z is the comprehensive coefficient related to the geometric and mechanical parameters of the deformed beam, and f1 is the corresponding mapping relationship; The detection element detects the strain generated by the deformed beam and outputs it through the acquisition device, wherein the output Y of the acquisition device is expressed as: y=f2(ε); where f2 is the corresponding mapping relationship; The relationship between the output of the detection element and the displacement of the measuring rope is established; wherein the displacement steering assembly winding radius R, the displacement steering assembly lead a, the spring coefficient k and the comprehensive coefficient z are given values, and the function f1 and the function f2 are determined mapping relationships. The mapping relationship between the output of the detection element and the displacement of the measuring rope is established according to the mapping relationship between the function f1 and the function f2: y=f(x).

2. The large deformation displacement measurement method according to claim 1, characterized in that: The displacement steering assembly comprises: a rotating drum on which the measuring rope is wound; A lead screw is passed through the sliding assembly and the rotating cylinder and is connected to the rotating cylinder; A bearing, disposed on the rotating cylinder and connected to the sliding assembly; An energy storage spring is arranged between the bearing and the sliding assembly.

3. The large deformation displacement measurement method according to claim 2, characterized in that: The surface of the rotating cylinder has a thread structure, and the measuring rope is wound around the thread structure; wherein the pitch of the lead screw and the rotating cylinder are equal.

4. The large deformation displacement measurement method according to claim 2, characterized in that: The sliding assembly comprises: at least one guide rail fixed to the bottom of the housing; A bracket, arranged on the guide rail and connected to the bearing; wherein the stiffness of the bracket is greater than the stiffness of the spring; And a sliding block is connected to the guide rail and the bracket respectively.

5. The large deformation displacement measurement method according to claim 2, characterized in that: The shell is provided with a first side hole, the measuring rope is passed through the first side hole, and the leading direction of the measuring rope is perpendicular to the axial direction of the rotating cylinder; wherein the first side hole is a conical hole which increases linearly from the inside to the outside.

6. The large deformation displacement measurement method according to claim 1, characterized in that: The large deformation displacement sensor further comprises a tail wire, which is connected to the detection element; wherein the detection element is an electrical measurement element or a fiber grating measurement element; a second side hole is provided on the housing, and the tail wire is led out from the second side hole.

7. The large deformation displacement measurement method according to claim 1, characterized in that: The large deformation displacement sensor further includes a plurality of limit parts, which are arranged on the housing and located on one side of the deformation beam.

8. The large deformation displacement measurement method according to claim 4, characterized in that: The housing comprises first bosses arranged opposite to each other on two sides of the housing, the lead screw is arranged on the first bosses, and the deformation beam is arranged on the first bosses located on one side of the housing; The bracket includes a second boss arranged opposite to the bracket, and the bearing is arranged on the second boss.

9. The large deformation displacement measurement method according to claim 6, characterized in that: If the detection element is an electrical measuring element, the detection element is connected to the acquisition device and the wireless transmission device respectively; if the detection element is a fiber grating measuring element, a plurality of the detection elements are multiplexed and connected in series to the fiber grating regulator.

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