A fiber grating vibration sensor and detection system for garage status detection

Abstract

The present invention belongs to the field of fiber grating sensing technology, and provides a fiber grating vibration sensor and detection system for garage status detection, which aims to solve the problem that the common multi-dimensional fiber grating vibration sensor is large in size. In addition, the composite beam with a special structure solves the spectral chirp phenomenon caused by uneven strain of the traditional cantilever beam structure FBG, and solves the problem that the fiber suspension structure used in the current multi-dimensional FBG is prone to breakage of the fiber, and retains the high sensitivity and temperature compensation characteristics of the FBG in the symmetrical structure. By judging the vibration frequency of the carrier in different directions, it can be inferred whether the garage is in a normal working state, thereby improving the detection accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of optical fiber grating sensing, and in particular relates to an optical fiber grating vibration sensor for garage state detection. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, fiber gratings are mostly used for garage status detection. Fiber Bragg Gratings (FBG) sensors have the characteristics of anti-electromagnetic interference, high sensitivity, wide dynamic measurement range, and the ability to work in harsh environments for a long time. Their application range is becoming increasingly wide.

[0004] Since there is a linear relationship between the displacement of the center wavelength of the fiber Bragg grating and the acceleration of the external object being measured, the magnitude of the vibration acceleration can be obtained by demodulating the change in the center wavelength of the FBG. Therefore, the FBG vibration sensor can actually be understood as an FBG acceleration sensor. By using the fiber Bragg grating sensing principle and the principle of structural dynamics, and using the structural response system, the vibration signal is picked up through the wavelength change of the fiber Bragg grating. There are three main structures designed for fiber Bragg grating vibration sensors: cantilever beam structure, core shaft structure, horizontal fiber Bragg grating structure, etc.

[0005] Research on the FBG vibration sensors of the above three structures focuses more on how to improve the sensitivity and natural frequency of the sensors, especially the cantilever beam vibration sensor. Various improvements to the beam structure have become an effective means to improve the performance of the sensor. However, in the current application of detecting whether the garage is in normal working condition, although the measurement performance has been greatly improved, the single-component FBG vibration sensor will be subject to many limitations in practical applications, so the multi-component FBG vibration sensor has become a hot topic of current research. Due to the need to measure vibrations in multiple directions, the current multi-component sensors are generally large in size and inconvenient to use. Summary of the invention

[0006] In order to solve at least one technical problem existing in the above-mentioned background technology, a first aspect of the present invention provides a fiber grating vibration sensor for garage status detection, which realizes the miniaturization of the sensor while ensuring the measurement accuracy and sensitivity of the garage status.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A fiber grating vibration sensor for garage status detection includes a T-beam, an L-beam, a mass block and a fiber grating arranged in a protective shell;

[0009] The T-shaped beam is fixed to the inner wall of the protective shell, and includes a crossbeam with a central symmetrical structure and a vertical cantilever beam located at the geometric center of the crossbeam, and a mass block is fixed at the lower end of the vertical cantilever beam;

[0010] L-shaped beams are arranged below the left and right sides of the crossbeam, and the L-shaped beams include a horizontal beam and an oblique beam. One end of the horizontal beam is fixed to the inner wall of the protective shell, and the other end is connected to one end of the oblique beam. The other end of the oblique beam is fixed to the lower end of the crossbeam. A transverse connecting beam is arranged between the L-shaped beams on the same side, and the connecting beams are respectively connected to the horizontal beams on this side. A first group of fiber gratings are arranged on the horizontal symmetry axes of the upper and lower surfaces of the crossbeam to measure the vibration signal in the z-axis direction, a second group of fiber gratings are arranged at the front and rear vertical symmetry axes of the vertical cantilever beam to measure the vibration signal in the y-axis direction, and a third group of fiber gratings are arranged on the connecting beams on both sides to measure the vibration signal in the x-axis direction. Each group of fiber gratings is subjected to stress in opposite directions, thereby generating opposite strains.

[0011] As an embodiment, the protective shell is provided with a first optical fiber through hole and a second optical fiber through hole, and the first optical fiber through hole and the second optical fiber through hole are both provided with a protective tube and a base, and the base is provided in the protective tube for fixing the optical fiber, and one end of the optical fiber enters through the first protective tube and the first base, is led out through the second protective tube and the second base, and is connected to the optical fiber demodulator.

[0012] As an embodiment, a middle circular hole, a left circular hole and a right circular hole are set on the crossbeam, and the centers of the three circular holes are all on a horizontal line. The diameter of the middle circular hole is larger than the diameters of the left circular hole and the right circular hole, and the diameters of the left circular hole and the right circular hole are equal.

[0013] As an implementation manner, the diameter range of the middle circular hole is: 20-35mm, and the diameter range of the left circular hole and the right circular hole is: 4-7mm.

[0014] As an embodiment, the crossbeam includes two identical "rectangle-isosceles trapezoid-rectangle" structures, and the two structures are a whole, wherein the base of each isosceles trapezoid is equal to the width of the rectangle close to the inner wall of the protective shell, the width of the rectangle on this side is greater than its length, and the top of the isosceles trapezoid is equal to the width of the rectangle away from the inner wall of the protective shell, and the width of the rectangle on this side is equal to the length.

[0015] As an implementation mode, the vertical cantilever beam is arranged in a quasi-isosceles trapezoid-rectangle-triangle structure from top to bottom, and a semicircular hole is opened in the quasi-isosceles trapezoid.

[0016] As an implementation mode, the included angle between the horizontal beam and the inclined beam is 120°.

[0017] As an implementation, optical fiber fixing points are provided between a set of L-shaped beams located on one side.

[0018] As an implementation manner, the first group of fiber gratings includes fiber grating No. 1 and fiber grating No. 6, the first group of fiber gratings includes fiber grating No. 2 and fiber grating No. 3, and the third group of fiber gratings includes fiber grating No. 4 and fiber grating No. 5;

[0019] Among them, fiber grating No. 1 is fixed on the horizontal symmetry axis on the left side panel of the platform beam; fiber grating No. 2 is fixed on the vertical symmetry axis position of the vertical cantilever beam, fiber grating No. 3 is fixed on the back of fiber grating No. 2, fiber grating No. 4 is fixed on the connecting beam, and the optical fibers on the left and right sides of the fiber grating are respectively fixed on the first horizontal beam and the second horizontal beam, fiber grating No. 5 is fixed opposite to fiber grating No. 4, and fiber grating No. 6 is fixed on the horizontal symmetry axis of the lower surface of the right side panel of the platform beam, and the horizontal distance from the right protective shell is the same as the horizontal distance from fiber grating No. 1 to the left protective shell.

[0020] A second aspect of the present invention provides a fiber grating vibration sensor for garage state detection, which realizes the miniaturization of the sensor while ensuring the measurement accuracy and sensitivity of the garage state.

[0021] In order to achieve the above object, the present invention adopts the following technical solution:

[0022] A garage state detection system comprises the fiber grating vibration sensor and a processor as described in the first aspect, wherein the processor is configured to: receive multi-dimensional measurement data acquired by the vibration sensor, demodulate the data through a demodulator, analyze the structural damage in different directions of a carrier carrying a vehicle in a lifting stereo garage, and obtain the working state of the garage;

[0023] If the data obtained by the demodulator does not have continuous and obvious fluctuations, the working status of the garage is normal;

[0024] If the data demodulated by the demodulator shows long-term continuous vibration in one or more dimensions, it indicates that the garage infrastructure has structural damage and further investigation is required.

[0025] The beneficial effects of the present invention are:

[0026] In view of the large size of the common multi-dimensional fiber Bragg grating vibration sensor, the composite beam with a special structure not only solves the spectral chirp phenomenon caused by uneven strain of the traditional cantilever beam structure FBG, but also solves the problem that the fiber suspension structure used in the current multi-dimensional FBG is prone to breakage of the fiber. It also retains the high sensitivity and temperature compensation characteristics of the FBG in the symmetrical structure. By judging the vibration frequency of the carrier in different directions, it can be inferred whether the garage is in normal working condition, thereby improving the detection accuracy.

[0027] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0029] Figure 1 is a front cross-sectional view of a multi-dimensional fiber grating vibration sensor for garage status detection provided by this embodiment;

[0030] Figure 2 is a left sectional view of a multi-dimensional fiber Bragg grating vibration sensor for garage status detection provided by this embodiment;

[0031] Figure 3 is a top cross-sectional view of a multi-dimensional fiber grating vibration sensor for garage status detection provided by this embodiment;

[0032] Figure 4 is a front view of a T-beam provided in this embodiment;

[0033] Figure 5 is a top view of a T-beam provided in this embodiment;

[0034] Figure 6 is a front view of an L-shaped beam provided in this embodiment;

[0035] Figure 7 is a left view of the L-shaped beam provided in this embodiment;

[0036] Figure 8 This is a schematic diagram of L-shaped beam optical fiber pasting provided in this embodiment;

[0037] Fig. 9 This is the FBG pasting schematic diagram provided in this embodiment. Figure 1 ;

[0038] Fig.10 This is the FBG pasting schematic diagram provided in this embodiment. Figure 2 ;

[0039] Fig.11 is a layout diagram of the fiber Bragg grating vibration sensor provided in this embodiment for state detection;

[0040] Among them, 1. protective shell, 2. protective tube, 21. first protective tube, 22. second protective tube, 3. base, 31. first base, 32. second base, 4. T-beam, 41. crossbeam, 42. vertical cantilever beam, 43. semicircular hole, 44. left circular hole, 45. middle circular hole, 46. right circular hole, 5. L-beam, 51. horizontal beam, 511. first horizontal beam, 512. second horizontal beam, 52. oblique beam, 521. first oblique beam, 522. second oblique beam, 6. fiber Bragg grating, 61. first fiber Bragg grating, 6 2. Fiber Bragg grating No. 2, 63. Fiber Bragg grating No. 3, 64. Fiber Bragg grating No. 4, 65. Fiber Bragg grating No. 5, 66. Fiber Bragg grating No. 6, 7. Mass block, 8. Connecting beam, 9. Optical fiber, 91. First optical fiber fixing point, 92. Second optical fiber fixing point, 10. Fiber Bragg grating vibration sensor, 101. Fiber Bragg grating vibration sensor No. 1, 102. Fiber Bragg grating vibration sensor No. 2, 103. Fiber Bragg grating vibration sensor No. 3, 104. Fiber Bragg grating vibration sensor No. 4, 11. Carriage plate, 12. Fiber lead-out end. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0042] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0043] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0044] In the present invention, terms such as "upper", "lower", "left", "right", "rear", "vertical", "horizontal" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present invention, and do not specifically refer to any part or element in the present invention and should not be understood as limitations on the present invention.

[0045] In the present invention, terms such as "connected" and "connection" should be understood in a broad sense, indicating that the connection can be fixed, integral or detachable; it can be directly connected or indirectly connected through an intermediate medium. Relevant scientific research or technical personnel in this field can determine the specific meaning of the above terms in the present invention according to specific circumstances, and they should not be understood as limiting the present invention.

[0046] Embodiment 1

[0047] See also Figure 1-Figure 11 , this embodiment provides a fiber Bragg grating vibration sensor for garage status detection, comprising a T-beam 4, an L-beam 5, a fiber Bragg grating 6 and a mass block 7 arranged in a protective shell 1;

[0048] Taking the vehicles parked in the garage in compliance with the safe parking specifications as a reference, the garage coordinate axes are calibrated as follows:

[0049] The geometric center of the garage car loading plate 11 is the coordinate origin, the front of the car is facing the positive direction of the x-axis, the driving side of the vehicle (left-hand drive) is facing outwards as the positive direction of the y-axis, and the direction perpendicular to the car loading plate toward the roof is the positive direction of the z-axis.

[0050] Taking the No. 2 fiber Bragg grating vibration sensor 102 as an example, the directions of measurement of each group of FBGs of the sensor are as follows:

[0051] Among them, the first group of fiber Bragg gratings (fiber Bragg grating No. 1 and fiber Bragg grating No. 6) measures the vibration signal in the z-axis direction; the second group of fiber Bragg gratings (fiber Bragg grating No. 2 and fiber Bragg grating No. 3) measures the vibration signal in the y-axis direction, and the third group of fiber Bragg gratings (fiber Bragg grating No. 4 and fiber Bragg grating No. 5) measures the vibration signal in the x-axis direction.

[0052] The T-beam 4 is fixed to the inner wall of the protective shell 1, and includes a crossbeam 41 with a central symmetrical structure and a vertical cantilever beam 42 located at the geometric center of the crossbeam, and a mass block 7 is fixed at the lower end of the vertical cantilever beam 42;

[0053] An L-shaped beam 5 is arranged below the left and right sides of the crossbeam 41, and the L-shaped beam 5 includes a horizontal beam 51 and an oblique beam 52. One end of the horizontal beam 51 is fixed to the inner wall of the protective shell 1, and the other end is connected to one end of the oblique beam 52. The other end of the oblique beam 52 is fixed to the lower end of the crossbeam 41. A transverse connecting beam 8 is arranged between the L-shaped beams 5 on the same side, and the connecting beams 8 are respectively connected to the horizontal beam 51 on this side. A first group of fiber gratings is arranged on the horizontal symmetry axis of the upper surface and the lower surface of the crossbeam 41, a second group of fiber gratings is arranged at the front and rear vertical symmetry axis positions of the vertical cantilever beam, and a third group of fiber gratings is arranged on the connecting beams on both sides, and each group of fiber gratings is subjected to stress in opposite directions, thereby generating opposite strains.

[0054] Through the technical solution of the T-shaped beam and multiple L-shaped beams with a combined beam structure, this combination greatly improves the volume utilization of the sensor and solves the problem of the large volume of the multi-dimensional fiber Bragg grating vibration sensor currently common on the market. In addition, the use of a composite beam with a special structure not only solves the spectral chirp phenomenon caused by uneven strain of the traditional cantilever beam structure FBG, but also solves the problem that the fiber suspension structure used in the current multi-dimensional FBG is prone to breakage of the fiber, and retains the high sensitivity and temperature compensation characteristics of the FBG in the symmetrical structure.

[0055] like Figure 2-Figure 3 As shown, the protective shell 1 is provided with a first optical fiber through hole and a second optical fiber through hole, and the first optical fiber through hole and the second optical fiber through hole are both provided with a protective tube 2 and a base 3. The base 3 is arranged in the protective tube 2 for fixing the optical fiber, and one end of the optical fiber enters through the first protective tube 21 and the first base 31, and is led out through the second protective tube 22 and the second base 32 and then connected to the optical fiber demodulator.

[0056] like Fig.11 As shown, in this embodiment, four fiber Bragg grating vibration sensors are used to measure the vibration of the garage. The optical fiber is introduced from the fourth fiber Bragg grating vibration sensor 104, the fiber lead-out end 12 is connected to the fiber demodulator, and the other end is fixed to the first base 31 of the third fiber Bragg grating vibration sensor.

[0057] like Figure 4 As shown, the T-shaped beam 4 is arranged in a "T"-shaped structure, and the main body includes two parts, a cross beam 41 and a vertical cantilever beam 42 perpendicular to the cross beam 41;

[0058] like Figure 5 As shown, the crossbeam 41 is provided with a middle circular hole 45, a left circular hole 44 and a right circular hole 46, the centers of which are all on a horizontal line, and the left circular hole 44 and the right circular hole 46 allow the optical fiber to pass freely.

[0059] The crossbeam 41 is of a centrally symmetrical structure, with the center of symmetry being the center of the middle circular hole 45 , and all points on the entire top being symmetrical points. The middle circular hole 42 mainly serves to allow the optical fiber 10 to pass through and reduce the weight of the beam, and has a relatively large diameter.

[0060] In this embodiment, the diameter of the middle circular hole 45 is much larger than the diameters of the left circular hole 44 and the right circular hole 46, and the diameters of the left circular hole 44 and the right circular hole 46 are equal;

[0061] In this embodiment, the diameter range of the middle circular hole 45 is: 20-35mm;

[0062] The diameter range of the left circular hole 44 and the right circular hole 46 is 4-7 mm.

[0063] like Figure 5 As shown, in this embodiment, the beam 41 includes two identical "rectangle-isosceles trapezoid-rectangle" structures, and the two structures are a whole, wherein the base of each isosceles trapezoid is equal to the width of the rectangle close to the inner wall side of the protective shell, and the width of the rectangle on this side is greater than its length.

[0064] The isosceles trapezoidal structure can make the FBG pasting point be subjected to uniform stress, thus avoiding the spectral chirp phenomenon caused by non-uniform stress.

[0065] A simple isosceles rectangular structure has poor stability. Using a rectangular structure at the vibration point of the beam structure can make the cantilever beam more stable. The upper side of the isosceles trapezoid is equal to the width of the rectangle away from the inner wall of the protective shell, and the width of the rectangle is equal to the length.

[0066] in, Figure 4 In the figure, the vertical cantilever beam 42 is arranged in a "quasi-isosceles trapezoid-rectangle-triangle" structure from top to bottom, and a semicircular hole is opened in the quasi-isosceles trapezoid. This part of the structure is based on the structure of the horizontal beam 41, and a rounded shape is added at the connection to increase the stability of the connection.

[0067] The entire T-beam 4 presents a strictly symmetrical structure, and its function is to produce different wavelength drifts by subjecting the FBGs pasted at corresponding positions to stresses in opposite directions. According to the fiber coupling mode theory, this design method can eliminate the influence of temperature on wavelength drift, and at the same time can expand the sensitivity of the sensor to twice that of a single FBG.

[0068] like Figure 6 As shown, the L-shaped beam 5 includes a horizontal beam 51 and an oblique beam 52 , and the angle between the horizontal beam and the oblique beam 52 is 120°. There are four groups in total, with two on each side below the left and right sides of the cross beam 41 .

[0069] like Figure 7-Figure 8 As shown, the horizontal beam 51 includes a first horizontal beam 511 and a second horizontal beam 512, and the inclined beam 52 includes a first inclined beam 521 and a second inclined beam 522; there is a transverse connecting beam 8 in the middle of the two L-shaped beams 5 on the same side, and the left and right sides of the connecting beam 8 are respectively connected to the first horizontal beam 511 of the left L-shaped beam structure and the second horizontal beam 512 of the right L-shaped beam structure.

[0070] The combination of the four L-shaped beams can support the platform cross beam 41 of the T-shaped beam 4 .

[0071] In this embodiment, the structure of the connecting beam 8 is the same as that of the cross beam 41 .

[0072] like Figure 8As shown, at the same time, an optical fiber fixing point is added between a group of L-shaped beams located on one side, the first optical fiber fixing point 91 and the second optical fiber fixing point 92. This structure makes full use of the effective space of the sensor. In addition, the vibration beams in three directions that are staggered with each other can play a role of restraining each other: that is, the up and down vibration of the platform beam 41 will be restrained by the four L-shaped beams 5, thereby reducing the impact on the vertical cantilever beam 42; the front and back vibration of the vertical cantilever beam 42 will be restrained by the platform beam 42, thereby reducing the impact on the connecting beam 8; the left and right vibration of the connecting beam 8 will be affected by the entire T-shaped beam 4 structure, thereby reducing the impact on the platform beam 41 and the vertical cantilever beam 42.

[0073] like Figure 9-10 As shown, there are 6 groups of fiber Bragg gratings 6, namely, a first fiber Bragg grating 61, a second fiber Bragg grating 62, a third fiber Bragg grating 63, a fourth fiber Bragg grating 64, a fifth fiber Bragg grating 65, and a sixth fiber Bragg grating 66.

[0074] The optical fiber is fixed on the rear base 3 through the optical fiber protection tube 2. After the optical fiber enters, the first optical fiber grating 61 is fixed on the horizontal symmetry axis on the left side panel of the crossbeam 41;

[0075] The second fiber Bragg grating 62 is fixed on the vertical symmetry axis of the vertical cantilever beam 42, the third fiber Bragg grating 63 is fixed on the back of the second fiber Bragg grating 62, the fourth fiber Bragg grating 64 is fixed on the connecting beam 8, and the optical fibers on the left and right sides of the fiber Bragg grating are respectively fixed on the horizontal beam 51 of the left L-shaped beam structure and the horizontal beam 52 of the right L-shaped beam structure.

[0076] The fifth fiber grating 65 is fixed opposite to the fourth fiber grating 64, and the method of fixing the optical fiber is the same as that of the fourth fiber grating 64. The sixth fiber grating 66 is fixed on the horizontal symmetry axis of the lower surface of the right side panel of the platform crossbeam 41, and the horizontal distance from the right side protective shell 1 is the same as the horizontal distance from the first fiber grating 61 to the left side protective shell 1.

[0077] The six FBGs can be divided into three groups, where the first fiber Bragg grating 61 and the sixth fiber Bragg grating 66 form a group, the second fiber Bragg grating 62 and the third fiber Bragg grating 63 form a group, and the fourth fiber Bragg grating 64 and the fifth fiber Bragg grating 65 form a group. Each group of fiber Bragg gratings will be subjected to stress in opposite directions, thereby generating opposite strains.

[0078] Since the same group of fiber Bragg gratings are affected by temperature in the same way (the internal ambient temperature of the sensor is similar), according to the fiber coupled mode theory, the difference method can be used to eliminate the influence of temperature on the central wavelength of FBG reflection within the same group. At the same time, the sensitivity of the sensor can be increased to twice the original level.

[0079] The working principle of the present invention is:

[0080] Taking the second fiber grating vibration sensor 102 as an example, when the object under test vibrates, each group of FBGs has different sensitivities to different directions due to the special beam structure design of the sensor, which will produce different measurement results.

[0081] The first group of fiber Bragg gratings mainly depends on the deformation of the cross beam 41 to change the FBG central wavelength, and the T-beam 4 is more sensitive to the vibration signal in the z-axis direction and is hardly affected by the x- and y-axis directions. Therefore, the first group of fiber Bragg gratings is used to measure the vibration signal in the z-axis direction.

[0082] The second group of fiber Bragg gratings mainly depends on the deformation of the vertical cantilever beam 42 to change the FBG central wavelength. The vertical cantilever beam 42 is more sensitive to the vibration signal in the y-axis direction and is hardly affected by the x- and z-axis directions. Therefore, the second group of fiber Bragg gratings is used to measure the vibration signal in the y-axis direction.

[0083] The third group of fiber Bragg gratings mainly relies on the deformation of the connecting beam 8 to change the FBG central wavelength. The connecting beam 8 is more sensitive to the vibration signal in the x-axis direction and is hardly affected by the y and z-axis directions. Therefore, the third group of fiber Bragg gratings is used to measure the vibration signal in the x-axis direction.

[0084] The three-dimensional fiber Bragg grating vibration sensor with a combined beam structure can be used in situations where multi-dimensional measurement of structural vibration is required. For example, the carriers carrying vehicles in a liftable multi-story garage need to constantly detect structural damage in different directions. By judging the vibration frequency of the carriers in different directions, it can be inferred whether the garage is in normal working condition.

[0085] Embodiment 2

[0086] This embodiment provides a garage state detection system, including the vibration sensor and processor described in the first embodiment, wherein the processor is configured to: receive multi-dimensional measurement data acquired by the vibration sensor, demodulate the data through a demodulator, analyze the structural damage of a vehicle carrier in a lifting stereo garage in different directions, and obtain the working state of the garage;

[0087] If the data obtained by the demodulator does not have continuous and obvious fluctuations, the working status of the garage is normal;

[0088] If the data demodulated by the demodulator shows long-term continuous vibration in one or more dimensions, it indicates that the garage infrastructure has structural damage and further manual inspection is required.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A fiber grating vibration sensor for garage status detection, characterized in that: It includes a T-beam, an L-beam, a mass block and a fiber grating arranged in a protective shell; The T-shaped beam is fixed to the inner wall of the protective shell, and includes a crossbeam with a central symmetrical structure and a vertical cantilever beam located at the geometric center of the crossbeam, and a mass block is fixed at the lower end of the vertical cantilever beam; L-shaped beams are arranged below the left and right sides of the crossbeam, and the L-shaped beams include horizontal beams and oblique beams. There are four groups of horizontal beams and oblique beams, two of which are arranged below the left and right sides of the crossbeam, one end of the horizontal beam is fixed to the inner wall of the protective shell, and the other end is connected to one end of the oblique beam, and the other end of the oblique beam is fixed to the lower end of the crossbeam. A transverse connecting beam is arranged between the L-shaped beams on the same side, and the connecting beams are respectively connected to the horizontal beams on this side. A first group of fiber gratings is arranged on the horizontal symmetry axes of the upper and lower surfaces of the crossbeam to measure the vibration signal in the z-axis direction, a second group of fiber gratings is arranged on the front and rear vertical symmetry axes of the vertical cantilever beam to measure the vibration signal in the y-axis direction, and a third group of fiber gratings is arranged on the connecting beams on both sides to measure the vibration signal in the x-axis direction, and each group of fiber gratings is subjected to stress in opposite directions, thereby generating opposite strains; Among them, the horizontal beam includes a first horizontal beam and a second horizontal beam, and the inclined beam includes a first inclined beam and a second inclined beam; there is a transverse connecting beam in the middle of the two L-shaped beams on the same side, and the left and right sides of the connecting beam are respectively connected to the first horizontal beam of the left L-shaped beam structure and the second horizontal beam of the right L-shaped beam structure.

2. A fiber grating vibration sensor for garage status detection as claimed in claim 1, characterized in that: The protective shell is provided with a first optical fiber through hole and a second optical fiber through hole, and both the first optical fiber through hole and the second optical fiber through hole are provided with a protective tube and a base, and the base is arranged in the protective tube for fixing the optical fiber, and one end of the optical fiber enters through the first protective tube and the first base, is led out through the second protective tube and the second base, and is connected to the optical fiber demodulator.

3. The fiber grating vibration sensor for garage status detection according to claim 1, characterized in that: The crossbeam is provided with a middle circular hole, a left circular hole and a right circular hole, the centers of which are all on a horizontal line, the diameter of the middle circular hole is larger than the diameters of the left circular hole and the right circular hole, and the diameters of the left circular hole and the right circular hole are equal.

4. A fiber grating vibration sensor for garage status detection as claimed in claim 3, characterized in that: The diameter range of the middle circular hole is: 20-35mm, and the diameter range of the left circular hole and the right circular hole is: 4-7mm.

5. The fiber grating vibration sensor for garage status detection according to claim 1, characterized in that: The crossbeam includes two identical "rectangle-isosceles trapezoid-rectangle" structures, and the two structures are integrated, wherein the bottom side of each isosceles trapezoid is equal to the width of the rectangle close to the inner wall of the protective shell, and the width of the rectangle on this side is greater than its length, and the top side of the isosceles trapezoid is equal to the width of the rectangle away from the inner wall of the protective shell, and the width of the rectangle on this side is equal to the length.

6. The fiber grating vibration sensor for garage status detection according to claim 1, characterized in that: The vertical cantilever beam is arranged in a quasi-isosceles trapezoid-rectangle-triangle structure from top to bottom, and a semicircular hole is opened in the quasi-isosceles trapezoid.

7. The fiber grating vibration sensor for garage status detection according to claim 1, characterized in that: The included angle between the horizontal beam and the inclined beam is 120°.

8. The fiber grating vibration sensor for garage status detection according to claim 1, characterized in that: The optical fiber fixing points are set between a set of L-shaped beams located on one side.

9. The fiber grating vibration sensor for garage status detection according to claim 1, characterized in that: The first group of fiber gratings includes a fiber grating number 1 and a fiber grating number 6, the first group of fiber gratings includes a fiber grating number 2 and a fiber grating number 3, and the third group of fiber gratings includes a fiber grating number 4 and a fiber grating number 5; Among them, fiber grating No. 1 is fixed on the horizontal symmetry axis on the left side panel of the platform beam; fiber grating No. 2 is fixed on the vertical symmetry axis position of the vertical cantilever beam, fiber grating No. 3 is fixed on the back of fiber grating No. 2, fiber grating No. 4 is fixed on the connecting beam, and the optical fibers on the left and right sides of the fiber grating are respectively fixed on the first horizontal beam and the second horizontal beam, fiber grating No. 5 is fixed opposite to fiber grating No. 4, and fiber grating No. 6 is fixed on the horizontal symmetry axis of the lower surface of the right side panel of the platform beam, and the horizontal distance from the right protective shell is the same as the horizontal distance from fiber grating No. 1 to the left protective shell.

10. A garage status detection system, characterized in that: The method comprises a fiber Bragg grating vibration sensor and a processor as claimed in any one of claims 1 to 9, wherein the processor is configured to: receive multi-dimensional measurement data obtained by the vibration sensor, demodulate the data through a demodulator, analyze the structural damage in different directions of a carrier carrying a vehicle in a lifting stereo garage, and obtain the working status of the garage; If the data obtained by the demodulator does not have continuous and obvious fluctuations, the working status of the garage is normal; If the data demodulated by the demodulator shows long-term continuous vibration in one or more dimensions, it indicates that the garage infrastructure has structural damage and further investigation is required.

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