A long-distance irregular surface environmental variable sensing device and assembly method thereof

Abstract

The present application discloses a long-distance irregular surface environmental variable sensing device, comprising: a fiber grating; a supporting mechanism, the supporting mechanism is arranged at the inflection point of the surface area to be measured of the object to be measured, and is used to set the fiber grating on the surface area to be measured, and changes with the fluctuation of the surface area to be measured; a positioner, there are two positioners, respectively used to fix the two ends of the fiber grating on the two ends of the surface area to be measured of the object to be measured, at least one of the positioners is provided with a prestressed adaptive mechanism, the prestressed adaptive mechanism is used to adjust the stress on the fiber grating within a set stress range, so that the fiber grating with the pigtail is always in a tensioned state, and can respond to the deformation of the irregular surface under a wide range of temperatures without breaking due to thermal expansion and contraction exceeding its limit. The long-distance irregular surface environmental variable sensing device is convenient for transportation and is convenient for adaptive adjustment according to the bending changes of the surface of the object to be measured.

Description

Technical Field

[0001] This application generally relates to the technical field of environmental monitoring, and particularly to a long-distance irregular surface environmental variable sensing device and its assembly method. Background Art

[0002] Fiber Bragg grating is a passive device that is sensitive to environmental variables such as ambient temperature and stress. It is widely used in long-distance irregular surface environmental variable sensing devices to measure the subtle changes in environmental variables such as temperature and stress generated on the surface of the object to be measured. During measurement, a part of the fiber Bragg grating needs to be fixed on the surface of the object to be measured. Since a part of the fiber Bragg grating has relatively large flexibility, in order to prevent it from being disturbed by other factors such as wind force, existing long-distance irregular surface environmental variable sensing devices generally configure a reinforcing rib for a part of the fiber Bragg grating. Although this facilitates its fixation, when the span of the surface of the object to be measured is large (that is, a part of the fiber Bragg grating and the corresponding reinforcing rib with a long distance are required), the following problems need to be faced: 1. Due to its large volume, the fiber Bragg grating with a configured reinforcing rib is not convenient to be transported to the location of the object to be measured; 2. In order to ensure strong support for the fiber Bragg grating with a large span, the reinforcing rib needs to have a large strength, and in this way, it is not convenient to make adaptive adjustments to the reinforcing rib (fiber Bragg grating) according to the bending change of the surface of the object to be measured. To sum up, how to improve the long-distance irregular surface environmental variable sensing device so that a part of the fiber Bragg grating therein is both convenient for transportation and convenient for making adaptive adjustments according to the bending change of the surface of the object to be measured has become an urgent problem to be solved in this field. Summary of the Invention

[0003] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a long-distance irregular surface environmental variable sensing device and its assembly method that are both convenient for transportation and convenient for making adaptive adjustments according to the bending change of the surface of the object to be measured.

[0004] The specific technical solutions are as follows:

[0005] In a first aspect

[0006] This application provides a long-distance irregular surface environmental variable sensing device, including:

[0007] A fiber Bragg grating having a pigtail and a total length that can span the distance of the surface to be measured;

[0008] A support mechanism, which is arranged at an inflection point on the surface of the object to be measured in the area to be measured greater than a set angle, and is used to mount the fiber Bragg grating on the area to be measured on the surface of the object to be measured and change with the undulation of the area to be measured on the surface of the object to be measured;

[0009] Positioners, there are two of the positioners, which are respectively used to fix both ends of the fiber Bragg grating to both ends of the area to be measured on the surface of the object to be measured. At least one of the positioners is provided with a prestress self-adaptive mechanism, and the prestress self-adaptive mechanism is used to adjust the stress on the fiber Bragg grating with a pigtail within a set stress range, so that the fiber Bragg grating is always in a tensioned state.

[0010] As a further limitation of the present application, the prestress self-adaptive mechanism includes:

[0011] A slider, the slider is used to fix one end of the pigtail of the fiber Bragg grating, and the slider is slidably connected to the base of the positioner;

[0012] An elastic member, the elastic member is connected between the base of the positioner and the slider, and is used to apply a pulling force to the fiber Bragg grating and its pigtail by pulling the slider along a first direction, and the first direction is the direction in which the slider approaches the base of the positioner.

[0013] As a further limitation of the present application, the prestress self-adaptive mechanism further includes:

[0014] A distance adjusting member, one end of the distance adjusting member is connected to the elastic member, and the other end is connected to the base of the positioner, and is used to adjust the distance between the elastic member and the base of the positioner according to the temperature range of the use environment of the device.

[0015] As a further limitation of the present application, the support mechanism includes:

[0016] A connecting member, one end of the connecting member is used to be fixed to the surface of the measured part;

[0017] A track wheel, the track wheel is rotatably connected to the other end of the connecting member;

[0018] When the surface of the measured part at the installation position of the support mechanism is convex, the fiber Bragg grating passes through above the axis of the track wheel;

[0019] When the surface of the measured part at the installation position of the support mechanism is concave, the fiber Bragg grating passes through below the axis of the track wheel.

[0020] As a further limitation of the present application, it further includes:

[0021] A protective shell, there are several protective shells, and they are respectively arranged on each section of the fiber Bragg grating between adjacent support mechanisms.

[0022] Second aspect

[0023] The present application provides an assembly method for assembling the long-distance irregular surface environmental variable sensing device as described above to the surface of the object to be measured, including the following steps:

[0024] Determine the area to be measured on the surface of the object to be measured, and fix the locator at both ends of the area to be measured;

[0025] Obtain the support points on the area to be measured, and install the support mechanism on the support points;

[0026] Connect one end of the fiber Bragg grating to any one of the locators, and pass the other end through each of the support mechanisms and connect it to the other locator;

[0027] Adjust the prestress adaptive mechanism on the locator so that the tension on the fiber Bragg grating is within the set tension range.

[0028] As a further limitation of the present application, the obtaining of the support points on the area to be measured specifically includes the following steps:

[0029] Obtain the angles at the concave and convex inflection points on the area to be measured;

[0030] Judge whether the angle is greater than the set angle;

[0031] When it is greater, determine this position as the support point.

[0032] As a further limitation of the present application, it further includes the following steps:

[0033] Install the protective shell on each section of the fiber Bragg grating between adjacent support mechanisms.

[0034] As a further limitation of the present application, before passing the other end of the fiber Bragg grating through each of the support mechanisms, it further includes the following steps:

[0035] Apply lubricant to the track groove of the track wheel.

[0036] As a further limitation of the present application, it further includes the following steps:

[0037] Obtain the temperature change range of the working environment of the long-distance irregular surface environmental variable sensing device, and adjust the distance adjusting member so that during the process of the length of the grating optical fiber changing with temperature, the tension it receives remains within the set tension range.

[0038] The beneficial effects of the present application are as follows:

[0039] In view of the problem that the reinforcing ribs are inconvenient to transport, and the large-span reinforcing ribs are inconvenient to make adaptive adjustments according to the bending changes of the surface of the object to be measured, the long-distance irregular surface environmental variable sensing device provided by the present application specifically includes: a positioner installed on the surface of the object to be measured and connected to the two ends of the fiber grating respectively, wherein at least one of the positioners is provided with the prestressed adaptive mechanism for adjusting the stress on the fiber grating within the set stress range, which can tighten the fiber grating, so that the fiber grating will not be affected by wind disturbances. In addition, a support mechanism for mounting the fiber grating on the surface of the object to be measured is also provided on the area to be measured on the surface of the object to be measured, so that when the surface of the object to be measured fluctuates at a large angle, the support mechanism can make the fiber grating change roughly with the above fluctuations, so as to overcome the problem of inaccurate measurement of environmental variables caused by the fiber grating being easily affected by wind disturbances due to its own flexible characteristics. Compared with the solution of configuring reinforcing ribs for fiber Bragg grating in the prior art, this solution can not only make the long-distance irregular surface environmental variable sensing device easier to transport as a whole, but also adapt to the bending changes of the surface of the object being measured during installation. Brief Description of the Figures

[0040] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0041] Figure 1 A schematic diagram of the structure of the long-distance irregular surface environmental variable sensing device provided in an embodiment of the present application;

[0042] Figure 2 For Figure 1 Assembly diagram of the medium- and long-distance irregular surface environmental variable sensing device;

[0043] Numbers in the figure: 1, fiber Bragg grating; 2, support mechanism; 3, area to be measured on the surface of the object to be measured; 4, positioner; 40, prestressed adaptive mechanism; 401, slider; 402, positioner base; 403, elastic part; 404, distance adjustment part; 21, connecting part; 22, track wheel; 5, protective shell. Specific implementation method

[0044] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It should also be noted that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] As shown Figure 1 in Figure 1 , it is a schematic structural diagram of the long-distance irregular surface environmental variable sensing device provided by the embodiment of the present application. Among them, the locator 4 on the left may be set as a locator without the prestress adaptive mechanism 40, and the locator 4 on the right may be set as a locator with the prestress adaptive mechanism 40. Of course, both of the above may also be locators with the prestress adaptive mechanism 40, as long as it is ensured that the tensile force on the fiber grating 1 remains within the set tensile force range (in actual operation, generally, one locator 4 with the prestress adaptive mechanism 40 and one locator 4 without the prestress adaptive mechanism 40 are adopted). At this time, the fiber grating 1 remains in a taut state under the action of the above tensile force, so that it will not be easily affected by external wind disturbances and generate corresponding swing errors.

[0047] In addition, when there is a protrusion that hinders the erection of the fiber grating 1 between two adjacent inflection points, although the hindrance angle is less than the set angle, a corresponding support mechanism 2 will also be configured at this place to erect the fiber grating 1 on the surface of the object to be measured at the measurement area 3; similarly, when there is a corresponding depression between two inflection points, although the depression angle is less than the set angle, but it will make the fiber grating 1 farther away from the surface of the object to be measured at the measurement area 3 at this place, a corresponding support mechanism 2 will also be configured at this place to facilitate the installation of the protective shell 5 between the fiber grating 1 at this place and the surface of the object to be measured at the measurement area 3.

[0048] Figure 1 What needs to be introduced emphatically in Figure 1 is the prestress adaptive mechanism 40, which includes: the slider 401, the locator base 402, the elastic member 403 and the distance adjusting member 404. From Figure 1 it can be seen that the elastic member 403 (which can be specifically implemented as a spring) is stretched by the locator base 402 and the slider 401 at both ends thereof, and will always provide a corresponding value of tensile force to the fiber grating 1 to keep it taut. And because this long-distance irregular surface environmental variable sensing device is often placed outdoors for a long time, as the temperature changes, the tightened fiber grating 1 will also have the effect of thermal expansion and contraction. When the external weather changes from hot to cold, the tightened fiber grating 1 will show a corresponding phenomenon of shrinking and shortening, and then the elastic member 403 will be stretched. When it is the coldest, the stretching degree is the largest; correspondingly, when it is the hottest, the stretching degree is the smallest.

[0049] It should be noted here that in order to keep the fiber grating 1 always taut and installed above the area 3 to be measured on the surface of the object to be measured, the elastic member 403 should always be in a stretched state. The tensile force it receives is equal to the stress of the fiber grating 1 and also varies within a set range. In this way, in order to adapt to different working environments, when installing this device, the total distance between one end of the elastic member 403 for connecting with the locator base 402 and the other locator 4 can be adjusted according to the change range of the ambient temperature. In this way, the length of the fiber grating 1 varies within a first set range, and the length of the elastic member 403 varies within a second set range, but the sum of their lengths remains unchanged. Furthermore, the fiber grating 1 can be tautened without being broken, improving the universality of the usage scenarios of this device. As Figure 1 shown in, the distance adjusting member 404 is a screw rod with one end abutted against the slider 401 and the other end threadedly connected to the locator base 403.

[0050] The support mechanism 2 is composed of the connecting member 21 and the track wheel 22, so that the overall extending trend of the fiber grating 1 is roughly the same as the area 3 to be measured on the surface of the object to be measured. As Figure 2As shown, the support mechanism 2 is installed at the vertex of the wave crest or wave trough on the surface of the object to be measured in the area to be measured 3, and this point is the inflection point. At this point, the included angle between the tangents on both sides is greater than the set included angle. Furthermore, it can be ensured that when a stress deformation occurs between two inflection points on the surface of the object to be measured in the area to be measured 3, this deformation can be accurately detected by the fiber Bragg grating 1. Correspondingly, when the support mechanism 2 is installed at the wave crest on the surface of the object to be measured in the area to be measured 3, the fiber Bragg grating 1 needs to pass above the axis of the track wheel 22; when the support mechanism 2 is installed at the wave trough on the surface of the object to be measured in the area to be measured 3, the fiber Bragg grating 1 needs to pass below the axis of the track wheel 22. The specific installation method is to connect the fiber Bragg grating 1 and its pigtail, or use a soft rope to replace the connection between the positioners 4; observe whether it is in contact with the surface of the area to be measured 3, or is too far away. When in contact or away, add the support mechanism 2 to make the fiber Bragg grating 1 and its pigtail, or the soft rope used for testing, fit the surface to be measured. In this way, it can be ensured that the fiber Bragg grating 1 does not contact the surface of the object to be measured in the area to be measured 3 and is tightened by the positioners on both sides. Before assembling the long-distance irregular surface environmental variable sensing device for use, it should be noted that before threading the fiber Bragg grating 1 through the support mechanism 2, it is necessary to apply lubricants such as grease to the track groove of the track wheel 22. After threading is completed, it is necessary to add a protective shell 5 to the fiber Bragg grating 1 between adjacent support mechanisms 2. The protective shell 5 is connected between the fiber Bragg grating 1 and the surface of the object to be measured in the area to be measured 3 to form better protection for the fiber Bragg grating 1. The function of the support mechanism 2 not only makes the fiber Bragg grating 1 and its pigtail more conform to the object surface, but also makes it more convenient to install the protective shell 5 on the undulating surface.

[0051] The above description is only a preferred embodiment of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by mutually replacing the above features with the (but not limited to) technical features with similar functions disclosed in the present application.

Claims

1. A long-distance irregular surface environmental variable sensing device, characterized in that: include: Fiber Bragg gratings with pigtails and a total length that can span the distance of the surface to be measured; A supporting mechanism, the supporting mechanism is arranged at an inflection point greater than a set angle on the surface of the object to be measured, and is used to mount the fiber grating on the surface of the object to be measured and change with the fluctuation of the surface of the object to be measured; Positioners, there are two positioners, which are used to fix the two ends of the fiber Bragg grating at the two ends of the surface of the object to be measured, and at least one of the positioners is provided with a prestressed adaptive mechanism, which is used to adjust the stress on the fiber Bragg grating with a long pigtail within a set stress range, so that the fiber Bragg grating is always in a tensioned state; The prestressed adaptive mechanism comprises: a slider, a positioner base and an elastic member; A slider, the slider is used to fix one end of the fiber grating pigtail, and the slider is slidably connected to the positioner base; An elastic member, the elastic member is connected between the positioner base and the slider, and is used to apply tension to the fiber Bragg grating and its pigtail by pulling the slider along a first direction, wherein the first direction is the direction in which the slider approaches the positioner base; the elastic member should always be in a stretched state, and the tension applied to the elastic member is equal to the stress of the fiber Bragg grating, and the stress of the fiber Bragg grating varies within a set range; the total distance between one end of the elastic member connected to the positioner base and the other positioner is determined based on the range of variation of the ambient temperature; The length of the fiber Bragg grating varies within a first setting range, the length of the elastic member varies within a second setting range, and the sum of the length of the fiber Bragg grating and the length of the elastic member remains unchanged; The supporting mechanism comprises: A connecting piece, one end of which is used to be fixed to an inflection point on the surface of the object to be tested that is greater than a set angle; A track wheel, the track wheel being rotatably connected to the other end of the connecting member; When the inflection point where the support mechanism is installed is a protrusion on the surface of the measured object, the fiber Bragg grating passes above the axis of the track wheel; When the inflection point where the support mechanism is installed is a depression on the surface of the measured object, the fiber Bragg grating passes under the axis of the track wheel.

2. The long-distance irregular surface environmental variable sensing device according to claim 1 is characterized in that: The prestressed adaptive mechanism also includes: A distance adjusting member, one end of which is connected to the elastic member and the other end of which is connected to the positioner base, is used to adjust the distance between the elastic member and the positioner base according to the temperature range of the environment in which the device is used.

3. The long-distance irregular surface environmental variable sensing device according to claim 2, characterized in that: Also includes: A plurality of protective shells are provided, and the protective shells are respectively arranged between the fiber gratings between the adjacent supporting mechanisms and the area to be measured on the surface of the object to be measured.

4. A method for assembling the long-distance irregular surface environmental variable sensing device of claim 3 onto the surface of a measured object, characterized in that: The steps include: Determine the area to be measured on the surface of the object to be measured, and fix the positioner at two ends of the area to be measured on the surface of the object to be measured; Obtaining the inflection point on the surface of the object to be measured that is greater than the set angle, and installing the support mechanism on the inflection point; Connect one end of the fiber Bragg grating to any of the positioners, and pass the other end through each of the supporting mechanisms and connect to another of the positioners; The prestressed adaptive mechanism on the positioner is adjusted so that the tension on the fiber grating is within a set tension range.

5. The assembly method according to claim 4, characterized in that: Obtaining the inflection point on the surface of the object to be measured that is greater than a set angle specifically comprises the following steps: Obtaining the angle of the inflection point of the concave and convex areas on the surface of the object to be measured; Determining whether the angle is greater than the set angle; When it is greater than, the position is determined as the inflection point.

6. The assembly method according to claim 5, characterized in that: Before the other end of the fiber Bragg grating passes through each of the supporting mechanisms, the following steps are also included: Apply lubricant to the track grooves of the track wheels.

7. The assembly method according to claim 6, characterized in that: The following steps are also included: The temperature variation range of the working environment of the long-distance irregular surface environmental variable sensing device is obtained, and the distance adjustment member is adjusted so that the tension exerted on the fiber grating remains within the set tension range during the process of the length of the fiber grating changing with the temperature.

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