CN117805985A - A fence sensing optical cable based on distributed grating array technology - Google Patents

Abstract

The invention discloses a fence sensing optical cable based on a distributed grating array technology, which belongs to the technical field of safety monitoring and comprises the following components: the optical fiber demodulation device comprises a stress sensing optical unit, an optical cable outer sheath, a first tensile member and a second tensile member, wherein the stress sensing optical unit comprises a packaging tube and a grating array tight-sleeved optical fiber which is arranged along the length direction of the packaging tube and is equal in length, and the grating array tight-sleeved optical fiber is connected with a demodulation instrument; the optical cable outer sheath is provided with a fixing part which is stretched by external force and a sensing part which is connected with the fixing part and deforms along with the stretching of the fixing part, the fixing part is used for being connected with the fence frame through two ends, and the sensing part is wrapped on the stress sensing light unit; the first tensile member and the second tensile member are respectively packaged in the fixed part and the sensing part; the invention can judge whether the man-made invasion is caused, can shield false alarm signals caused by strong wind and animals, can realize all-day and all-weather monitoring, and has very important practical value.

Description

A fence sensing optical cable based on distributed grating array technology

Technical field

The invention relates to the technical field of security monitoring, and in particular to a fence sensing optical cable based on distributed grating array technology.

Background technique

At present, there are a large number of institutions or projects in China that involve national secrets, people's livelihood security, and high economic benefits. The area of these institutions or engineering parks is generally large, and manual patrols become inefficient and unsafe. Therefore, efficient and intelligent security monitoring is installed. Equipment or systems have become particularly necessary to detect human intrusions and vandalism and to respond quickly, locate, warn and expel them.

At present, the main solutions include infrared cameras, vibrating perimeter optical cables, electronic fences, zone-type fence sensors, etc. For example, the publication number CN112309061A provides an infrared fence, which includes a controller, an alarm device connected to the controller, and at least two infrared fence posts connected to the controller. The infrared fence posts include a column and a plurality of columns located on the column. The infrared transmitting device on the infrared fence column and a plurality of infrared receiving devices arranged on the column. The infrared transmitting device on the infrared fence column emits infrared rays to the infrared receiving device on the adjacent infrared fence column, so as to achieve the goal of transmitting infrared light between the two adjacent infrared fence columns. An infrared grating is formed between them. The invention emits infrared rays through an infrared transmitting device on an infrared fence post to an infrared receiving device on an adjacent infrared fence post to form an infrared grating between two adjacent infrared fence posts. When a person passes by the infrared grating, the infrared grating is cut off. At this time, some infrared receiving devices cannot detect infrared rays. The controller controls the alarm device to sound an alarm to warn construction workers in the construction area and non-construction personnel who accidentally enter the construction area to ensure the safety of the construction site.

In the prior art, when an infrared transmitting device and an infrared receiving device are used to form an infrared grating or a vibrating perimeter optical cable is used for monitoring, it is easily affected by heavy rain or fog, or the sensor optical cable is accidentally touched during strong winds or biological invasions, thereby triggering the fence alarm device to sound an alarm. There are problems such as false alarms caused by weather influences and biological invasions.

Contents of the invention

The purpose of the present invention is to overcome the above technical deficiencies and propose a fence sensing optical cable based on distributed grating array technology to solve the problem in the existing technology that fences are susceptible to heavy rain, heavy fog, and occlusion, and there are errors caused by strong winds and biological intrusions. technical issues such as reporting.

In order to achieve the above technical objectives, the technical solution of the present invention provides a fence sensing optical cable based on distributed grating array technology, including: a stress sensing light unit, an outer sheath of the optical cable, a first tensile member and a second tensile member, The stress sensing light unit includes a packaging tube and a grating array tight-buffered optical fiber arranged at equal lengths along the length direction of the packaging tube. The grating array tight-buffered optical fiber is connected to the demodulation instrument; the outer sheath of the optical cable has a A fixed part that is stretched by an external force, and a sensing part that is connected to the fixed part and deforms as the fixed part is stretched. The fixed part is used to connect the fence frame through both ends, and the sensing part Wrapped in the stress sensing light unit; the first tensile member and the second tensile member are respectively packaged in the fixing part and the sensing part.

In some embodiments, the first tensile member includes a fixing steel wire, the fixing steel wire is fixed in the fixing part of the optical cable outer sheath, and extends along the length direction of the fixing part so that both sides of the fixing steel wire The ends protrude or are flush with the two ends of the fixed part, and the two ends of the fixed steel wire are connected to the fence frame. The fixed steel wire is centrally arranged in the fixed part, and its diameter is 2.5mm.

In some embodiments, the second tensile member includes an adjusting steel wire, which is disposed on the side of the stress sensing light unit and fixed in the sensing part of the outer sheath of the optical cable and connected with the The stress sensing light units are spaced apart, and both ends of the adjusting steel wire extend along the length direction of the sensing part to both ends of the fixing part. The adjustment steel wires are arranged side by side and spaced apart from the stress sensing light unit. There are two adjustment steel wires. The two adjustment steel wires are respectively provided near and away from the stress sensing light unit and away from the outer sheath of the optical cable. One side of the fixed part has a diameter of 0.5mm.

In some embodiments, both sides between the fixing part and the sensing part are recessed inward to form a recessed part, the recessed part penetrates the optical cable outer sheath in the length direction, and the recessed part is transversely The width of the cross section gradually increases in a direction away from the outer sheath of the optical cable.

Compared with the prior art, the beneficial effects of the present invention include: through the provided stress sensing light unit, optical cable outer sheath, first tensile member and second tensile member, the fixing part can be laterally fixed to the fence frame through both ends. In order to sense the tensile force generated by external intrusion, the first tensile member is packaged in the fixed part to improve the tensile performance of the fixed part and prevent the outer sheath of the optical cable from being damaged after being deformed by tensile force;

When the fixed part is stretched, the sensing part will deform at the corresponding position. Since the stress sensing light unit is wrapped in the sensing part, the stress generated by the deformation will be transmitted to the stress sensing light unit inside the fence sensing optical cable, causing The wavelength of the array grating changes, and the stress sensing light unit has grating array tight-buffered optical fibers arranged at equal lengths along the length of the packaging tube. The grating array optical fiber technology is used to form multiple monitoring areas outside the outer sheath of the optical cable. According to Corresponding to the wavelength changes of the array grating generated in the monitoring area, precise positioning of foreign object intrusion can be achieved;

Since the second tensile member is encapsulated in the sensing part, the amount of deformation of the sensing part when stretched by the fixed part can be changed, the tensile performance of the sensing part can be improved, and the deformation of the stress sensing light unit can be controlled within Within the measurement range of the demodulation instrument, when affected by weather interference and other biological attacks, the outer sheath of the optical cable will not deform or can control the deformation within the warning range. It can determine whether there is human intrusion and can shield the damage caused by strong winds and animals. False alarm signals can be monitored around the clock and around the clock, which has very important practical value.

Description of drawings

Figure 1 is a schematic cross-sectional structural diagram of an embodiment of a fence sensing optical cable based on distributed grating array technology provided by the present invention;

Figure 2 is a schematic structural diagram of the stress sensing light unit of the fence sensing optical cable based on distributed grating array technology in Figure 1;

FIG. 3 is a schematic diagram of the structure of the fence sensor optical cable based on the distributed grating array technology in FIG. 1 during installation.

In the picture:

1. stress sensing optical unit; 11. packaging tube; 12. tight casing; 13. grating array optical fiber;

2. Outer sheath of optical cable; 21. Fixed part; 22. Sensing part; 23. Recessed part;

3. The first tensile member;

4. Second tensile member; 5. Fence frame; 6. Fence sensing optical cable.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention and are not intended to limit the present invention.

As shown in Figures 1 to 3, the present invention provides a fence sensing optical cable based on distributed grating array technology, including: a stress sensing light unit 1, an optical cable outer sheath 2, a first tensile member 3 and a second Tensile member 4, the stress sensing light unit 1 includes a packaging tube 11 and a grating array tight-buffered optical fiber arranged at equal lengths along the length direction of the packaging tube 11, and the grating array tight-buffered optical fiber is connected to a demodulation instrument; The optical cable outer sheath 2 has a fixing part 21 for being stretched by external force, and a sensing part 22 connected to the fixing part 21 and deformed as the fixing part 21 is stretched. The fixing part 21 Used to connect the fence frame 5 through both ends, the sensing part 22 is wrapped in the stress sensing light unit 1; the first tensile member 3 and the second tensile member 4 are respectively packaged in the fixed part 21 and the sensing part 22 .

In this solution, the outer sheath 2 of the optical cable has a fixed part 21 for being stretched by external force, and a sensing part 22 connected to the fixed part 21 and deformed as the fixed part 21 is stretched. During implementation, , the fixed part 21 is laterally fixed on the fence frame 5 through both ends to sense the tensile force generated by external intrusion, and the first tensile member 3 is packaged in the fixed part 21 to improve the tensile performance of the fixed part 21 and prevent The optical cable outer sheath 2 is damaged after being deformed by tension; when the fixed part 21 is stretched, the sensing part 22 will deform at the corresponding position. Since the stress sensing light unit 1 is wrapped in the sensing part 22, the deformation will occur. The stress will be transmitted to the stress sensing light unit 1 inside the fence sensing optical cable, which will cause the array grating wavelength to change, and the stress sensing light unit 1 has grating array tight-buffered optical fibers arranged at equal lengths along the length direction of the packaging tube 11. Thereby, multiple monitoring areas are formed outside the outer sheath 2 of the optical cable. According to the wavelength changes of the array grating generated in the corresponding monitoring areas, precise positioning of foreign object intrusion can be achieved. Since the second tensile member 4 is packaged in the sensing part 22, it can Change the deformation amount of the sensing part 22 under the stretching of the fixed part 21, improve the tensile performance of the sensing part 22, control the deformation of the stress sensing light unit 1 within the measurement range of the demodulation instrument, and at the same time make the receiving part When weather interference and other biological attacks occur, the outer sheath 2 of the optical cable will not deform or can control the deformation within the warning range to avoid false alarms. It has a simple structure, simple installation and maintenance, and can realize all-day and all-weather monitoring.

Preferably, the packaging tube 11 is a metal spiral armored tube, and the grating array tight-buffered optical fiber includes a tight-buffered tube 12 and a grating array optical fiber 13 arranged in the tight-buffered tube 12. The grating array optical fiber 13 is a complete optical fiber, and the inside of the optical fiber is equidistantly spaced. Set the grating as a sensor, and after it is specially packaged into a cable, it can detect strain or stress changes. The spacing can be predetermined based on various factors such as measurement accuracy, demodulation requirements, and fence frame spacing parameters, which can increase the coverage. Long monitoring distance.

Specifically, the grating inside the laid fence sensing optical cable is positioned and initially calibrated using a demodulator. When a certain external stress is encountered, the grating transmits the optical signal to the demodulator and the output of the demodulator is observed. As a result, the obtained wavelength and the initial wavelength are finally compared and recorded by observing the spectrum. Among them, a deformation threshold can be set for the deformation generated by the fence sensing optical cable. When it is less than the deformation threshold, it is considered to be external interference, and when it is greater than or equal to the deformation threshold, it is considered to be an effective intrusion. By setting the threshold in this way, the influence of small forces such as wind swaying and animal parking swaying on the protective cable can be removed, reducing and avoiding the occurrence of false alarms. When the fence sensing optical cable is at the deformation threshold, the stress sensing light unit 1 will produce deformation, causing the wavelength of the array grating to change, which shows a wavelength change threshold, which can be set by the demodulation instrument to determine whether it is a human intrusion.

Furthermore, since the optical cable outer sheath 2 needs to deform when being stretched, in some possible embodiments, the optical cable outer sheath 2 is made of LLDPE (linear low-density polyethylene) material, which has high hardness, It has the advantages of good toughness, good temperature resistance and weather resistance, and tear resistance.

The first tensile member 3 is used to enhance the tensile performance of the fixing part 21. In some possible embodiments, the first tensile member 3 includes a fixing steel wire, which is fixed to the fixing part of the optical cable outer sheath 2. 21, and extend along the length direction of the fixed part 21 so that the two ends of the fixed steel wire protrude or are flush with the two ends of the fixed part 21, and both ends are fixedly connected to the corresponding fence frame 5 to form a stable Monitor the tension area. Wherein, the fixing steel wire is centrally arranged in the fixing part 21 .

Specifically, the fixed steel wire is a phosphated steel wire with a diameter of 2.5 mm, which has high tensile and compressive properties. When the optical cable is laid, it is clamped and locked on the optical cable outside the steel wire, which can well protect the optical cable from being stretched. In addition, the fixed optical cable is clamped in the cross section of the steel wire to avoid being clamped in the sensitive area of the optical unit to cause erroneous signals.

The second tensile member 4 can enhance the tensile performance of the sensing part 22. In some possible embodiments, the second tensile member 4 includes an adjustment steel wire, and the adjustment steel wire is provided on the stress sensing light unit 1 and fixed in the sensing part 22 of the optical cable outer sheath 2, spaced apart from the stress sensing light unit 1, and the two ends of the adjusting steel wire extend along the length direction of the sensing part 22 to both ends of the fixed portion 21 .

In this embodiment, the adjustment steel wire and the stress sensing light unit 1 are arranged in parallel and spaced apart. There are two adjusting steel wires, and the two adjusting steel wires are respectively arranged on the side of the stress sensing light unit 1 close to and away from the fixing part 21 of the optical cable outer sheath 2. During implementation, the sensing part 22 Located directly below the fixed part 21, the fixed part 21 is used to be stretched above in case of intrusion. Since artificial intrusion will press the optical cable downward, the pressed part of the optical cable will deform downward. The two adjusting steel wires are set at the position where the deformation occurs. direction, so that it has good tensile protection effect.

Specifically, the adjusting steel wire is a phosphated steel wire with a diameter of 0.5mm. Its thickness can also be flexibly set according to the actual monitored environmental conditions and alarm threshold settings, so that it has certain tensile protection performance and sensitivity adjustment performance. .

In other possible implementations, the first tensile member 3 and the second tensile member 4 located in the outer sheath 2 of the optical cable are not limited to steel wires, but may also be other structural members.

In some possible embodiments, the two sides between the fixing portion 21 and the sensing portion 22 are recessed inward to form a recessed portion 23, and the recessed portion 23 passes through the optical cable outer sheath 2 in the length direction. The width of the cross section of the recessed portion 23 increases in sequence in the direction away from the optical cable outer sheath 2 to form a triangular cross section. This arrangement can reduce the influence of the deformation of the fixing portion 21 on the sensing portion 22, thereby reducing the influence of factors such as the environment and animals to a certain extent, and preventing false alarms other than human intrusion.

The above embodiments are merely multiple possible implementations of the embodiments of the present application, and the embodiments of the present application are not limited thereto.

When the fence sensing optical cables 6 are installed, they can be arranged sequentially on the fence frame 5 along the height direction. In this embodiment, there are three fence sensing optical cables 6 , and one fence sensing optical cable is arranged between the middle parts of the fence frame 5 Two parallel and spaced fence sensing optical cables 6 are arranged between the optical cable 6 and the top of the fence frame 5, and the top fence sensing optical cable 6 is located above the fence.

Preferably, the stress sensing optical unit 1 in the present invention is based on grating array fiber technology. Distributed array grating engraves gratings into the fiber before coating the fiber. Compared with traditional fiber grating, the grating array fiber 13 has the function of no welding. It has the advantages of high reliability, high production efficiency, low preparation cost, long reuse length, easy cable packaging, and small sensing grating spacing. The above-mentioned grating array optical fiber 13 is placed inside the metal spiral armor tube in the form of a tight-buffered optical fiber, and 10~20mm hot melt adhesive is injected into the metal spiral armor at equal intervals to fix the metal spiral armor and the grating array tight-buffered optical fiber. The cable formation process The stress sensing light unit 1 is stretched, so that the grating array tightly packed optical fiber is stressed to form a certain degree of stretching. The above-mentioned fence sensing optical cable is stretched, laid and installed as an initial standard parameter signal, and then based on a large number of previous experimental results, a wavelength change value is set that is judged to be a human intrusion.

In the present invention, through the stress sensing light unit 1, the optical cable outer sheath 2, the first tensile member 3 and the second tensile member 4, the fixing part 21 can be laterally fixed on the fence frame 5 through both ends to sense external intrusion. The tensile force generated by the fiber optic cable is packaged in the fixing part 21 by the first tensile member 3 to improve the tensile performance of the fixing part 21 and prevent the outer sheath 2 of the optical cable from being damaged after being deformed by the tensile force. When the fixed part 21 is stretched, the sensing part 22 will deform at the corresponding position. Since the stress sensing light unit 1 is wrapped in the sensing part 22, the stress generated by the deformation will be transmitted to the stress inside the fence sensing optical cable. The sensing light unit 1 will cause the array grating wavelength to change, and the stress sensing light unit 1 has grating array tight-buffered optical fibers arranged at equal lengths along the length direction of the packaging tube 11. The grating array optical fiber technology is used to protect the optical cable. Multiple monitoring areas are formed outside the cover 2. According to the wavelength changes of the array grating generated in the corresponding monitoring areas, precise positioning of foreign object intrusion can be achieved.

The present invention encapsulates the second tensile member 4 in the sensing part 22, which can change the deformation amount of the sensing part 22 under the stretching of the fixed part 21, improve the tensile performance of the sensing part 22, and can reduce the stress. The deformation of the sensing light unit 1 is controlled within the measurement range of the demodulation instrument. At the same time, when it is disturbed by weather or invaded by other organisms, the outer sheath 2 of the optical cable will not deform or can control the deformation within the warning range, and it can be determined whether it is artificial or not. Intrusion can shield false alarm signals caused by strong winds and animals, and can achieve all-day and all-weather monitoring, which has very important practical value.

In the description of this application, it should be noted that the orientation or positional relationship indicated by the terms "upper" and "lower" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application and simplifying the description. It is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as a limitation on the present application. Unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection, It can also be an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be an internal connection between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

It should be noted that in this application, relational terms such as “first” and “second” are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply There is no such actual relationship or sequence between these entities or operations. Furthermore, the terms "comprises," "comprises," or any other variations thereof are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also those not expressly listed other elements, or elements inherent to the process, method, article or equipment. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article, or apparatus that includes the stated element.

The above-described specific embodiments of the present invention do not limit the scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention shall be included in the protection scope of the claims of the present invention.

Claims (10)

1. Fence sensing optical cable based on distributed grating array technology, characterized by comprising: the stress sensing optical unit, the optical cable outer sheath, the first tensile member and the second tensile member,

the stress sensing light sensing unit comprises a packaging tube and a grating array tight-sleeved optical fiber which is arranged along the length direction of the packaging tube and is equal in length, and the grating array tight-sleeved optical fiber is connected with a demodulation instrument;

the optical cable outer sheath is provided with a fixing part which is stretched by external force and a sensing part which is connected with the fixing part and deforms along with the stretching of the fixing part, the fixing part is used for being connected with a fence frame through two ends, and the sensing part is wrapped in the stress sensing light unit;

the first tensile member and the second tensile member are respectively encapsulated in the fixing portion and the sensing portion.

2. The fence sensing optical cable based on a distributed grating array technology according to claim 1, wherein the first tensile member includes a fixing wire fixed in a fixing portion of the cable jacket and extending in a length direction of the fixing portion such that both ends of the fixing wire protrude or are flush with both ends of the fixing portion, and both ends of the fixing wire are connected to the fence frame.

3. The fence sensing fiber optic cable based on distributed grating array technology of claim 2, wherein the securing wire is centrally disposed within the securing portion.

4. A fence sensing fiber optic cable based on distributed grating array technology as in claim 3, wherein the diameter of the fixed wire is 2.5mm.

5. The fence sensing optical cable based on a distributed grating array technology according to claim 1, wherein the second tensile member includes an adjusting wire disposed at a side of the stress sensing optical unit and fixed in the sensing portion of the cable outer sheath and spaced apart from the stress sensing optical unit, and both ends of the adjusting wire extend to both ends of the fixing portion along a length direction of the sensing portion.

6. The fence sensing fiber optic cable based on distributed grating array technology of claim 5, wherein the tuning wires are juxtaposed and spaced apart from the stress sensing light units.

7. The fence sensing optical cable based on a distributed grating array technology according to claim 6, wherein two adjusting wires are provided, and the two adjusting wires are respectively arranged on one side of the stress sensing light sensing unit, which is close to and away from the fixing part of the optical cable outer sheath.

8. The pen sensing cable based on distributed grating array technology according to claim 7, wherein the diameter of the tuning wire is 0.5mm.

9. The pen sensing cable based on the distributed grating array technology according to claim 1, wherein both sides between the fixing portion and the sensing portion are recessed inward to form a recess portion penetrating through the cable outer sheath in a length direction.

10. The pen sensing cable based on distributed grating array technology according to claim 9, wherein the width of the recess cross section increases sequentially in a direction away from the cable jacket.