阅读说明：本技术 一种智能层式光纤光栅二维应变传感器 (A kind of intelligence laminar fiber grating two-dimensional strain transducer ) 是由 贾书海 卞佳铭 彭俊 张硕 陈继忠 于 2019-08-26 设计创作，主要内容包括：本发明公开了一种智能层式光纤光栅二维应变传感器,包括刻在同一根保偏光删上的三个双重光纤光栅,所述保偏光删弯折呈等边三角形,三个双重光纤光栅分别布置在一边上,第一双重光纤光栅和第二双重光纤光栅均为应变测量光栅,第三双重光纤光栅为温度补偿光栅,且三个双重光纤光栅的中心波长不同；其中,三个双重光纤光栅和一根保偏光纤均被封装于封装膜内,在第三双重光纤光栅外设有有U型封装区,且U型封装区仅U型开口区域与封装膜连接。本发明的传感器在测量时可以表贴在不规则曲面表面进行应变测量,有效提高空间分辨率,使用时安装灵活,且由于其中一根光纤光栅为温度补偿光纤光栅因而能够实现温度补偿,环境适应性好。(The invention discloses a kind of intelligent laminar fiber grating two-dimensional strain transducers, the three dual fiber gratings deleted including being engraved in same root polarization-maintaining light, it is in equilateral triangle that the polarization-maintaining light deletes bending, three dual fiber gratings are arranged on one side, first dual fiber grating and the second dual fiber grating are strain measurement grating, third dual fiber grating is temperature-compensating grating, and the central wavelength of three dual fiber gratings is different；Wherein, three dual fiber gratings and a polarization maintaining optical fibre are packaged in encapsulating film, have been externally provided with U-shaped encapsulation region in third dual fiber grating, and U-shaped encapsulation region is only connect in U-shaped opening region with encapsulating film.Sensor of the invention can carry out strain measurement on Irregular Boundary Surface surface with Surface Mount in measurement, effectively improve spatial resolution, it is flexible for installation when use, and due to wherein fiber grating be temperature compensation optical fiber grating thus can be realized temperature-compensating, good environmental adaptability.)

1. a kind of intelligence laminar fiber grating two-dimensional strain transducer, which is characterized in that including being engraved in same root polarization maintaining optical fibre (6) On three dual fiber gratings, the polarization maintaining optical fibre (6) bending is in equilateral triangle, and three dual fiber gratings are respectively arranged Triangle on one side on, the first dual fiber grating (1) and the second dual fiber grating (2) are strain measurement grating, Three dual fiber gratings (3) are temperature-compensating grating, and the central wavelength of three dual fiber gratings is different；

Wherein, three dual fiber gratings and a polarization maintaining optical fibre (6) are packaged in encapsulating film (5), in the dual light of third Fine grating (3) is externally provided with U-shaped encapsulation region, and only U-shaped opening region is connect with encapsulating film (5) for U-shaped encapsulation region.

2. intelligence laminar fiber grating two-dimensional strain transducer according to claim 1, which is characterized in that the first dual light Side where Bian Junyu third dual fiber grating (3) where fine grating (1), the second dual fiber grating (2) is in arc transition.

3. intelligence laminar fiber grating two-dimensional strain transducer according to claim 1, which is characterized in that U-shaped encapsulation region Bottom surface is provided with one layer of separation layer that can be extracted out (4).

4. intelligence laminar fiber grating two-dimensional strain transducer according to any one of claims 1 to 3, feature exist In encapsulating film (5) is polyimides or waterglass film.

5. intelligence laminar fiber grating two-dimensional strain transducer according to any one of claims 1 to 3, feature exist In the polarization maintaining optical fibre (6) is birefringent polarization maintaining optical fibre.

6. intelligence laminar fiber grating two-dimensional strain transducer according to any one of claims 1 to 3, feature exist In the intelligence laminar fiber grating two-dimensional strain transducer structure is in Y-shaped.

Technical field

The invention belongs to Fiber Grating Sensors Technology fields, are related to a kind of intelligent laminar fiber grating two-dimensional strain sensing Device.

Background technique

With reaching its maturity for optical fiber sensing technology, fiber Bragg grating strain sensor is widely used to build a bridge, machine The fields such as tool and electric power.Compared to such as traditional resistance strain gage sensor, fiber Bragg grating strain sensor has many advantages, such as, example Such as electromagnetism interference, electrical insulation capability be good, safe and reliable, corrosion-resistant, stable chemical performance, small in size, light-weight.

Strain measurement is the important means of monitoring of structures safe condition, needed for different application and different materials structure Strain resolution and strain range are distinct.It is all only used for mostly currently based on the strain sensing devices of fiber grating one-dimensional Strain measurement, few fiber Bragg grating strain sensor parts suitable for Two-dimensional strain measurement.CN106767486A discloses one Kind fiber grating two-dimensional strain sensitization sensor and its packaging method, structure are that four installation pins are connected on an annulus, Two fiber grating vertical distributions, and both ends are fixed on annulus.Two fiber gratings vertically fixed can perceive two The strain of different directions, to realize that Two-dimensional strain measures.But its volume is big, installation is inconvenient, can only measurement rules plane Strain, and can not achieve temperature-compensating.CN107218898A discloses a kind of star fiber optic grating of surface Two-dimensional strain detection Foil gauge, it is made of star metallic elastic platelet substrate and three Bragg gratings, draws again by three installations Foot is connect with testee.But the above sensor can only measurement rules planar strain, be not suitable for small size object Surface topography complexity planar strain measurement, and do not have temperature-compensating, be not suitable for the big environment of the temperature difference.

Summary of the invention

In order to overcome the disadvantages of the above prior art, the purpose of the present invention is to provide a kind of intelligent laminar fiber gratings two Strain transducer is tieed up, the sensor bulk is small, and it is easy for installation, small size body surface Two-dimensional strain can be measured, and can be real Existing temperature-compensating, good environmental adaptability.

In order to achieve the above object, the present invention is achieved by the following scheme:

The invention discloses a kind of intelligent laminar fiber grating two-dimensional strain transducers, including are engraved in same root polarization maintaining optical fibre On three dual fiber gratings, polarization maintaining optical fibre bending is in equilateral triangle, and three dual fiber gratings are arranged in Triangle on one side on, the first dual fiber grating and the second dual fiber grating are strain measurement grating, the dual light of third Fine grating is temperature-compensating grating, and the central wavelength of three dual fiber gratings is different；

Wherein, three dual fiber gratings and a polarization maintaining optical fibre are packaged in encapsulating film, in third dual fiber Grating is externally provided with U-shaped encapsulation region, and U-shaped encapsulation region is only connect in U-shaped opening region with encapsulating film.

Preferably, Bian Junyu third dual fiber grating institute where the first dual fiber grating, the second dual fiber grating It is in arc transition on side.

Preferably, U-shaped encapsulation region bottom surface is provided with one layer of separation layer that can be extracted out.

It is further preferred that encapsulating film is polyimides or waterglass film.

It is further preferred that the polarization maintaining optical fibre is birefringent polarization maintaining optical fibre.

It is further preferred that the intelligence laminar fiber grating two-dimensional strain transducer structure is in Y-shaped.

Compared with prior art, the invention has the following advantages:

Intelligence laminar fiber grating two-dimensional strain transducer disclosed by the invention, three dual fiber gratings is engraved in same On root polarization maintaining optical fibre, and polarization maintaining optical fibre is bent to form equilateral triangle, the volume of sensor can be effectively reduced, makes its structure It is compact, small size body surface Two-dimensional strain can be measured, when measurement can carry out strain survey on Irregular Boundary Surface surface with Surface Mount Amount, effectively improves spatial resolution, and when use is flexible for installation, and since a wherein fiber grating is temperature compensation optical fiber grating Thus it can be realized temperature-compensating, good environmental adaptability.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of intelligent laminar fiber grating two-dimensional strain transducer of the invention；

Fig. 2 is the dual fiber grating schematic diagram carved on polarization maintaining optical fibre；

Fig. 3 is sensor of the invention principle Analysis figure；Wherein, (a) is the strain shape of three dual fiber gratings State relational graph；It (b) is dual fiber grating to the sensing principle figure of Two-dimensional strain.

Wherein: 1- the first dual fiber grating；2- the second dual fiber grating；3- third dual fiber grating；4- isolation Layer；5- encapsulating film；6- polarization maintaining optical fibre.

Specific embodiment

In order to enable those skilled in the art to better understand the solution of the present invention, below in conjunction in the embodiment of the present invention Attached drawing, technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is only The embodiment of a part of the invention, instead of all the embodiments.Based on the embodiments of the present invention, ordinary skill people The model that the present invention protects all should belong in member's every other embodiment obtained without making creative work It encloses.

It should be noted that description and claims of this specification and term " first " in above-mentioned attached drawing, " Two " etc. be to be used to distinguish similar objects, without being used to describe a particular order or precedence order.It should be understood that using in this way Data be interchangeable under appropriate circumstances, so as to the embodiment of the present invention described herein can in addition to illustrating herein or Sequence other than those of description is implemented.In addition, term " includes " and " having " and their any deformation, it is intended that cover Cover it is non-exclusive include, for example, the process, method, system, product or equipment for containing a series of steps or units are not necessarily limited to Step or unit those of is clearly listed, but may include be not clearly listed or for these process, methods, product Or other step or units that equipment is intrinsic.

The invention will be described in further detail with reference to the accompanying drawing:

Referring to Fig. 1 and Fig. 2, a kind of intelligent laminar fiber grating two-dimensional strain transducer, including 1 bending is in equilateral triangle The polarization maintaining optical fibre 6 of shape, the region of equilateral triangle are the working region of sensor, therefore on three sides of the polarization maintaining optical fibre 6 It is carved with a dual fiber grating respectively, two neighboring dual fiber grating is mutually 60 ° of angle distributions, and three dual fiber light The central wavelength of grid is different；Wherein, the first dual fiber grating 1 and the second dual fiber grating 2 are strain measurement grating, the Three dual fiber gratings 3 are temperature-compensating grating；Three dual fiber gratings and a polarization maintaining optical fibre 6 are packaged in encapsulating film In 5, it is externally provided with U-shaped encapsulation region in third dual fiber grating 3, and only U-shaped opening region and encapsulating film 5 connect for U-shaped encapsulation region It connects；

Encapsulating film 5 has two layers, and above-mentioned polarization maintaining optical fibre 6 and three dual fiber gratings are encapsulated in it by heat pressing process In, so that overall package structure is in Y-shaped.

First dual fiber grating 1,2 place Bian Junyu third dual fiber grating of the second dual fiber grating, 3 place side In arc transition, the area of delta-shaped region can be further decreased, to make stable structure, compact.

U-shaped encapsulation region bottom surface is provided with one layer of separation layer that can be extracted out 4, should after sensor is pasted onto testee completely Separation layer 4 can be extracted.

Referring to Fig. 3, (a) is the strain regime relational graph of three dual fiber gratings in Fig. 3；It (b) is dual fiber grating To the sensing principle figure of Two-dimensional strain.In use, the sensor of intelligent layer encapsulation is secured on testee, wherein third The region of dual fiber grating 3 and object are without directly contacting.When object is deformed, the first dual fiber grating 1 and second Dual fiber grating 2 is generated strain by stress.The axial strain ε of fiber grating₁, ε₃Lead to the two of dual fiber grating It is Δ λ that drift value, which integrally occurs, for the central wavelength of a reflected light_ZⅠ, Δ λ_ZⅡ.The transverse strain ε of fiber grating₂, ε₄Lead to dual light It is Δ λ that drift value, which occurs, for the spacing between the central wavelength of two reflected lights of fine grating_hⅠ, Δ λ_hⅡ.Testee or extraneous temperature Degree can cause the reflection center wavelength of light of third dual fiber grating 3, and integrally the amount of shifting is Δ λ_ZⅢ, in two reflected lights It is Δ λ that drift value, which occurs, for the spacing between cardiac wave is long_hⅢ.The relationship of wavelength shift and strain and temperature is as shown in formula.

Δλ_ZI=K_zεε₁+K_ZTT

Δλ_hI=K_hεε₂+K_hTT

Δλ_ZⅡ=K_zεε₃+K_ZTT

Δλ_hⅡ=K_hεε₄+K_hTT

Δλ_ZⅢ=K_ZTT, Δ λ_hⅢ=K_hTT

Wherein K_zεAnd K_zεThe respectively axial direction of dual fiber grating and transverse strain sensitivity coefficient, K_ZTAnd K_hTIt is respectively double The axial direction and transverse temperature sensitivity coefficient of weight fiber grating.

Above 6 equations, 5 unknown numbers, simultaneous solution you can get it ε₁, ε₂, ε₃, ε₄.Measured object axial strain ε_x, ε_yWith Tangential strain γ_xyWith ε₁, ε₂, ε₃, ε₄Relationship as shown in formula.

Wherein ε_x, ε_yThe respectively strain of x-axis and y-axis direction, γ_xyFor shear strain.α₁, α₂, α₃, α₄Respectively answer accordingly The angle changed direction with x-axis, once sensor be fixed on each angle of body surface it is also known that.Above 4 equations 3 are not Know number, simultaneous equations you can get it ε_x, ε_yAnd γ_xy.The then strain and shear strain of two orthogonal directions of testee It can measure and obtain.

The above content is merely illustrative of the invention's technical idea, and this does not limit the scope of protection of the present invention, all to press According to technical idea proposed by the present invention, any changes made on the basis of the technical scheme each falls within claims of the present invention Protection scope within.