CN203772461U - Stress monitoring device - Google Patents
Stress monitoring device Download PDFInfo
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- CN203772461U CN203772461U CN201420087557.9U CN201420087557U CN203772461U CN 203772461 U CN203772461 U CN 203772461U CN 201420087557 U CN201420087557 U CN 201420087557U CN 203772461 U CN203772461 U CN 203772461U
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- optical fiber
- grating
- sidewall
- fiber
- response body
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- 238000012806 monitoring device Methods 0.000 title abstract description 6
- 239000013307 optical fiber Substances 0.000 claims abstract description 65
- 239000000835 fiber Substances 0.000 claims abstract description 47
- 238000004804 winding Methods 0.000 claims abstract description 5
- 230000004044 response Effects 0.000 claims description 33
- 239000012858 resilient material Substances 0.000 claims description 3
- 230000007613 environmental effect Effects 0.000 abstract description 9
- 230000001681 protective effect Effects 0.000 abstract description 6
- 230000003287 optical effect Effects 0.000 abstract description 5
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract 1
- 238000000034 method Methods 0.000 description 19
- 238000005259 measurement Methods 0.000 description 15
- 238000007667 floating Methods 0.000 description 12
- 230000008569 process Effects 0.000 description 8
- 238000012544 monitoring process Methods 0.000 description 6
- 229910000679 solder Inorganic materials 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005538 encapsulation Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000012935 Averaging Methods 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000004873 anchoring Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 238000007747 plating Methods 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229920000715 Mucilage Polymers 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 238000005219 brazing Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007772 electroless plating Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000006263 metalation reaction Methods 0.000 description 1
- 238000001465 metallisation Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 238000012536 packaging technology Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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Abstract
The utility model provides a stress monitoring device. The stress monitoring device comprises a fiber bragg grating, an optical fiber and a strain body. A protective shell covering the sidewall is fixedly arranged on the sidewall of the strain body. A fiber outlet hole is formed in the protective shell. A protective baffle is arranged around the fiber outlet hole. In a layout space between the protective shell and the sidewall of the strain body, the first end of the optical fiber is fixed to the sidewall of the strain body, and the optical fiber is wound and fixed to the sidewall of the strain body according to a certain winding distance in the axial direction of the strain body. The fiber bragg grating is arranged on the optical fiber in the axial direction of the optical fiber. The second end of the optical fiber extends out of the protective shell through the fiber outlet hole and is connected with a wideband incident light source. A fiber bragg grating demodulation instrument is connected with the second end of the optical fiber through an optical coupler. The stress monitoring device can overcome the defects that an existing stress monitoring device is prone to electromagnetic interference, large in temperature excursion and poor in environmental adaptability. The utility model further provides a manufacturing method.
Description
Technical field
The present invention relates to a kind of measurement mechanism, particularly relate to a kind of for tying the monitoring device of stress.
Background technology
Current floating hollow panel adopts tether cable to connect the anchoring car on ground more, completes mooring anchoring.The cable that tether cable comprises and optical cable are responsible for respectively providing electric power safeguard from ground to floating hollow panel, and the up-downgoing transmission of control signal is provided.When floating hollow panel is aloft worked, once the power that ties of tether cable declines, can cause floating hollow panel to shake off hawser constraint, cause the major accidents such as spheroid damage out of control, casualties.Therefore must carry out real time on-line monitoring to its mooring stress, to ensure the safety of floating hollow panel.
Between tether cable and floating hollow panel, adopt now piezoelectric type strain gauge to float the pulling force monitoring of hollow panel, adopt piezoelectric type measuring principle, thereby by the monitoring of electric signal being determined to the size of suffered pulling force.In use there is the shortcomings such as zero point drift is large, temperature drift large, poor anti jamming capability in conventional piezoelectric type strain gauge, its output parameter tends to change and generation fluctuation with external environment in time, have a strong impact on acquisition precision and the resolution of data, relative error is larger, when serious, even can provide rub-out signal, cause parameter detecting abnormal, system cannot normally be worked.
There is at present a kind of fiber grating measuring technique, utilize Bragg grating, by the variation to optical grating reflection wavelength, realize the measurement to measured ess-strain.If fiber grating is fixed on response body, when applied stress converts strain to by structure, the strained body stress variable effect of fiber grating, reflection wavelength drifts about, utilize broadband incident light and corresponding fiber grating demodulation equipment just can gather wavelength variation data, just likely realize the corresponding linear measurement of STRESS VARIATION.
There is the methods such as inner wrting method, phase masks in the manufacture of fiber grating, but is subject to technogenic influence, and its structure can't be used for a long time under severe high altitude kite balloon environment.Fiber grating also there will be effect of dispersion under low temperature environment simultaneously, and measuring accuracy is declined.
Summary of the invention
The object of the invention is to improve a kind of monitor for stress, solution cannot utilize fiber grating to carry out the technical matters of effective STRESS VARIATION Real-Time Monitoring.
Another object of the present invention is to provide a kind of manufacture method, and the monitor for stress that ties that solves floating hollow panel tether cable is subject to such environmental effects, technical matters that cannot Measurement accuracy.
Monitor for stress of the present invention, comprises fiber grating, optical fiber and response body, it is characterized in that: on the sidewall of response body, be installed with the protection housing that covers sidewall, on protection housing, offer optical fiber hole, around optical fiber hole, be provided with protection baffle plate; In laying space between protection housing and response body sidewall; the first end of optical fiber is fixed on response body sidewall; axial along response body; also fixing by necessarily twining apart from winding optical fiber on response body sidewall; along optical fiber fiber grating is axially set on optical fiber; the second end of optical fiber stretches out protection housing by optical fiber hole, is connected with wideband incident light source, and fiber Bragg grating (FBG) demodulator connects the second end of optical fiber by photo-coupler.
Described fiber grating comprises the first measuring optical fiber grating and the second measuring optical fiber grating, lays respectively at the monosymmetric position of response body axis.
Described fiber grating also comprises temperature compensation grating, temperature compensation grating, and the first measuring optical fiber grating, the second measuring optical fiber grating forms series connection form.
On described protection housing, offer vertically a rectangular through-hole, protection baffle plate adopts resilient material closely to embed rectangular through-hole, on protection baffle plate, offers optical fiber hole.
Described response body adopts the right cylinder that offers through hole on axis, and its physical dimension is that (φ 60mm ± 1mm) * (120mm ± 1mm), weight are not more than 2kg, and clear size of opening is φ 20mm ± 1mm.
Monitor for stress of the present invention, solves conventional electric transducer and is subject to that electromagnetic interference (EMI), temperature are floated greatly, the poor shortcoming of environmental suitability.Based on optical fiber sensing technology, can realize wide range stress measurement, its maximum stress can reach 200kN, meet the loading stress monitoring requirement of large-scale floating hollow panel, there is the feature that anti-electromagnetic interference (EMI), temperature and zero point drift are little, environmental suitability is strong simultaneously, by adopting optical fiber to carry out stress sensing, its anti-electromagnetic interference capability strengthens greatly, can meet the requirement of GJB151A-97, be not subject to the impact of electromagnetic interference (EMI), its environmental suitability also strengthens greatly simultaneously, under the integrated environments such as the airborne vibration of platform, impact, air pressure, all can accurately carry out the monitoring of parameter.
Innovation passive version, makes product have anti-electrical interference performance, can under strong electromagnetic interference environment, carry out obtaining of data, has solved a difficult problem that is subject to electromagnetic interference (EMI) for existing electric transducer completely.
Employing encapsulates without gel, and the use fiber grating metallization process of innovation is in conjunction with the mode of soldering embedded structure body, has solved the easy fracture that has glue technique to bring, the problem such as come off.
Adopt special package technique, the pre-drawing process of use of innovation solves fiber-optic grating sensor under low temperature environment and easily produces the phenomenon of warbling.
Adopt high precision stress measurement technology, use series connection temperature compensation grating and the double grating averaging method of innovation, solved the impact that the temperature counter stress of sensor is measured, and reduced the impact of eccentric load on measuring accuracy.
The present invention utilizes fiber grating pair tether cable and the suffered stress of assembly to measure, when platform causes the variation of tether cable and the suffered stress of assembly with airflow fluctuation in high-altitude, by obtaining the safety coefficient of working platform to the variation of its stress, when stress exceeds ability to bear meeting and the alarm of tether cable and assembly, thereby guarantee the safe and reliable of floating hollow panel.
The invention solves that original piezoelectric transducer poor anti jamming capability, environmental suitability are poor, temperature floats and the shortcoming such as need repeatedly calibrate greatly, have that range is large, precision is high, corrosion-resistant, anti-electromagnetic interference (EMI), weatherability, long transmission distance, temperature float little feature, further improved the ability to work under floating hollow panel electromagnetic interference environment, expanded the environmental adaptation condition of floating hollow panel, extend the stagnant empty working time of floating hollow panel, for round-the-clock early warning monitors, provide good technical support, there is important multi-field application value.
Below in conjunction with accompanying drawing, embodiments of the invention are described further.
Accompanying drawing explanation
Fig. 1 is the structural representation of monitor for stress of the present invention;
Fig. 2 is the schematic flow sheet of the glue-free packaging technology of fiber grating in monitor for stress of the present invention;
Fig. 3 is the laying mode schematic diagram of fiber grating in monitor for stress of the present invention.
Embodiment
As shown in Figure 1, the present embodiment comprises fiber grating, optical fiber 01 and response body (pressure-bearing body) 04, on the sidewall of response body 04, be installed with the protection housing 05 that covers sidewall, on protection housing 05, offer optical fiber hole 06, around optical fiber hole, be provided with protection baffle plate; In laying space between protection housing 05 and response body 04 sidewall; the first end of optical fiber 01 is fixed on response body sidewall; axial along response body 04; also fixing by necessarily twining apart from winding optical fiber 01 on response body 04 sidewall; along optical fiber 01 fiber grating is axially set on optical fiber; the second end of optical fiber 01 stretches out protection housing 05 by optical fiber hole 06, is connected with wideband incident light source 02, and fiber Bragg grating (FBG) demodulator 03 connects the second end of optical fiber 01 by photo-coupler 07.
In order to adapt to existing mooring structure space, coordinate with tether cable, response body 04 adopts the right cylinder that offers through hole on axis, its physical dimension is that (φ 60mm ± 1mm) * (120mm ± 1mm), assembly weight are not more than 2kg, and clear size of opening is φ 20mm ± 1mm.
In order to ensure mechanical propertys such as vibration, impacts, do the used time and can not produce the phenomenons such as cracking; further strengthen reliability, the resistance to mechanical property of product; can on protection housing 05, offer vertically a rectangular through-hole; protection baffle plate adopts resilient material closely to embed rectangular through-hole, on protection baffle plate, offers optical fiber hole 06.
Fiber Bragg grating (FBG) demodulator 03(fiber grating demodulation device) be positioned at ground anchor and park, for realizing the demodulation process of fiber grating signal, and provide Upper system by the stress signal of measurement, for showing in real time and early warning.The transmission cable being connected with optical fiber adopts nonmetallic materials more protection, selects common flexible optical cable, for the fiber grating of realizing as sensor, is connected with the optical branching device on aerial platform.The present embodiment has solved the poor problem of electromagnetic interference performance that traditional structure brings, and the insulation noiseproof feature that item utilizes optical fiber, has realized monitor for stress passive structures.
Use mucilage sealing to be contained in the fiber grating on optical fiber, because packing forms is subject to high altitude environment influence of temperature change larger, cause longer service time after packaging plastic water stability decline, can cause monitor for stress reliability to reduce, shorten serviceable life.
As shown in Figure 2, in the present embodiment, the encapsulation of fiber grating has adopted following steps:
First, utilize excimer laser by phase mask plate, on optical fiber, to scribe the Fiber Bragg Grating FBG of short distance, the grating wavelength of scribing is 1525nm~1565nm, bandwidth≤0.2nm, grating grid region length≤5mm, the grating of scribing, through high ballast hydrogen, high-temperature annealing process, improves the stability of grating;
Secondly, fiber grating is carried out to surface metalation, utilize electroless plating in conjunction with electric plating method at fiber grating copper coating, step comprises: remove protective seam, oil removing, alligatoring, activation, chemical nickel plating, electro-coppering;
Then, utilize brazing mode that metallized fiber grating on optical fiber and response body 04 is integrally welded.Concrete steps comprise:
Select Sn-4Ag-3Zn solder;
Heating is evenly coated on response body 04 sidewall and metallized fiber grating solder;
Solder Melting And Solidification.
While changing in order further to eliminate low temperature, the chirp phenomenon of lambda1-wavelength, applies prestretched to fiber grating.Concrete steps comprise:
Fiber grating is placed in to response body 04 sidewall and pastes prestretching;
After fixing, heat again solder Melting And Solidification.
Apply prestretching fiber grating afterwards, its contraction can make fiber grating move to short wavelength's direction, as long as guarantee that the wavelength coverage of prestretching can meet the scope that fiber grating is affected by blockage effect, incident light wave there will not be chirp phenomenon.So just avoided the reflection kernel wavelength accuracy that light wave dispersion causes to decline.
As shown in Figure 3, in the present embodiment, in order to realize high precision strain measurement, being wound around on the optical fiber 01 of response body 04, the first measuring optical fiber grating 08 and the second measuring optical fiber grating 09 are set, lay respectively at the response body 04 monosymmetric position of axis, further eliminate in eccentric force process, the discontinuity phenomenon that stress causes, realizes the accuracy requirement of measuring, and forms double grating averaging method and reduces the eccentric load error of calculation.
In manufacturing process, the method that two fiber gratings are together in series, be on response body 04 sidewall, laid the first measuring optical fiber grating 08 after, by winding optical fiber 01, the second measuring optical fiber grating 09 is laid on response body 04 sidewall of response body 04 central axis opposite side, by the variation to the suffered stress in symmetrical side surface, can avoid measuring the appearance of eccentric force error while calculating, in actual test process, also find that eccentric phenomena exists really, if do not measured by double grating, will affect greatly the precision of system.
Also be wound around on the optical fiber 01 of response body 04 set temperature null grating 10 simultaneously.
Traditional temperature subtracts quick mode and adopts the little and temperature-resistant material of thermal expansivity to encapsulate grating, can improve to a great extent the impact of temperature counter stress measurement precision.But this encapsulation will corresponding force measurement selection cause certain limitation, and can not fundamentally remove the impact of temperature, just reduces the factor of influence of temperature, certainly will be also can counter stress measurement data cause certain interference.Based on this, we intend adopting temperature-compensated grating to carry out temperature survey, as the cancellation of temperature impact in stress measurement process.Realize the temperature compensation in stress measurement process.
Temperature compensation grating 10, the first measuring optical fiber grating 08, the second measuring optical fiber gratings 09 form series connection form.
The present embodiment the present invention, by passive pressure-bearing body structure reasonable in design, makes it to meet the stress measurement in electromagnetic interference (EMI) situation, the stress that real-time perception pressure-bearing body bears.By difference packaged fiber grating on the plane of symmetry in pressure-bearing body inside, can realize the eccentrically loaded rejecting of counter stress, guarantee the precision of sensor measurement.In technique, by optical fiber Bragg grating encapsulation is carried out to prestretching, avoid fiber grating to produce chirp phenomenon in environmental fluctuating situation, make product can meet the environmental adaptability of index request, reach higher reliability requirement.
Above-described embodiment is described the preferred embodiment of the present invention; not scope of the present invention is limited; design under the prerequisite of spirit not departing from the present invention; various distortion and improvement that those of ordinary skills make technical scheme of the present invention, all should fall in the definite protection domain of the claims in the present invention book.
Claims (5)
1. a monitor for stress, comprise fiber grating, optical fiber (01) and response body (04), it is characterized in that: on the sidewall of response body (04), be installed with the protection housing (05) that covers sidewall, on protection housing (05), offer optical fiber hole (06), around optical fiber hole, be provided with protection baffle plate; In laying space between protection housing (05) and response body (04) sidewall; the first end of optical fiber (01) is fixed on response body sidewall; axial along response body (04); also fixing by necessarily twining apart from winding optical fiber (01) on response body (04) sidewall; along optical fiber (01) fiber grating is axially set on optical fiber; the second end of optical fiber (01) stretches out protection housing (05) by optical fiber hole (06); be connected with wideband incident light source (02), fiber Bragg grating (FBG) demodulator (03) connects the second end of optical fiber (01) by photo-coupler (07).
2. monitor for stress according to claim 1, is characterized in that: described fiber grating comprises the first measuring optical fiber grating (08) and the second measuring optical fiber grating (09), lays respectively at the monosymmetric position of response body (04) axis.
3. monitor for stress according to claim 2, it is characterized in that: described fiber grating also comprises temperature compensation grating (10), temperature compensation grating (10), the first measuring optical fiber grating (08), the second measuring optical fiber grating (09) forms series connection form.
4. monitor for stress according to claim 3, is characterized in that: on described protection housing (05), offer vertically a rectangular through-hole, protection baffle plate adopts resilient material closely to embed rectangular through-hole, on protection baffle plate, offers optical fiber hole (06).
5. monitor for stress according to claim 4, it is characterized in that: described response body (04) adopts the right cylinder that offers through hole on axis, its physical dimension is that (φ 60mm ± 1mm) * (120mm ± 1mm), weight are not more than 2kg, and clear size of opening is φ 20mm ± 1mm.
Priority Applications (1)
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CN201420087557.9U CN203772461U (en) | 2014-02-27 | 2014-02-27 | Stress monitoring device |
Applications Claiming Priority (1)
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CN201420087557.9U CN203772461U (en) | 2014-02-27 | 2014-02-27 | Stress monitoring device |
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CN203772461U true CN203772461U (en) | 2014-08-13 |
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CN201420087557.9U Expired - Lifetime CN203772461U (en) | 2014-02-27 | 2014-02-27 | Stress monitoring device |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103837273A (en) * | 2014-02-27 | 2014-06-04 | 中国电子科技集团公司第八研究所 | Stress monitoring device and manufacturing method |
CN111426411A (en) * | 2020-05-11 | 2020-07-17 | 浙江大学 | Multi-scale flexible light-sensitive mechanical pressure sensor |
-
2014
- 2014-02-27 CN CN201420087557.9U patent/CN203772461U/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103837273A (en) * | 2014-02-27 | 2014-06-04 | 中国电子科技集团公司第八研究所 | Stress monitoring device and manufacturing method |
CN111426411A (en) * | 2020-05-11 | 2020-07-17 | 浙江大学 | Multi-scale flexible light-sensitive mechanical pressure sensor |
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Granted publication date: 20140813 |