CN108801216A - A kind of fiber bragg grating inclinator - Google Patents
A kind of fiber bragg grating inclinator Download PDFInfo
- Publication number
- CN108801216A CN108801216A CN201810437573.9A CN201810437573A CN108801216A CN 108801216 A CN108801216 A CN 108801216A CN 201810437573 A CN201810437573 A CN 201810437573A CN 108801216 A CN108801216 A CN 108801216A
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- China
- Prior art keywords
- fiber
- shell
- optical fiber
- bragg grating
- fiber bragg
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C9/00—Measuring inclination, e.g. by clinometers, by levels
- G01C9/10—Measuring inclination, e.g. by clinometers, by levels by using rolling bodies, e.g. spheres, cylinders, mercury droplets
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C9/00—Measuring inclination, e.g. by clinometers, by levels
- G01C9/10—Measuring inclination, e.g. by clinometers, by levels by using rolling bodies, e.g. spheres, cylinders, mercury droplets
- G01C2009/107—Measuring inclination, e.g. by clinometers, by levels by using rolling bodies, e.g. spheres, cylinders, mercury droplets spheres
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Light Guides In General And Applications Therefor (AREA)
Abstract
The invention discloses a kind of fiber bragg grating inclinators, belong to technical field of optical fiber sensing.Including shell, through-hole bolt, pedestal, bolt, the beam of uniform strength, connecting rod, mass ball, fiber grating, optical fiber, fiber coupler, tail optical fiber protective case and tail optical fiber；Shell appearance is cuboid, and inside is a cavity, and shell one end opens up a certain size internal thread through hole, is connect with through-hole bolt thread, and the other end is bolted with pedestal, and pedestal is detachable.Enclosure interior cavity wall is fixed with the beam of uniform strength, and the beam of uniform strength other end is connected with connecting rod, and connecting rod connects a mass ball, and mass ball is contacted with cavity wall surrounding, can be slidably reciprocated.Bottom surface symmetrically pastes fiber grating on the beam of uniform strength, and two fiber gratings are coupled to by fiber coupler on an optical fiber, reconnects tail optical fiber and passes through through-hole bolt.
Description
Technical field
The present invention relates to a kind of fiber bragg grating inclinators, especially a kind of to be used for real time on-line monitoring object inclination angle
Fiber bragg grating inclinator.Belong to technical field of optical fiber sensing.
Background technology
Civil engineering, science of bridge building, coal mine, oil field, the various fields such as Aerospace Engineering, mechanical engineering are not all from
The measurement at inclination angle is opened, for example, sensor is mounted on the amount of deflection or settlement of foundation of bridge or road surface for measuring bridge；Installation
On mechanical rocking arm, monitoring rocking arm runs posture, for example obliquity sensor is applied to the boarding ladder of aircraft, or by inclination angle
Sensor application is on rocker arm of coal mining machine.Traditional obliquity sensor is based substantially on electromagnetic sensing principle, can realize inclination angle essence
The requirement really monitored, but such sensor is under forceful electric power, magnetic environment, as working condition becomes in the coal working face in coal mine
Difference is unfavorable for transmission and distributed measurement etc. at a distance.
Invention content
Technical problem：It is an object of the present invention to for above-mentioned traditional electromagnetism class obliquity sensor there are the problem of, propose
A kind of fiber bragg grating inclinator is used for the inclination angle of real time on-line monitoring object.
Technical solution：The front end of a kind of fiber bragg grating inclinator of the present invention, including shell, shell is equipped with through-hole
The rear end of bolt, shell is equipped with pedestal, and the tail optical fiber stretched out outside through-hole bolt port, institute are equipped in the through-hole of the through-hole bolt
It states and is equipped with the beam of uniform strength in front of the inside of shell, the inside rear of shell is equipped with mass ball, and the beam of uniform strength is equipped with and acts against matter
The connecting rod on ball is measured, symmetrically pastes that there are two fiber grating, two fiber gratings before and after the beam of uniform strength on the center line of bottom surface
Through fiber coupler together with fiber coupling, and it is connected with tail optical fiber.
The shell is cuboid, and inside is a cavity, and the front end of shell is provided with and the matched interior spiral shell of through-hole bolt
Line through-hole.
The mass ball is contacted with shell cavity wall surrounding, for dynamic cooperation, can be slidably reciprocated.
The enclosure interior cavity wall polishes smooth, and coats lubricant.
The mass ball is shot.
The fiber grating initial center wavelength is equal.
The tail optical fiber is internally provided with tail optical fiber protective case in through-hole bolt.
The pedestal is bolted on shell.
Advantageous effect：Since fiber bragg grating obliquity sensor is not by electromagnetic interference, it can delicately reflect object
Athletic posture changes the linear relationship between the variation of back rake angle and fiber bragg grating center wavelength variation, according to wavelength-division multiplex skill
Art, the Distributed Multi that fiber Bragg grating sensor may be implemented measures and remote transmission, applied widely, and is applicable in
In coal mine.The fiber-optic grating sensor that the present invention uses can realize long-term real time on-line monitoring, be easy to composition and measure network,
Compared with traditional sensors, have the following advantages that：(1) high sensitivity, anti-electromagnetic interference capability are strong, corrosion-resistant, are suitably applied
Adverse circumstances；(2) it deploys to ensure effective monitoring and control of illegal activities convenient for networking, using wavelength-division multiplex, time division multiplexing, space division multiplexing or is used in combination, may be implemented
The multimetering of large area；(3) small, light weight is easy to be embedded to inside configuration, monitoring of structures internal stress strain variation；
(4) it is convenient for data information acquisition, facilitates transmission etc..It can be used for accurately measuring object inclination angle, high sensitivity, anti-electromagnetic interference capability
By force, corrosion-resistant, adverse circumstances are suitably applied, compared with the prior art, major advantage has：
(1) simple in structure, easy for installation, high sensitivity, anti-electromagnetic interference capability is strong, corrosion-resistant, is suitably applied severe
Environment；
(2) advanced fiber grating sensing technology is utilized, convenient for remote and 24 hours monitor on-line, data is facilitated to acquire
With storage；
(3) influence of temperature error is eliminated.
Description of the drawings
Fig. 1 is the internal structure schematic diagram of apparatus of the present invention；
Fig. 2 is the left view of apparatus of the present invention；
Fig. 3 is the right view of apparatus of the present invention；
Fig. 4 is fiber grating paste position schematic diagram in apparatus of the present invention.
Figure label：1, shell；2, through-hole bolt；3, pedestal；4, bolt；5, the beam of uniform strength；6, connecting rod；7, quality
Ball；8, fiber grating；9, optical fiber；10, fiber coupler；11, tail optical fiber protective case；12, tail optical fiber
Specific implementation mode
The invention will be further described for middle embodiment below in conjunction with the accompanying drawings：
As shown in Figure 1,2 and 3, fiber bragg grating inclinator of the invention, mainly by shell 1, through-hole bolt 2, bottom
Seat 3, bolt 4, the beam of uniform strength 5, connecting rod 6, mass ball 7, fiber grating 8, optical fiber 9, fiber coupler 10, tail optical fiber protective case 11
It is constituted with tail optical fiber 12.The shell 1 is cuboid, and inside is a cavity, and the front end of shell 1 is provided with to match with through-hole bolt 2
The internal thread through hole of conjunction.The front end of the shell 1 is equipped with through-hole bolt 2, and the rear end of shell 1 is equipped with pedestal 3, and pedestal 3 is by bolt 4
It is fixed on shell 1, detachably.The tail optical fiber 12 stretched out outside through-hole bolt port, tail are equipped in the through-hole of the through-hole bolt 2
Fibre 12 is internally provided with tail optical fiber protective case 11 in through-hole bolt 2.The beam of uniform strength 5 is equipped in front of the inside of the shell 1, shell 1
Internal rear is equipped with mass ball 7, and mass ball 7 is shot.Mass ball 7 is contacted with shell cavity wall surrounding, for dynamic cooperation, can be slided back and forth
It is dynamic.1 inside cavity wall of shell polishes smooth, and coats lubricant.The beam of uniform strength 5 is equipped with the connecting rod 6 being connected on mass ball 7,
7 ball of quality can cooperate with sliding, and beam of uniform strength bending is driven by connecting rod 6；It is right on the center line of bottom surface before and after the beam of uniform strength 5
Claim to paste there are two fiber grating 8, i.e. fiber grating 8 is pasted onto in 5 central symmetry axes of the beam of uniform strength, and fiber grating 8 is initial
Centre wavelength is equal.Two fiber gratings 8 connect fiber coupler 10 through optical fiber 9 respectively, and fiber coupler 10 is coupled with optical fiber 9
Together, and with tail optical fiber 12 it is connected, tail optical fiber 12 passes through through-hole bolt 2.
When work, by 12 incoming fiber optic (FBG) demodulator channel of tail optical fiber, the centre wavelength of two fiber gratings 8 is demodulated, incite somebody to action this
Fiber bragg grating inclinator is placed on testee, and when 1 run-off the straight of shell, shell 1 generates one relative to horizontal position
A inclination angle Δ θ, the center wavelength shift of two fiber gratings 8 calculate the sum of center wavelength shift amount, substitute into formula (1), you can
Instrument angle of inclination is obtained, to eliminate the influence of temperature error.Detailed process is as follows：
When lower section or the upper right side run-off the straight to the left of shell 1, shell 1 relative to horizontal position there are an inclination angle Δ θ, this
When, the beam of uniform strength 6 is bending to the left, left side fiber grating compression force effect, and centre wavelength reduces, and shows wave crest to the left in (FBG) demodulator
Offset, center wavelength shift amount are Δ λB1, by pulling force effect, centre wavelength increases right side fiber grating, and wave is shown in (FBG) demodulator
Peak deviates to the right, and center wavelength shift amount is Δ λB2,
When shell 1 is to upper left side or lower right run-off the straight, at this point, the beam of uniform strength 6 is bending to the right, left side fiber grating by
Pulling force effect, centre wavelength increase, and show that wave crest deviates to the right in (FBG) demodulator, and center wavelength shift amount is Δ λ 'B1, right side optical fiber
Grating compression force effect, centre wavelength reduce, and show that wave crest deviates to the left in (FBG) demodulator, and center wavelength shift amount is Δ λ 'B2。
The sum of two center wavelength shift amounts Δ λB1+ΔλB2(or Δ λ 'B1+Δλ'B2) there are following relationships with inclination angle Δ θ：
In formula：The length of the L- beam of uniform strengths, the b- beam of uniform strengths are in the width of fixing end, the thickness and material of the h- beam of uniform strengths
Material, the elasticity modulus of the E- beam of uniform strengths；λBFor fiber grating initial wavelength；PeFor the elasto-optical coefficient of optical fiber；M is the matter of mass ball
Amount.
Claims (8)
1. a kind of fiber bragg grating inclinator, it is characterised in that：It includes shell（1）, shell（1）Front end be equipped with through-hole
Bolt（2）, shell（1）Rear end be equipped with pedestal（3）, the through-hole bolt（2）Through-hole in be equipped with stretch out through-hole bolt end
Tail optical fiber outside mouthful（12）, the shell（1）Inside in front of be equipped with the beam of uniform strength（5）, shell（1）Inside rear be equipped with quality
Ball（7）, the beam of uniform strength（5）It is equipped with and acts against mass ball（7）On connecting rod（6）, the beam of uniform strength（5）The center of front and back bottom surface
Fiber grating there are two symmetrically being pasted on line（8）, two fiber gratings（8）Through fiber coupler（10）With optical fiber（9）It is coupling in
Together, and and tail optical fiber（12）It is connected.
2. fiber bragg grating inclinator according to claim 1, it is characterised in that：The shell（1）It is rectangular
Body, inside are a cavity, shell（1）Front end be provided with and through-hole bolt（2）Matched internal thread through hole.
3. fiber bragg grating inclinator according to claim 1, it is characterised in that：The mass ball（7）With shell
Body（1）Cavity wall surrounding contacts, and for dynamic cooperation, can slidably reciprocate.
4. fiber bragg grating inclinator according to claim 1, it is characterised in that：The shell（1）Inner chamber
Wall polishes smooth, and coats lubricant.
5. fiber bragg grating inclinator according to claim 1, it is characterised in that：The mass ball（7）For lead
Ball.
6. fiber bragg grating inclinator according to claim 1, it is characterised in that：The fiber grating（8）Just
Beginning centre wavelength is equal.
7. fiber bragg grating inclinator according to claim 1, it is characterised in that：The tail optical fiber（12）In through-hole
Bolt（2）It is internally provided with tail optical fiber protective case（11）.
8. fiber bragg grating inclinator according to claim 1, it is characterised in that：The pedestal（3）By bolt
（4）It is fixed on shell（1）On.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810437573.9A CN108801216A (en) | 2018-05-09 | 2018-05-09 | A kind of fiber bragg grating inclinator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810437573.9A CN108801216A (en) | 2018-05-09 | 2018-05-09 | A kind of fiber bragg grating inclinator |
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| Publication Number | Publication Date |
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| CN108801216A true CN108801216A (en) | 2018-11-13 |
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ID=64092139
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| CN201810437573.9A Pending CN108801216A (en) | 2018-05-09 | 2018-05-09 | A kind of fiber bragg grating inclinator |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113029427A (en) * | 2021-03-15 | 2021-06-25 | 中国矿业大学 | Mine wind pressure measuring device, mine wind pressure detecting system and mine wind pressure detecting method based on fiber bragg grating |
| CN113137928A (en) * | 2020-12-10 | 2021-07-20 | 中铁二院工程集团有限责任公司 | Deep rock-soil body optical fiber inclination measuring system based on optical frequency domain reflection technology |
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| US20030071202A1 (en) * | 2001-10-15 | 2003-04-17 | Ames Gregory H. | Fiber optic pitch or roll sensor |
| CN1635335A (en) * | 2003-12-29 | 2005-07-06 | 卓越光纤股份有限公司 | Optical fiber inclinometer |
| CN2738479Y (en) * | 2004-11-09 | 2005-11-02 | 李小路 | Rail monitoring system based on wave divided multiplex distribution type optical fibre |
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| CN103454021A (en) * | 2013-08-15 | 2013-12-18 | 中国矿业大学 | Tunnel surrounding rock stress monitoring device based on fiber grating sensing |
| CN204740026U (en) * | 2015-07-16 | 2015-11-04 | 杭州聚华光电科技有限公司 | Fiber grating clinometer |
| TW201716746A (en) * | 2015-11-04 | 2017-05-16 | Nat Kaohsiung First Univ Of Science And Tech | Building inclination detector having a simple structure and high accuracy |
| CN107131878A (en) * | 2017-07-11 | 2017-09-05 | 中国矿业大学 | A kind of rocker arm of coal mining machine pose monitoring device and method based on fiber grating |
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2018
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| US5428219A (en) * | 1994-04-06 | 1995-06-27 | United States Of America As Represened By The United States Department Of Energy | Fiber optic inclination detector system having a weighted sphere with reference points |
| FR2807512B1 (en) * | 2000-04-11 | 2002-05-24 | Commissariat Energie Atomique | BRAGG NETWORK INCLINOMETER |
| US20030071202A1 (en) * | 2001-10-15 | 2003-04-17 | Ames Gregory H. | Fiber optic pitch or roll sensor |
| CN1635335A (en) * | 2003-12-29 | 2005-07-06 | 卓越光纤股份有限公司 | Optical fiber inclinometer |
| CN2738479Y (en) * | 2004-11-09 | 2005-11-02 | 李小路 | Rail monitoring system based on wave divided multiplex distribution type optical fibre |
| CN101038297A (en) * | 2006-02-15 | 2007-09-19 | Pgs地球物理公司 | Pressure compensated optical accelerometer, optical inclinometer and seismic sensor system |
| JP2009058239A (en) * | 2007-08-30 | 2009-03-19 | Tobishima Corp | Fbg optical fiber sensor type clinometer |
| CN101387516A (en) * | 2008-10-23 | 2009-03-18 | 曹春耕 | Optical fibre grating inclinometer |
| CN101540468A (en) * | 2009-04-20 | 2009-09-23 | 浙江大学 | Method and devices for optically generating high-frequency microwave signals |
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| CN203231733U (en) * | 2013-03-25 | 2013-10-09 | 中铁二院工程集团有限责任公司 | Stay rope type fiber grating displacement sensor |
| CN103398800A (en) * | 2013-07-20 | 2013-11-20 | 北京航空航天大学 | Quasi-distributed fiber bragg grating temperature stress measuring system for large-size structure body |
| CN103454021A (en) * | 2013-08-15 | 2013-12-18 | 中国矿业大学 | Tunnel surrounding rock stress monitoring device based on fiber grating sensing |
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| TW201716746A (en) * | 2015-11-04 | 2017-05-16 | Nat Kaohsiung First Univ Of Science And Tech | Building inclination detector having a simple structure and high accuracy |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113137928A (en) * | 2020-12-10 | 2021-07-20 | 中铁二院工程集团有限责任公司 | Deep rock-soil body optical fiber inclination measuring system based on optical frequency domain reflection technology |
| CN113137928B (en) * | 2020-12-10 | 2024-01-19 | 中铁二院工程集团有限责任公司 | Deep rock-soil body optical fiber inclinometry system based on optical frequency domain reflection technology |
| CN113029427A (en) * | 2021-03-15 | 2021-06-25 | 中国矿业大学 | Mine wind pressure measuring device, mine wind pressure detecting system and mine wind pressure detecting method based on fiber bragg grating |
| CN113029427B (en) * | 2021-03-15 | 2022-03-01 | 中国矿业大学 | Mine wind pressure measuring device, mine wind pressure detecting system and mine wind pressure detecting method based on fiber bragg grating |
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