CN106840486B - Full distributed Dedenda's bending stress device for dynamically detecting and method - Google Patents

Full distributed Dedenda's bending stress device for dynamically detecting and method Download PDF

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CN106840486B
CN106840486B CN201710014460.3A CN201710014460A CN106840486B CN 106840486 B CN106840486 B CN 106840486B CN 201710014460 A CN201710014460 A CN 201710014460A CN 106840486 B CN106840486 B CN 106840486B
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coupler
polarization
photodetector
optical
output end
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CN106840486A (en
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李政颖
王凡
徐刚
王洪海
桂鑫
向娜
刘佳佩
耿彪
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Wuhan University of Technology WUT
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Wuhan University of Technology WUT
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
    • G01L1/242—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre
    • G01L1/246—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre using integrated gratings, e.g. Bragg gratings
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/26—Auxiliary measures taken, or devices used, in connection with the measurement of force, e.g. for preventing influence of transverse components of force, for preventing overload

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  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

The present invention relates to a kind of full distributed Dedenda's bending stress device for dynamically detecting and method, it includes frequency swept laser, optical splitter C1, optical splitter C2, coupler C3, coupler C4, polarization-maintaining photo-coupler C5, coupler C6, analyzer A1, analyzer A2, photodetector D1, photodetector D2, photodetector D3, photodetector D4, optical circulator, fiber rotation connector, time delay optical fiber, wavelength calibration tool, isolator, processor, the polarization-maintaining fiber grating being axially attached to along Gear Root in Gear Root.The present invention can be with the bending stress of Real-time and Dynamic Detection each point at Gear Root, and accuracy rate is high, spatial resolution with higher, and structure is simple, does not interfere vulnerable to extraneous factors such as temperature, electromagnetism.

Description

Full distributed Dedenda's bending stress device for dynamically detecting and method
Technical field
The present invention relates to fiber grating Dedenda's bending stress detection technique fields, and in particular to a kind of full distributed tooth root is curved Transverse stress device for dynamically detecting and method.
Background technique
In fields such as automobile, agricultural machinery, transmission, industry, gear has relatively broad application, has and is driven where all It is unable to do without various gear combinations.And the failure of tooth root flexural fatigue is to influence one of the important behaviour form of gear performance, so smart Really and in real time the bending stress of detection Gear Root everywhere is significantly.(length is big for overlength polarization-maintaining fiber grating In 10cm) there is many good characteristics such as flexible, insertion loss is small, stress applied area and covering in polarization-maintaining fiber grating structure Between thermal expansion coefficient there are difference so that there are stress birfringence phenomenons for grating, due to the presence of birefringent phenomenon, grating For reflectance spectrum there are two kinds of polarization states, such overlength polarization-maintaining fiber grating can be equivalent at two common long gratings, and two The influence of stress suffered by root grating and temperature is identical, but response characteristic is different, and because of the overlength optical fiber raster grid period It is short and grid region length is long, therefore can be segmented into and formed by multiple short grating alignments.After incident light injects short grating, meet its cloth The light of glug wavelength can reflect, and when short grating is acted on by extraneous stress, the variation of pitch and refractive index can be led Wherein heart wave length shift is caused, so the variation of suffered stress can be embodied from the variation of its central wavelength.Therefore pass through The modulated signal of two kinds of polarization states corresponding to overlength polarization-maintaining fiber grating carries out staged demodulation, and carries out decoupling processing respectively The strain of its corresponding points, spatial resolution with higher and accuracy can be obtained with the influence of compensation temperature.
Currently, the calculating of Dedenda's bending stress or detection method mainly have FInite Element, based on the strength of gear teeth of national standard Calculation method and electrical measuring method etc..Such as traditional strain ga(u)ge measuring technology, answering for a metal material is sticked at Gear Root Become piece, under ambient pressure effect, the resistance of foil gauge changes, and solves this by the resistance variations of measurement strain front and back Place's strain, to obtain bending stress size at it, but the method has some defects, for example the foil gauge used is metal material Material, metal material can be influenced by many extraneous factors, and it can only measure the average bending stress at Gear Root, cannot Branch measurement；For another example the measurement method of Chinese patent CN104101380A planetary gear train fixed center Gear Root Stress strain, It is to have multiple Bragg gratings on probe by installing raster probe at central gear root fillet, before demodulation strain The drift value of each raster center wavelength calculates its stress afterwards, and the defect of the method is mainly that common grating length itself about exists 1cm or so, and gear width is comparatively very limited, so can only install several gratings on a tooth root, therefore this method is also only It is capable of measuring the bending stress of a few point, there is limitation, the bending that in addition this method can only also measure on facewidth direction is answered Power cannot achieve the bending stress measurement on the high direction of the flexure planes tooth such as spiral bevel gear；There are also Chinese patents A kind of method for instructing gear stress mornitoring and root stress to analyze that CN105404738A is proposed, is used by ANSYS The gear for the ring gear part that Static Method and 3D modeling software Pro/E pair are engaged with single planetary gear is analyzed, and tooth is extracted The information such as root stress and distribution, but the method process is more complicated, can not achieve and real-time dynamicly measures, and finally obtained It is the maximum value of tooth root equivalent stress, so detecting Dedenda's bending stress in unsuitable practical application.
Summary of the invention
The purpose of the present invention is to provide a kind of full distributed Dedenda's bending stress device for dynamically detecting and method, the devices It is detected with method using overlength polarization-maintaining fiber grating and is strained at tooth root, its corresponding modulated signal of two kinds of polarization states is divided Section processing, and decoupled and interfered with compensation temperature, the limitation of general grating length is breached, accuracy rate is high, and has high-altitude Between resolution ratio, the high speed frequency swept laser in used demodulating system ensure that the real-time of detection, passes through a series of amendments Calibration and compensation method accurately demodulate overlength polarization-maintaining fiber grating spectral drift under two kinds of polarization states everywhere, after decoupling processing The stress of its corresponding points is obtained, to realize the full distributed Real-time and Dynamic Detection to Gear Root bending stress everywhere.
In order to solve the above technical problems, a kind of full distributed Dedenda's bending stress device for dynamically detecting disclosed by the invention, It includes frequency swept laser, optical splitter C1, optical splitter C2, coupler C3, coupler C4, polarization-maintaining photo-coupler C5, coupling Device C6, analyzer A1, analyzer A2, photodetector D1, photodetector D2, photodetector D3, photodetector D4, light Circulator, time delay optical fiber, wavelength calibration tool, isolator, processor, along Gear Root is axially attached to tooth at fiber rotation connector Take turns the polarization-maintaining fiber grating on tooth root, wherein the swept-frequency signal output end connection optical splitter C1's of the frequency swept laser is defeated Enter end, the input terminal of the first output end connection optical splitter C2 of optical splitter C1, the second output terminal of optical splitter C1 passes through Isolator connects the input terminal of coupler C3, the input terminal of the first output end connection coupler C4 of optical splitter C2, optical branching The input terminal of the second output terminal connection wavelength calibration tool of device C2, the input of the first output end connection coupler C6 of coupler C4 End, the second output terminal of coupler C4 connect the input terminal of coupler C6, the output end connection of coupler C6 by time delay optical fiber The input terminal of photodetector D1, the input terminal of the output end connection photodetector D2 of wavelength calibration tool, the of coupler C3 One output end connects the input terminal of polarization-maintaining photo-coupler C5, and the first of the second output terminal connection optical circulator of coupler C3 connects Mouthful, the fixing end connection jaws of the second interface connection fiber rotation connector of optical circulator, the round end of fiber rotation connector Connection jaws connect one end of polarization-maintaining fiber grating, and the input terminal of the third interface connection polarization-maintaining photo-coupler C5 of optical circulator is protected The first output end of polarisation coupler C5 passes through the input terminal of analyzer A1 connection photodetector D3, polarization-maintaining photo-coupler C5's Second output terminal passes through the input terminal of analyzer A2 connection photodetector D4, photodetector D1, photodetector D2, photoelectricity The signal output end of detector D3 and photodetector D4 are all connected with the signal input part of processor.
A kind of full distributed Dedenda's bending stress dynamic testing method using above-mentioned apparatus, which is characterized in that it includes Following steps:
Step 1: tested gear is placed in stationary state；
Step 2: frequency swept laser issues sweeping laser, which enters optical splitter C1；
Step 3: the first output end output amendment channel sweeping laser signal of optical splitter C1, the second of optical splitter C1 Output end exports Measurement channel sweeping laser signal；
Step 4: the amendment channel sweeping laser signal in step 3 enters optical splitter C2 and is divided into two beam sweeping lasers；Step Measurement channel sweeping laser signal enters coupler C3 after isolator (9) and is divided into two beam sweeping lasers in rapid 3；
Step 5: the sweeping laser of the first output end of optical splitter C2 output enters coupler C4, and the first of coupler C4 The sweeping laser of output end output is directly entered the input terminal of coupler C6, and the frequency sweep of the second output terminal output of coupler C4 swashs Light enters the input terminal of coupler C6, and the sweeping laser with the output of the first output end of coupler C4 after time delay optical fiber 7 Photo-beat phenomenon is generated in coupler C6, the beat signal of photodetector D1 acquisition coupler C6 output is simultaneously converted into corresponding Electric signal；
The sweeping laser of the second output terminal output of optical splitter C2 is filtered by wavelength calibration tool, photodetector The optical signal of D2 acquisition wavelength calibration tool output is simultaneously converted into corresponding electric signal；
The sweeping laser of the first output end output of coupler C3 is directly entered polarization-maintaining photo-coupler C5；The of coupler C3 The sweeping laser of two output ends output enters the polarization-maintaining fiber grating being affixed in Gear Root, and polarization-maintaining fiber grating reflects two kinds The laser signal of polarization state, the laser signal of above two polarization state enter polarization-maintaining photo-coupler C5, and the first of coupler C3 is defeated The sweeping laser of outlet output and the laser signal of above two polarization state generate photo-beat, polarization-maintaining light in polarization-maintaining photo-coupler C5 The beat signal of coupler C5 output is respectively enterd by the beat frequency light that analyzer A1 and analyzer A2 isolate two kinds of polarization states Photodetector D3 and photodetector D4, photodetector D1, photodetector D2, photodetector D3 and photodetector After D4 converts electric signal for the optical signal detected respectively, it is transferred to processor；
Step 6: the electric signal obtained in the processor with photodetector D1 is to photodetector D2, photodetector D3 Interpolation resampling is carried out with the obtained electric signal of photodetector D4, to compensate the nonlinear effect of frequency swept laser；It is handling The electric signal obtained in device with photodetector D2 is modified the sweep velocity of frequency swept laser；In the processor to photoelectricity The electric signal that detector D2 and photodetector D3 are obtained carries out staged demodulation processing respectively, obtains respectively solving on polarization-maintaining fiber grating Adjust wavelength of the segmentation under two kinds of polarization states；Processor decouples the wavelength under two kinds of obtained polarization states, eliminates temperature Influence to testing result obtains the initial wavelength λ of each staged demodulation section on polarization-maintaining fiber grating under above two polarization statei, Initial wavelength λiFor be tested gear stationary when polarization-maintaining fiber grating on each staged demodulation section wavelength；
Step 7: in the rotation of tested gear, obtaining being tested gear under above two polarization state according to the step of step 2~6 When movement on polarization-maintaining fiber grating each staged demodulation section wavelength, and find out under two kinds of polarization states be tested gear stationary and movement shape Each staged demodulation section wavelength difference Δ λ of state, staged demodulation section wavelength difference Δ λ are only strained influence；
Step 8: processor calculates strain stress suffered by each staged demodulation section of polarization-maintaining fiber grating according to the following formulai；
Δ λ=(1-P) λiεi
Wherein, P is effective strain optical coefficient of polarization-maintaining fiber grating, εiTo be answered suffered by each staged demodulation section of polarization-maintaining fiber grating Become, when calculating, Δ λ and λiArbitrarily select the value under the same polarization state；
Then, by each staged demodulation section of polarization-maintaining fiber grating institute it is strained according to recklessly can law obtain corresponding real-time tooth Root distribution bending stresses.
The present invention sticks a root long degree at Gear Root and the overlength polarization-maintaining fiber grating of Gear Root equivalent width is (long Degree is greater than 10cm).Compared with common overlength optical fiber grating, there are stress birfringence phenomenons in overlength polarization-maintaining fiber grating, anti- There are two different polarization states for ejected wave, thus its can it is equivalent at two under the identical environment but that response characteristic is different is super Long optical fibers grating；Compared with ordinary optic fibre grating, overlength optical fiber grating grid region length is long, and reflection bandwidth is wide, ordinary optic fibre grating Grid region length generally only has several millimeters；Compared with long-period fiber grating, it is reflection type optical that the overlength optical fiber raster grid period is short Grid, and long-period fiber grating grid cycle is generally several hundred microns, belongs to transmission-type grating.Just because of overlength polarization maintaining optical fibre Grating is there are birefringent phenomenon, and there are two kinds of polarization states for reflected light, therefore it equivalent can be in equal ambient at two Lower but different response characteristic overlength optical fiber grating, and overlength optical fiber grating grid region distance is very long, and grid cycle is short, therefore its It equivalent can be formed again at multiple short grating alignments,
Each short grating can reflect the light wave of specific wavelength.Due to it is equivalent at each of short grating length very little, when by When to external stress, it is believed that Strain Distribution is uniform on each short grating.In the present invention, equivalent short light may be implemented Gate length is 1mm, it means that the spatial resolution of detection device can achieve 1mm.
If tiFor light on overlength optical fiber grating by it is equivalent at i-th of FBG reflect caused by time delay, then it is each equivalent FBG reflection light all can with polarization-maintaining controller issue light photo-beat, and each equivalent FBG are generated at polarization-maintaining coupler Generated corresponding photo-beat has unique frequency γvti, wherein γvFor the sweep rate of high speed frequency swept laser.
What two photodetectors of measurement module detected be respectively overlength polarization-maintaining fiber grating it is equivalent at two it is general On logical overlength optical fiber grating it is all it is equivalent at short FBG and the light that issues of the polarization-maintaining controller beat signal that generates in the time domain Superposition, can be such that they separate on frequency domain by carrying out FFT transform to it, then utilize the rectangular window of suitable width Filter segmentation chooses the corresponding frequency-region signal of corresponding each equivalent FBG and carries out IFFT transformation to obtain the equivalent FBG Signal in the time domain obtains its envelope with Hilbert transform and seeks each equivalent FBG acquisition time domain with Gauss curve fitting The time point of peak value.The effect of calibration module and the reference module is calibration output wavelength and compensation system nonlinear effect respectively. In this way, demodulating system can find out the reflection wavelength of tooth root bending front and back overlength polarization-maintaining fiber grating two kinds of polarization states everywhere respectively Drift value, since optic fiber grating wavelength drift is temperature and strain being superimposed of having an impact, and the grating institute under two kinds of polarization states By temperature and strain influenced be as, therefore carrying out decoupling reprocessing to the wavelength shift under two kinds of polarization states can be with The influence of temperature is eliminated, the wave length shift of only strained influence is obtained.It can be quasi- in conjunction with stress sensing model and Hooke's law Really calculate corresponding point position Dedenda's bending stress.
High speed frequency swept laser used in demodulating system of the invention can be more in designated band in a short time Secondary scanning makes system can the bending stress variation at Gear Root with real-time dynamic monitoring.
Beneficial effects of the present invention:
The bending stress at tooth root is sensed using polarization-maintaining fiber grating, by the non-thread of high speed frequency swept laser Property frequency sweep compensate and its sweep rate be modified, and to overlength polarization-maintaining fiber grating at Gear Root two kinds partially The equivalent FBG in arbitrary point can be with compensation temperature to testing result after the wave length shift before and after strain is decoupled under polarization state Influence, in conjunction with stress sensing model and Hooke's law, can with the bending stress of Real-time and Dynamic Detection each point at Gear Root, Accuracy rate is high, spatial resolution with higher, and structure is simple, does not interfere vulnerable to extraneous factors such as temperature, electromagnetism.
Detailed description of the invention
Fig. 1 is the overlength polarization-maintaining fiber grating schematic diagram used in the present invention；
Fig. 2 is that overlength polarization-maintaining fiber grating pastes schematic diagram in the present invention；
Fig. 3 is the device of the invention structure chart.
Wherein, 1-frequency swept laser, 2-processors, 3-optical circulators, 4-fiber rotation connectors, 5-gear teeth Root, 6-polarization-maintaining fiber gratings, 7-time delay optical fibers, 8-wavelength calibrations tool, 9-isolators.
Specific embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail:
A kind of full distributed Dedenda's bending stress device for dynamically detecting of the invention, as shown in Figures 1 to 3, it includes frequency sweep Laser 1, optical splitter C1, optical splitter C2, coupler C3, coupler C4, polarization-maintaining photo-coupler C5, coupler C6, analyzing Device A1, analyzer A2, photodetector D1, photodetector D2, photodetector D3, photodetector D4, optical circulator 3, Fiber rotation connector 4, time delay optical fiber 7, wavelength calibration have 8, isolator 9, processor 2, are axially attached to gear along Gear Root 5 Polarization-maintaining fiber grating 6 on tooth root 5, wherein the swept-frequency signal output end connection optical splitter C1's of the frequency swept laser 1 is defeated Enter end, the input terminal of the first output end connection optical splitter C2 of optical splitter C1, the second output terminal of optical splitter C1 passes through Isolator 9 connects the input terminal of coupler C3, the input terminal of the first output end connection coupler C4 of optical splitter C2, optical branching The input terminal of the second output terminal connection wavelength calibration tool 8 of device C2, the first output end connection coupler C6's of coupler C4 is defeated Enter end, the second output terminal of coupler C4 connects the input terminal of coupler C6 by time delay optical fiber 7, and the output end of coupler C6 connects The input terminal of photodetector D1 is connect, the output end of wavelength calibration tool 8 connects the input terminal of photodetector D2, coupler C3's First output end connects the input terminal of polarization-maintaining photo-coupler C5, and the second output terminal of coupler C3 connects the first of optical circulator 3 Interface, the fixing end connection jaws of the second interface connection fiber rotation connector 4 of optical circulator 3, the rotation of fiber rotation connector 4 Turn one end of terminated line mouth connection polarization-maintaining fiber grating 6, the input of the third interface connection polarization-maintaining photo-coupler C5 of optical circulator 3 End, the first output end of polarization-maintaining photo-coupler C5 pass through the input terminal of analyzer A1 connection photodetector D3, polarization-maintaining optical coupling The second output terminal of device C5 passes through the input terminal of analyzer A2 connection photodetector D4, photodetector D1, photodetector The signal output end of D2, photodetector D3 and photodetector D4 are all connected with the signal input part of processor 2.
In above-mentioned technical proposal, the first output end of the optical splitter C1 and the splitting ratio of second output terminal are 1:99, The first output end of optical splitter C2 and the splitting ratio of second output terminal are 1:1.
In above-mentioned technical proposal, the length of the polarization-maintaining fiber grating 6 is equal to the axial length of Gear Root 5.
In above-mentioned technical proposal, the frequency for the sweeping laser that the frequency swept laser 1 exports is 40~60kHZ, preferably 50kHZ.Frequency is that the high speed frequency swept laser of 40~60kHZ ensure that the real-time of detection, high speed frequency swept laser scanning hair Out in certain wave band wavelength be in periodical linear change light.
It is as shown in Figure 1 overlength polarization-maintaining fiber grating schematic diagram.The grid cycle of overlength polarization-maintaining fiber grating is short, and grid region Length is long, and because there are birefringent phenomenons inside it, in actual analysis, overlength polarization-maintaining fiber grating can be waited Two overlength optical fiber gratings under identical environment are imitated into, and every overlength optical fiber grating can be equivalent at multiple short gratings Arrange, when it is secured at Gear Root, it is equivalent at two overlength optical fiber grating different locations respectively correspond It is different it is equivalent at short grating, these it is equivalent at the strain that senses of short grating be exactly suffered by its corresponding position tooth root it is curved What transverse stress generated, measurement full distributed in this way ensure that the high spatial resolution of detection system, can be made by the method The spatial resolution of system is less than 1mm.
It is illustrated in figure 2 the stickup schematic diagram of overlength polarization-maintaining fiber grating.Overlength polarization-maintaining fiber grating is pasted on along the facewidth At Gear Root, measured stress can be converted the bending stress of tooth root corresponding points.
A kind of full distributed Dedenda's bending stress dynamic testing method using above-mentioned apparatus, which is characterized in that it includes Following steps:
Step 1: tested gear is placed in stationary state；
Step 2: frequency swept laser 1 issues sweeping laser, which enters optical splitter C1；
Step 3: the first output end output amendment channel sweeping laser signal of optical splitter C1, the second of optical splitter C1 Output end exports Measurement channel sweeping laser signal；
Step 4: the amendment channel sweeping laser signal in step 3 enters optical splitter C2 and is divided into two beam sweeping lasers；Step Measurement channel sweeping laser signal enters coupler C3 after isolator 9 and is divided into two beam sweeping lasers in rapid 3；
Step 5: the sweeping laser of the first output end of optical splitter C2 output enters coupler C4, and the first of coupler C4 The sweeping laser of output end output is directly entered the input terminal of coupler C6, and the frequency sweep of the second output terminal output of coupler C4 swashs Light enters the input terminal of coupler C6, and the sweeping laser with the output of the first output end of coupler C4 after time delay optical fiber 7 Photo-beat phenomenon is generated in coupler C6, the beat signal of photodetector D1 acquisition coupler C6 output is simultaneously converted into corresponding Electric signal；
The sweeping laser of the second output terminal output of optical splitter C2 is filtered by wavelength calibration tool 8, photodetection The optical signal of 8 output of device D2 acquisition wavelength calibration tool is simultaneously converted into corresponding electric signal；
The sweeping laser of the first output end output of coupler C3 is directly entered polarization-maintaining photo-coupler C5；The of coupler C3 The sweeping laser of two output ends output enters the polarization-maintaining fiber grating 6 being affixed in Gear Root 5, and polarization-maintaining fiber grating 6 reflects The laser signal of two kinds of polarization states, the laser signal of above two polarization state enter polarization-maintaining photo-coupler C5, and the of coupler C3 The sweeping laser of one output end output and the laser signal of above two polarization state generate photo-beat in polarization-maintaining photo-coupler C5, protect The beat signal of polarisation coupler C5 output is distinguished by the beat frequency light that analyzer A1 and analyzer A2 isolate two kinds of polarization states Into photodetector D3 and photodetector D4, photodetector D1, photodetector D2, photodetector D3 and photoelectricity are visited After survey device D4 converts electric signal for the optical signal detected respectively, it is transferred to processor 2；
Step 6: the electric signal obtained in processor 2 with photodetector D1 is to photodetector D2, photodetector The electric signal that D3 and photodetector D4 are obtained carries out interpolation resampling, to compensate the nonlinear effect of frequency swept laser 1；Locating The electric signal obtained in reason device 2 with photodetector D2 is modified the sweep velocity of frequency swept laser 1；In processor 2 Staged demodulation processing is carried out to the obtained electric signal of photodetector D2 and photodetector D3 respectively, obtains polarization-maintaining fiber grating Respectively demodulation is segmented the wavelength under two kinds of polarization states on 6；Processor 2 decouples the wavelength under two kinds of obtained polarization states, Eliminate influence of the temperature to testing result, obtain under above two polarization state each staged demodulation section on polarization-maintaining fiber grating 6 just Beginning wavelength Xi, initial wavelength λiFor be tested gear stationary when polarization-maintaining fiber grating 6 on each staged demodulation section wavelength；
Step 7: in the rotation of tested gear, obtaining being tested gear under above two polarization state according to the step of step 2~6 When movement on polarization-maintaining fiber grating 6 each staged demodulation section wavelength, and find out under two kinds of polarization states be tested gear stationary and movement Each staged demodulation section wavelength difference Δ λ of state, staged demodulation section wavelength difference Δ λ are only strained influence；
Step 8: processor 2 calculates strain stress suffered by each staged demodulation section of polarization-maintaining fiber grating 6 according to the following formulai；
Δ λ=(1-P) λiεi
Wherein, P is effective strain optical coefficient of polarization-maintaining fiber grating 6, εiFor suffered by each staged demodulation section of polarization-maintaining fiber grating 6 Strain, when calculating, Δ λ and λiArbitrarily select the value under the same polarization state；
Then, by polarization-maintaining fiber grating 6 each staged demodulation section institute it is strained according to recklessly can law obtain it is corresponding in real time Tooth root distribution bending stresses.
In above-mentioned technical proposal, the length of the staged demodulation section is 1mm.
In the step 3 of above-mentioned technical proposal, the first output end of optical splitter C1 and the splitting ratio of second output terminal are 1: 99。
In the step 4 of above-mentioned technical proposal, amendment channel sweeping laser signal enters optical splitter C2 by the splitting ratio of 1:1 It is divided into two beam sweeping lasers.
The present invention can more precisely and real-time dynamicly detect at tooth root in overlength polarization-maintaining fiber grating it is equivalent at Two overlength optical fiber gratings be respectively in the central wavelength drift that strain front and back occurs, temperature-compensating can be achieved after decoupling, then tie Hooke's law in the stress sensing model and the mechanics of materials of light combination grid, the bending that can accurately obtain at tooth root each point are answered Force value, spatial resolution with higher, the high speed frequency swept laser used in demodulating system ensure that the real-time of detection, System structure is simple, does not interfere vulnerable to extraneous factors such as temperature, electromagnetism.
The content that this specification is not described in detail belongs to the prior art well known to professional and technical personnel in the field.

Claims (7)

1.一种利用全分布式齿根弯曲应力动态检测装置的全分布式齿根弯曲应力动态检测方法，全分布式齿根弯曲应力动态检测装置包括扫频激光器(1)、光分路器C1、光分路器C2、耦合器C3、耦合器C4、保偏光耦合器C5、耦合器C6、检偏器A1、检偏器A2、光电探测器D1、光电探测器D2、光电探测器D3、光电探测器D4、光环行器(3)、光纤旋转连接器(4)、延时光纤(7)、波长校准具(8)、隔离器(9)、处理器(2)、沿齿轮齿根(5)轴向贴在齿轮齿根(5)上的保偏光纤光栅(6)，其中，所述扫频激光器(1)的扫频信号输出端连接光分路器C1的输入端，光分路器C1的第一输出端连接光分路器C2的输入端，光分路器C1的第二输出端通过隔离器(9)连接耦合器C3的输入端，光分路器C2的第一输出端连接耦合器C4的输入端，光分路器C2的第二输出端连接波长校准具(8)的输入端，耦合器C4的第一输出端连接耦合器C6的输入端，耦合器C4的第二输出端通过延时光纤(7)连接耦合器C6的输入端，耦合器C6的输出端连接光电探测器D1的输入端，波长校准具(8)的输出端连接光电探测器D2的输入端，耦合器C3的第一输出端连接保偏光耦合器C5的输入端，耦合器C3的第二输出端连接光环行器(3)的第一接口，光环行器(3)的第二接口连接光纤旋转连接器(4)的固定端接线口，光纤旋转连接器(4)的旋转端接线口连接保偏光纤光栅(6)的一端，光环行器(3)的第三接口连接保偏光耦合器C5的输入端，保偏光耦合器C5的第一输出端通过检偏器A1连接光电探测器D3的输入端，保偏光耦合器C5的第二输出端通过检偏器A2连接光电探测器D4的输入端，光电探测器D1、光电探测器D2、光电探测器D3和光电探测器D4的信号输出端均连接处理器(2)的信号输入端；1. A fully distributed tooth root bending stress dynamic detection method utilizing a fully distributed tooth root bending stress dynamic detection device, the fully distributed tooth root bending stress dynamic detection device comprising a frequency sweep laser (1), an optical splitter C1 , optical splitter C2, coupler C3, coupler C4, polarization maintaining optical coupler C5, coupler C6, analyzer A1, analyzer A2, photodetector D1, photodetector D2, photodetector D3, Photodetector D4, optical circulator (3), optical fiber rotary connector (4), time delay optical fiber (7), wavelength calibration tool (8), isolator (9), processor (2), along the tooth root of the gear (5) A polarization-maintaining fiber grating (6) axially attached to the gear tooth root (5), wherein the frequency-sweeping signal output end of the frequency-sweeping laser (1) is connected to the input end of the optical splitter C1, and the optical The first output terminal of the splitter C1 is connected to the input terminal of the optical splitter C2, the second output terminal of the optical splitter C1 is connected to the input terminal of the coupler C3 through the isolator (9), and the second output terminal of the optical splitter C2 is connected to the input terminal of the coupler C3 through the isolator (9). An output end is connected to the input end of the coupler C4, the second output end of the optical splitter C2 is connected to the input end of the wavelength calibration tool (8), the first output end of the coupler C4 is connected to the input end of the coupler C6, and the coupler The second output end of C4 is connected to the input end of the coupler C6 through the delay fiber (7), the output end of the coupler C6 is connected to the input end of the photodetector D1, and the output end of the wavelength calibration tool (8) is connected to the photodetector D2 the input end of the coupler C3, the first output end of the coupler C3 is connected to the input end of the polarization maintaining optical coupler C5, the second output end of the coupler C3 is connected to the first interface of the optical circulator (3), and the second output end of the optical circulator (3) The second port is connected to the fixed end port of the optical fiber rotary connector (4), the rotary end port of the optical fiber rotary connector (4) is connected to one end of the polarization-maintaining fiber grating (6), and the third port of the optical circulator (3) is connected to The input terminal of the polarization-maintaining optical coupler C5, the first output terminal of the polarization-maintaining optical coupler C5 is connected to the input terminal of the photodetector D3 through the analyzer A1, and the second output terminal of the polarization-maintaining optical coupler C5 is connected to the photoelectric detector through the analyzer A2. The input end of the detector D4, the signal output ends of the photodetector D1, the photodetector D2, the photodetector D3 and the photodetector D4 are all connected to the signal input end of the processor (2); 其特征在于，全分布式齿根弯曲应力动态检测方法，包括如下方法：It is characterized in that the fully distributed dynamic detection method of tooth root bending stress includes the following methods: 步骤1：将被测齿轮置于静止状态；Step 1: Put the gear under test in a static state; 步骤2：扫频激光器(1)发出扫频激光，该扫频激光进入光分路器C1；Step 2: The frequency sweep laser (1) emits a frequency sweep laser, and the frequency sweep laser enters the optical splitter C1; 步骤3：光分路器C1的第一输出端输出修正通道扫频激光信号，光分路器C1的第二输出端输出测量通道扫频激光信号；Step 3: the first output end of the optical splitter C1 outputs the correction channel frequency sweep laser signal, and the second output end of the optical splitter C1 outputs the measurement channel frequency sweep laser signal; 步骤4：步骤3中的修正通道扫频激光信号进入光分路器C2分成两束扫频激光；步骤3中测量通道扫频激光信号经过隔离器(9)后进入耦合器C3被分成两束扫频激光；Step 4: The swept-frequency laser signal of the correction channel in step 3 enters the optical splitter C2 and is divided into two beams of swept-frequency laser; in step 3, the swept-frequency laser signal of the measurement channel passes through the isolator (9) and then enters the coupler C3 and is divided into two beams Sweep laser; 步骤5：光分路器C2的第一输出端输出的扫频激光进入耦合器C4，耦合器C4的第一输出端输出的扫频激光直接进入耦合器C6的输入端，耦合器C4的第二输出端输出的扫频激光经过延时光纤(7)后进入耦合器C6的输入端，并与耦合器C4的第一输出端输出的扫频激光在耦合器C6内产生光拍现象，光电探测器D1采集耦合器C6输出的拍频信号并转化为对应的电信号；Step 5: The swept-frequency laser output from the first output end of the optical splitter C2 enters the coupler C4, and the swept-frequency laser output from the first output end of the coupler C4 directly enters the input end of the coupler C6. The swept-frequency laser output from the second output end enters the input end of the coupler C6 after passing through the delay fiber (7), and generates a light beat phenomenon in the coupler C6 with the swept-frequency laser output from the first output end of the coupler C4. The detector D1 collects the beat frequency signal output by the coupler C6 and converts it into a corresponding electrical signal; 光分路器C2的第二输出端输出的扫频激光通过波长校准具(8)进行滤波，光电探测器D2采集波长校准具(8)输出的光信号并转化为对应的电信号；The frequency sweep laser output from the second output end of the optical splitter C2 is filtered by the wavelength calibration tool (8), and the photodetector D2 collects the optical signal output by the wavelength calibration tool (8) and converts it into a corresponding electrical signal; 耦合器C3的第一输出端输出的扫频激光直接进入保偏光耦合器C5；耦合器C3的第二输出端输出的扫频激光进入贴于齿轮齿根(5)上的保偏光纤光栅(6)，保偏光纤光栅(6)反射出两种偏振态的激光信号，上述两种偏振态的激光信号进入保偏光耦合器C5，耦合器C3的第一输出端输出的扫频激光和上述两种偏振态的激光信号在保偏光耦合器C5内产生光拍，保偏光耦合器C5输出的拍频信号通过检偏器A1和检偏器A2分离出两种偏振态的拍频光分别进入光电探测器D3和光电探测器D4，光电探测器D1、光电探测器D2、光电探测器D3和光电探测器D4分别将探测到的光信号转化为电信号后，传输给处理器(2)；The swept-frequency laser output from the first output end of the coupler C3 directly enters the polarization-maintaining optical coupler C5; the swept-frequency laser output from the second output end of the coupler C3 enters the polarization-maintaining fiber grating ( 6), the polarization-maintaining fiber grating (6) reflects laser signals of two polarization states, and the laser signals of the above-mentioned two polarization states enter the polarization-maintaining optical coupler C5, and the swept-frequency laser output from the first output end of the coupler C3 and the above-mentioned The laser signals of the two polarization states generate light beats in the polarization-maintaining optical coupler C5, and the beat-frequency signal output by the polarization-maintaining optical coupler C5 is separated by the analyzer A1 and the analyzer A2 to separate the beat-frequency light of the two polarization states and enter respectively. The photodetector D3 and the photodetector D4, the photodetector D1, the photodetector D2, the photodetector D3 and the photodetector D4 respectively convert the detected optical signals into electrical signals, and then transmit them to the processor (2); 步骤6：在处理器(2)中用光电探测器D1得到的电信号对光电探测器D2、光电探测器D3和光电探测器D4得到的电信号进行插值重采样，来补偿扫频激光器(1)的非线性效应；在处理器(2)中用光电探测器D2得到的电信号对扫频激光器(1)的扫频速度进行修正；在处理器(2)中对光电探测器D2和光电探测器D3得到的电信号分别进行分段解调处理，得到保偏光纤光栅(6)上各解调分段在两种偏振态下的波长；处理器(2)对得到的两种偏振态下的波长进行解耦，消除温度对检测结果的影响，得到上述两种偏振态下保偏光纤光栅(6)上各分段解调段的初始波长λi，初始波长λi为被测齿轮静止时保偏光纤光栅(6)上各分段解调段的波长；Step 6: In the processor (2), the electrical signals obtained by the photodetector D1 are used to interpolate and resample the electrical signals obtained by the photodetector D2, the photodetector D3 and the photodetector D4 to compensate the frequency sweep laser (1). ) nonlinear effect; in the processor (2), use the electrical signal obtained by the photodetector D2 to correct the sweeping speed of the frequency swept laser (1); in the processor (2), the photodetector D2 and the photoelectric The electrical signals obtained by the detector D3 are respectively subjected to segmental demodulation processing to obtain wavelengths of each demodulated segment on the polarization-maintaining fiber grating (6) under two polarization states; the processor (2) analyzes the obtained two polarization states. Decoupling the wavelength under the two polarization states to eliminate the influence of temperature on the detection results, and obtain the initial wavelength λ i of each segmented demodulation segment on the polarization-maintaining fiber grating (6) under the above two polarization states, and the initial wavelength λ i is the measured gear. The wavelength of each segmented demodulation segment on the polarization-maintaining fiber grating (6) at rest; 步骤7：在被测齿轮转动时，依据步骤2～6的方式得到上述两种偏振态下被测齿轮运动时保偏光纤光栅(6)上各分段解调段的波长，并求出两种偏振态下被测齿轮静止与运动状态的各分段解调段波长差Δλ，该分段解调段波长差Δλ只受到应变影响；Step 7: When the measured gear rotates, obtain the wavelengths of each segmented demodulation segment on the polarization-maintaining fiber grating (6) when the measured gear moves in the above two polarization states according to the methods of steps 2 to 6, and obtain the two wavelengths. The wavelength difference Δλ of each segmented demodulation segment between the static and moving states of the tested gear in each polarization state, and the wavelength difference Δλ of the segmented demodulation segment is only affected by strain; 步骤8：处理器(2)根据如下公式计算保偏光纤光栅(6)各分段解调段所受应变εi；Step 8: the processor (2) calculates the strain ε i of each segmented demodulation section of the polarization-maintaining fiber grating (6) according to the following formula; Δλ＝(1-P)λiεi Δλ=(1-P)λ i ε i 其中，P是保偏光纤光栅(6)的有效光弹系数，εi为保偏光纤光栅(6)各分段解调段所受应变，计算时，Δλ和λi任意选择同一个偏振态下的值即可；Among them, P is the effective photoelastic coefficient of the polarization-maintaining fiber grating (6), ε i is the strain of each segmented demodulation segment of the polarization-maintaining fiber grating (6), and the same polarization state is arbitrarily selected for Δλ and λ i during calculation The value below can be; 然后，通过保偏光纤光栅(6)各分段解调段所受应变依据胡可定律得到对应的实时齿根分布式弯曲应力值。Then, the corresponding real-time distributed bending stress value of the tooth root is obtained according to Hu Ke's law through the strain of each segmented demodulation section of the polarization-maintaining fiber grating (6). 2.根据权利要求1所述的全分布式齿根弯曲应力动态检测方法，其特征在于：所述光分路器C1的第一输出端与第二输出端的分束比为1:99，光分路器C2的第一输出端与第二输出端的分束比为1:1。2 . The fully distributed tooth root bending stress dynamic detection method according to claim 1 , wherein the splitting ratio between the first output end and the second output end of the optical splitter C1 is 1:99, and the optical The splitting ratio of the first output end and the second output end of the splitter C2 is 1:1. 3.根据权利要求1所述的全分布式齿根弯曲应力动态检测方法，其特征在于：所述保偏光纤光栅(6)的长度等于齿轮齿根(5)的轴向长度。3 . The fully distributed tooth root bending stress dynamic detection method according to claim 1 , wherein the length of the polarization-maintaining fiber grating ( 6 ) is equal to the axial length of the gear tooth root ( 5 ). 4 . 4.根据权利要求1所述的全分布式齿根弯曲应力动态检测方法，其特征在于：所述扫频激光器(1)输出的扫频激光的频率为40～60kHZ。4 . The fully distributed tooth root bending stress dynamic detection method according to claim 1 , wherein the frequency of the frequency sweep laser output by the frequency sweep laser ( 1 ) is 40-60 kHz. 5 . 5.根据权利要求1所述的全分布式齿根弯曲应力动态检测方法，其特征在于：所述分段解调段的长度为1mm。5 . The fully distributed tooth root bending stress dynamic detection method according to claim 1 , wherein the length of the segmented demodulation section is 1 mm. 6 . 6.根据权利要求1所述的全分布式齿根弯曲应力动态检测方法，其特征在于：所述步骤3中，光分路器C1的第一输出端与第二输出端的分束比为1:99。6 . The fully distributed tooth root bending stress dynamic detection method according to claim 1 , wherein in the step 3, the splitting ratio between the first output end and the second output end of the optical splitter C1 is 1. 7 . :99. 7.根据权利要求1所述的全分布式齿根弯曲应力动态检测方法，其特征在于：所述步骤4：步骤3中的修正通道扫频激光信号进入光分路器C2按1:1的分束比分成两束扫频激光。7. The fully distributed tooth root bending stress dynamic detection method according to claim 1, characterized in that: said step 4: the correction channel sweep laser signal in step 3 enters the optical splitter C2 at a ratio of 1:1. The split ratio is divided into two swept laser beams.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101526376A (en) * 2008-03-04 2009-09-09 电子科技大学 Polarization fiber sensor
CN102262177A (en) * 2011-07-05 2011-11-30 中国工程物理研究院流体物理研究所 Full-optical fiber pulse current sensor
CN102322880A (en) * 2011-08-18 2012-01-18 天津大学 Polarization sensitive distributive optical frequency domain reflection disturbance sensor and demodulation method
CN104101380A (en) * 2014-07-02 2014-10-15 西安交通大学 Method for measuring stress and strain of gear root of fixed center gear of planetary gear train
CN105588661A (en) * 2015-11-12 2016-05-18 哈尔滨工程大学 Device for simultaneous measurement of single-point and regional temperatures through preserving polarization fiber grating
CN106248118A (en) * 2016-07-15 2016-12-21 武汉理工大学 High wavelength resolution optical fiber grating regulating system and method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6731423B1 (en) * 2001-08-15 2004-05-04 Neumann Information Systems Inc Optical amplifier and method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101526376A (en) * 2008-03-04 2009-09-09 电子科技大学 Polarization fiber sensor
CN102262177A (en) * 2011-07-05 2011-11-30 中国工程物理研究院流体物理研究所 Full-optical fiber pulse current sensor
CN102322880A (en) * 2011-08-18 2012-01-18 天津大学 Polarization sensitive distributive optical frequency domain reflection disturbance sensor and demodulation method
CN104101380A (en) * 2014-07-02 2014-10-15 西安交通大学 Method for measuring stress and strain of gear root of fixed center gear of planetary gear train
CN105588661A (en) * 2015-11-12 2016-05-18 哈尔滨工程大学 Device for simultaneous measurement of single-point and regional temperatures through preserving polarization fiber grating
CN106248118A (en) * 2016-07-15 2016-12-21 武汉理工大学 High wavelength resolution optical fiber grating regulating system and method

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