CN113984385A - Armored vehicle gear box fault diagnosis method research based on optical fiber ring acoustic emission sensor - Google Patents
Armored vehicle gear box fault diagnosis method research based on optical fiber ring acoustic emission sensor Download PDFInfo
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- CN113984385A CN113984385A CN202111239422.0A CN202111239422A CN113984385A CN 113984385 A CN113984385 A CN 113984385A CN 202111239422 A CN202111239422 A CN 202111239422A CN 113984385 A CN113984385 A CN 113984385A
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- 229920001707 polybutylene terephthalate Polymers 0.000 claims description 7
- 230000007547 defect Effects 0.000 claims description 6
- 238000001514 detection method Methods 0.000 claims description 6
- -1 polybutylene terephthalate Polymers 0.000 claims description 6
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- 239000004519 grease Substances 0.000 claims description 4
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical group [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 3
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- 229910052744 lithium Inorganic materials 0.000 claims description 3
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
- G01M13/028—Acoustic or vibration analysis
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
- G01M13/021—Gearings
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
The invention provides a fault diagnosis method for a gearbox of an armored car based on an optical fiber ring acoustic emission sensor, which comprises a measurement part and a demodulation part; the measuring part mainly detects acoustic emission signals through the optical fiber ring sensor and comprises the arrangement, fixation and connection of the optical fiber ring acoustic emission sensor; the demodulation part consists of a photoelectric conversion module, an amplification module, a filtering module, an acquisition module, a resonance demodulation and other signal processing modules. The invention is mainly used for fault diagnosis of the gearbox of the armored vehicle, and has the advantages of electromagnetic interference resistance, good stability, adaptability to the working environment of the gearbox filled with oil stains, and the like.
Description
Technical Field
The invention is used in the field of acoustic emission detection, and particularly relates to an optical fiber ring acoustic emission sensor which is suitable for the fields of strong electromagnetic interference and acoustic emission in a high-temperature environment.
Background
With the improvement of the economic and scientific levels of China, the national defense military strength of China is continuously developed and advanced, and armored vehicles serve as representatives of the land military strength in modern war and play an irreplaceable role in battlefields. The gear box is used as an important part for power transmission in the running process of the armored vehicle, and the health condition of the gear box is particularly important for the normal running of the armored vehicle.
In recent years, the optical fiber sensing technology is rapidly developed, and the optical fiber can be used in some severe environments due to the advantages of corrosion resistance, low cost, small volume, light weight, electromagnetic interference resistance and the like. Therefore, the acoustic emission signal is measured by using the optical fiber ring acoustic emission sensor, namely winding the single-mode optical fiber on the cylindrical framework made of the PE material and packaging the sensor.
In the aspect of fault diagnosis of the gear box, signals received by the sensor are easily interfered by electric field and magnetic field factors in a high-speed operation state, so that safe and reliable high signal-to-noise ratio data are difficult to acquire by a traditional electric sensor, such as a piezoelectric ceramic sensor, when the operation state of the gear box is detected, and the optical fiber ring acoustic emission sensor is resistant to electromagnetic interference, so that the anti-interference performance is obviously better than that of the traditional electric sensor when the fault diagnosis of the gear box is performed, the corrosion resistance of the traditional electric sensor is stronger, and the traditional electric sensor can still normally work when the gear box is full of oil stains.
Disclosure of Invention
The invention aims to overcome the technical limitation of the prior art, introduce an optical fiber ring acoustic emission sensor into the field of fault detection of a gearbox of an armored vehicle, and provide a gearbox fault acoustic emission detection method based on optical fiber sensing.
The technical scheme adopted by the invention is as follows: a fault diagnosis method for a gearbox of an armored vehicle based on an optical fiber ring acoustic emission sensor comprises the steps of firstly finding a proper sensor sticking position on the surface of the gearbox, then arranging the sensors, and fixing the optical fiber ring sensor on the surface of the gearbox. And then, connecting jumper wires with the same length with a measuring ring and a reference ring of the optical fiber ring sensor, respectively connecting the measuring ring and the reference ring with a measuring light path and a reference light path of a demodulation case, outputting an electric signal by the demodulation case after photoelectric conversion, connecting an output end of the demodulation case with a preamplifier, amplifying the electric signal after the photoelectric conversion, acquiring the amplified signal by an industrial personal computer, and filtering, denoising and resonance demodulating the acoustic emission signal converted into the electric signal.
The fiber ring sensor measuring ring is arranged on the side surface and the top surface of the gear box and is used for sensing the maximum vibration of the gear box with different defects, but vibration signals acquired by a single sensor are not complete, so that a plurality of sensors are respectively fixed on the side surface and the top surface of the gear box.
The method sets different fixing modes aiming at the sensors at different positions, so that the sensors can normally work in the environment of high temperature and full of oil stains.
When the method is used for signal processing, firstly, digital filtering is carried out on a signal wire, then, the time domain characteristic and the frequency domain characteristic of the signal are combined, the signal is screened, and sensors at different positions intercept data with the same length for subsequent analysis.
The method performs resonance demodulation on the screened signals to obtain the low-frequency meshing frequency and fault frequency information of the gearbox, and selects band-pass filters with different frequency bands according to the frequency domain characteristics of the signals during resonance demodulation, but the band-pass filters have the same bandwidth.
Compared with the prior art, the invention has the advantages that:
(1) the invention applies the optical fiber ring acoustic emission sensor to the fault detection of the gear box, has the advantages of low cost, electromagnetic interference resistance, good sensitivity and reliability, long-term stable normal work and the like, and can adapt to the electromagnetic interference environment compared with the traditional electric sensor when detecting the defects of the gear box.
(2) The invention selects different fixing modes aiming at the optical fiber ring sensors at different positions of the gear box, so that the vibration signals can be stably measured at high temperature under the condition of being full of oil stains.
(3) The invention applies the resonance demodulation technology to the optical fiber ring acoustic emission detection technology, and can demodulate the meshing frequency and the fault frequency of the gearbox well.
Drawings
FIG. 1 is a schematic structural diagram of a fault diagnosis system of a gearbox of an armored vehicle based on an optical fiber ring acoustic emission sensor;
FIG. 2 is a schematic diagram of the arrangement of acoustic emission sensors of the fiber optic ring
FIG. 3 is a flow chart of vibration signal processing
Detailed Description
The invention is further described with reference to the following figures and detailed description.
As shown in fig. 1, a measurement ring 1 and a reference ring 2 of the optical fiber ring sensor are connected with a demodulation chassis 3 by jumper wires with a length of 10m, wherein the measurement ring 1 is arranged on the surface of a gearbox and is responsible for receiving vibration signals of the gearbox, and the reference ring 2 is in an environment without receiving acoustic emission signals; the demodulation cabinet 3 comprises a coupler, a light source and a photoelectric detector, and measurement light and reference light are provided; the optical fiber ring acoustic emission sensor loads the information of the acoustic emission signal on the optical signal, and the optical signal is converted into an electrical signal through the photoelectric conversion module of the demodulation case 3; the preamplifier 4 amplifies the amplitude of the electric signal, so that the electric signal can be conveniently collected by the industrial personal computer 5; the industrial personal computer 5 is mainly responsible for collecting the electric signals amplified by the preamplifier 4, processing the signals and demodulating fault signals of the gearbox.
As shown in fig. 2, 1 is a measuring ring of the optical fiber ring acoustic emission sensor adhered to the top surface of the gear box, 2 is a measuring ring of the optical fiber ring acoustic emission sensor adhered to the side surface of the gear box, 3 is a PBT elastic bandage, 4 is a cloth-based adhesive tape, 5 is a gear box oil supplementing channel, 6 is a transmission shaft connected with a motor, 7 is a gear box shell, and a plurality of protruding bolts are arranged on the shell and have great influence on the arrangement of the sensors together with the oil supplementing channel 5 and the gear box transmission shaft 6. When carrying out the sensor and arranging, because gear box shell 6 is comparatively smooth, and the surface is full of the oil stain, so can not directly carry out arranging of sensor, need clean its surface with the alcohol cotton earlier, look for the position that is fit for arranging optic fibre ring acoustic emission sensor, then to the position of pasting of difference, select different modes of pasting: the optical fiber ring sensor 1 arranged on the top surface of the gear box can be fixed by using a PBT (polybutylene terephthalate) elastic bandage 3, has good electrical insulation, has high thermal deformation temperature and can work for a long time at 140 ℃; the sensor 2 arranged on the side face of the gear box is characterized in that a cloth-based adhesive tape 4 which is made of polyethylene and gauze fibers through thermal compounding is selected, grease resistance and temperature resistance are achieved, and the sensor 2 can be well fixed on the side face of the gear box. The couplant is lithium-based grease prepared by mixing mineral oil and a thickening agent, is strong in oxidation resistance and adhesion, can be filled in gaps between the sensor and the surface of the gear box to enable the sensor and the gear box to be tightly attached, is uniformly coated on the bottom of the sensor, and is placed at a preset position. The optical fiber ring sensors 1 and 2 are small in size and light in weight, and can be stably attached to the surface of the gear box when the gear box runs at a high speed.
When a vibration signal 1 collected by an industrial personal computer is processed, firstly, the signal passes through a band-pass filter 2, the measuring range of an optical fiber ring sensor is combined, the frequency band range of the band-pass filter is selected to be 20K to 300KHz, low-frequency noise is filtered from the collected signal, then a stable signal time period is selected according to a time domain signal wave band, and as the rotating speed of a sun wheel of a gearbox is more than 6rps, and the sampling rate of a collecting card is 500K/s, a data length 3 of 5s is selected, so that the defect signal of the gearbox can be completely detected. And performing resonance demodulation 9 on the intercepted signal, selecting a frequency bandwidth of 10K according to resonance characteristics of a gear box component and a sensor, performing band-pass filtering 4, determining an upper limit cut-off frequency and a lower limit cut-off frequency of the band-pass filter according to the energy of the screened signal, covering a region with the maximum energy by the band-pass frequency band, performing envelope demodulation 5 by a Hilbert envelope method, passing the demodulated signal through a low-pass filter 6, and performing FFT7 processing to obtain a defect characteristic signal 8 of the gear box.
Although illustrative embodiments of the present invention have been described above to facilitate the understanding of the present invention by those skilled in the art, it should be understood that the present invention is not limited to the scope of the embodiments, and various changes may be made apparent to those skilled in the art as long as they are within the spirit and scope of the present invention as defined and defined by the appended claims, and all matters of the invention which utilize the inventive concepts are protected.
Claims (5)
1. In the method for diagnosing the faults of the gearbox of the armored vehicle based on the optical fiber ring acoustic emission sensor, in a figure 2, the acoustic emission sensor is applied to fault detection of the gearbox of the armored vehicle, and the optical fiber ring acoustic emission sensors (1) and (2) are pasted at different positions according to different measuring points. When carrying out the sensor and arranging, clean gear box shell (6) earlier with the alcohol cotton, look for the position that is fit for arranging optic fibre ring acoustic emission sensor, then to the position of pasting of difference, select different modes of pasting: the optical fiber ring sensor (1) is arranged on the top surface of the gear box and is fixed by using a PBT (polybutylene terephthalate) elastic bandage (3); the sensor (2) arranged on the side face of the gear box is fixed on the side face of the gear box by selecting a cloth-based adhesive tape (4) which takes thermal compounding of polyethylene and gauze fibers as a base material. The couplant is lithium-based grease prepared by mixing mineral oil and a thickening agent, is strong in oxidation resistance and adhesion, can be filled in gaps between the sensor and the surface of the gear box to enable the sensor and the gear box to be tightly attached, is uniformly coated on the bottom of the sensor, and is placed at a preset position.
2. A processing method based on vibration signals of an optical fiber ring acoustic emission sensor is disclosed, and a flow chart is shown in figure 3, and is characterized in that: the method comprises the following steps:
enabling a vibration signal (1) acquired by an industrial personal computer to pass through a band-pass filter (2) with a frequency band range of 20K to 300KHz, and filtering low-frequency noise in the signal; the method comprises the steps of selecting a data length (3) of 5s according to signal time domain characteristics to detect a gear box defect signal, then performing resonance demodulation (9), selecting a frequency bandwidth of 10K according to resonance characteristics of gear box components and a sensor to perform band-pass filtering (4), determining an upper limit cutoff frequency and a lower limit cutoff frequency of the band-pass filter according to energy of a screening signal, covering a region with maximum energy by the band-pass frequency, then performing envelope demodulation (5) by a Hilbert envelope method, passing the demodulated signal through a low-pass filter (6), and then performing FFT (7) processing, so that a defect characteristic signal (8) of the gear box can be obtained.
3. The method of claim 1, wherein: the optical fiber ring sensor (1) is arranged on the top surface of the gear box and is fixed by using a PBT (polybutylene terephthalate) elastic bandage (3); the sensor (2) arranged on the side face of the gear box is fixed on the side face of the gear box by selecting a cloth-based adhesive tape (4) which takes thermal compounding of polyethylene and gauze fibers as a base material.
4. The method of claim 1, wherein: the coupling agent is lithium-based grease prepared by blending mineral oil and a thickening agent.
5. The method for processing the vibration signal of the acoustic emission sensor with the optical fiber ring according to claim 2, wherein: the frequency band of a band-pass filter (2) through which the vibration signal (1) passes is in the range of 20K to 300KHz, and data having a data length (3) of 5s is selected, and then resonance demodulation (9) is performed.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111239422.0A CN113984385A (en) | 2021-10-25 | 2021-10-25 | Armored vehicle gear box fault diagnosis method research based on optical fiber ring acoustic emission sensor |
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| CN202111239422.0A CN113984385A (en) | 2021-10-25 | 2021-10-25 | Armored vehicle gear box fault diagnosis method research based on optical fiber ring acoustic emission sensor |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103344432A (en) * | 2013-06-04 | 2013-10-09 | 中国人民解放军陆军航空兵学院 | Method for detecting fiber bragg grating acoustic emission of helicopter bearing fault |
| EP2913638A1 (en) * | 2014-02-28 | 2015-09-02 | Fuji Jukogyo Kabushiki Kaisha | Vibration detection apparatus and vibration detection method |
| WO2015199839A1 (en) * | 2014-06-26 | 2015-12-30 | Baker Hughes Incorporated | Ofdr system for localized vibration detection |
| CN106338549A (en) * | 2016-09-05 | 2017-01-18 | 北京航空航天大学 | Multichannel optical fibre ring sound emission detection system and demodulation method |
| WO2017015960A1 (en) * | 2015-07-30 | 2017-02-02 | 北京一纤百城光电科技有限公司 | Acoustic-emission-based health monitoring method and system |
-
2021
- 2021-10-25 CN CN202111239422.0A patent/CN113984385A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103344432A (en) * | 2013-06-04 | 2013-10-09 | 中国人民解放军陆军航空兵学院 | Method for detecting fiber bragg grating acoustic emission of helicopter bearing fault |
| EP2913638A1 (en) * | 2014-02-28 | 2015-09-02 | Fuji Jukogyo Kabushiki Kaisha | Vibration detection apparatus and vibration detection method |
| WO2015199839A1 (en) * | 2014-06-26 | 2015-12-30 | Baker Hughes Incorporated | Ofdr system for localized vibration detection |
| WO2017015960A1 (en) * | 2015-07-30 | 2017-02-02 | 北京一纤百城光电科技有限公司 | Acoustic-emission-based health monitoring method and system |
| CN106338549A (en) * | 2016-09-05 | 2017-01-18 | 北京航空航天大学 | Multichannel optical fibre ring sound emission detection system and demodulation method |
Non-Patent Citations (5)
| Title |
|---|
| YU GUO,ET AL: "Localized faults detection of planetary gear sets based on resonance demodulation and vibration separation", 2018 IEEE INTERNATIONAL INSTRUMENTATION AND MEASUREMENT TECHNOLOGY CONFERENCE(I2MTC) * |
| YU GUO,ET AL: "Tooth Root Crack Detection of Planet and Sun Gears Based on Resonance Demodulation and Vibration Separation", IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, vol. 69, no. 1, pages 65 - 75, XP011760211, DOI: 10.1109/TIM.2019.2893011 * |
| 李宁;魏鹏;莫宏;梅盛开;黎敏;: "光纤光栅声发射检测新技术用于轴承状态监测的研究", 振动与冲击, no. 03, pages 180 - 185 * |
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