CN110940522A - Bearing fault periodic pulse sparse separation and diagnosis method under strong background noise - Google Patents
Bearing fault periodic pulse sparse separation and diagnosis method under strong background noise Download PDFInfo
- Publication number
- CN110940522A CN110940522A CN201910279626.3A CN201910279626A CN110940522A CN 110940522 A CN110940522 A CN 110940522A CN 201910279626 A CN201910279626 A CN 201910279626A CN 110940522 A CN110940522 A CN 110940522A
- Authority
- CN
- China
- Prior art keywords
- fault
- periodic
- bearing
- vibration acceleration
- vertical direction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Classifications
-
- 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
- G01M13/04—Bearings
- G01M13/045—Acoustic or vibration analysis
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- General Physics & Mathematics (AREA)
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
The invention relates to a bearing fault periodic pulse sparse separation and diagnosis method under strong background noise, which is characterized by comprising the following steps of: respectively installing acceleration sensors in the horizontal direction and the vertical direction of a bearing seat to be detected, and acquiring a vibration acceleration signal in the horizontal direction and a vibration acceleration signal in the vertical direction of the bearing; and establishing a target cost function, and respectively calculating the horizontal direction periodic fault pulse signals and the vertical direction periodic fault pulse signals of the horizontal direction vibration acceleration signals and the vertical direction vibration acceleration signals through iteration of an alternating direction multiplier method. The invention can successfully extract the period information of the hidden unknown periodic pulse in the noisy signal without any priori knowledge, and has high pulse separation accuracy and strong stability. The invention can greatly reduce the interference of background working conditions and system structure noise, and the extracted fault periodic transient pulse sequence is clear and has no aliasing.
Description
Technical Field
The invention relates to a mechanical fault diagnosis and signal processing method, in particular to a bearing fault periodic pulse sparse separation and diagnosis method under strong background noise.
Background
The bearing is used as a key part of rotary mechanical equipment and widely applied to the fields of various commercial and industrial engineering, such as wind power generation, automobile gearboxes, high-speed rails, ships, aerospace engines and the like. The health state monitoring of the bearing during the operation of the equipment is related to the performance, safety and service life of the whole system, the degradation state of the bearing in service is accurately and timely monitored, and the method has extremely important research significance on the reliable operation of the system, the production of enterprises and the life safety of operators.
Generally, when a bearing element has local faults, such as inner ring pitting, outer ring peeling, ball abrasion and the like, a series of periodic fault pulse impact signals are excited along with the operation of a system, and the periodic fault pulse signals are key information for monitoring the health state of the bearing. However, in practical engineering, due to the interference of external noise, the influence of system structure, and the like, useful fault pulse signals are often submerged in the external noise, and therefore, it is a difficult point in the field of mechanical fault diagnosis in recent years to effectively separate periodic fault pulse signals from actual observation signals.
Disclosure of Invention
The purpose of the invention is: the periodic fault pulse signal is effectively isolated from the actual observed signal.
In order to achieve the purpose, the technical scheme of the invention is to provide a bearing fault periodic pulse sparse separation and diagnosis method under strong background noise, which is characterized by comprising the following steps of:
in the formula (I), the compound is shown in the specification,representing a wavelet transform coefficient to be estimated; ω represents a wavelet transform coefficient; f (ω) represents the objective cost function; y represents the vibration acceleration signal in the horizontal direction or the vertical direction obtained in step 1A vibration acceleration signal; lambda [ alpha ]jRepresenting the regularization parameter at the time scale j; continuous wavelet transform of transform coefficients x: omegaj,k=Wj,kx, in the formula, Wj,kThe wavelet transform is performed on a translation scale j and a time scale k, y is Ax + w, A represents a matrix with Toeplitz, and w represents background noise or interference components; a isjRepresenting a penalty function scale coefficient; phi (omega)j,k;aj) β denotes regularization parameters, D denotes a first order differential matrix;
Preferably, after the step 3, the method further comprises:
and carrying out envelope demodulation on the horizontal direction periodic fault pulse signal and the vertical direction periodic fault pulse signal by using a Hilbert envelope demodulation method, extracting bearing fault characteristic frequency and frequency multiplication thereof, comparing the extracted bearing fault characteristic frequency with theoretical fault characteristic frequency, and identifying the fault position of the bearing.
The method provided by the invention can effectively filter the interference component and the serious background noise, and simultaneously separates the periodic fault pulse signal hidden in the noise.
Compared with the prior art, the invention has the following advantages:
compared with the traditional signal filtering method, the method has the advantages that any priori knowledge is not needed to be known in advance, the period information of the hidden unknown periodic pulses in the noisy signals can be successfully extracted, and the pulse separation accuracy is high and the stability is high.
Secondly, the regularization target cost function is constructed by utilizing a non-convex penalty Daubechies wavelet function and a total variation algorithm, and the target cost function has strict convexity.
The method can greatly reduce the interference of background working conditions and system structure noise, the extracted fault periodic instantaneous pulse sequence is clear and has no aliasing, the amplitude of the fault characteristic frequency obtained by demodulation is high, the fault harmonic component is obvious, the method is suitable for real-time fault routing inspection of other rotating mechanical equipment such as a bearing or a gear box and the like, and sudden faults are avoided, and an important theoretical basis can be provided for the health management of enterprise equipment.
Drawings
FIG. 1 is a flow chart of a method of the present invention;
fig. 2 is a schematic view of an experimental platform according to an embodiment of the present invention, in which 1 denotes a non-driving end of an input shaft, 2 denotes a faulty bearing, 3 denotes a non-driving end of an output shaft, 4 denotes a driving end of the input shaft, and 5 denotes a driving end of the output shaft;
FIG. 3(a) is a time domain waveform of an original vibration acceleration signal acquired in a horizontal direction;
fig. 3(b) is an envelope spectrum of an original vibration acceleration signal acquired in a vertical direction;
FIG. 3(c) is a time domain waveform of the original vibration acceleration signal in the horizontal direction;
FIG. 3(d) is an envelope spectrum of the original vibration acceleration signal in the vertical direction;
FIG. 4(a) is a horizontal direction fault periodic pulse obtained using the method of the present invention;
FIG. 4(b) is an envelope spectrum of a horizontal fault periodic pulse signal;
FIG. 4(c) is a vertical direction fault periodic pulse obtained using the method of the present invention;
fig. 4(d) is an envelope spectrum of a vertical direction fault periodic pulse signal.
Detailed Description
The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.
The invention provides a bearing fault periodic pulse sparse separation and diagnosis method under strong background noise, which comprises the following steps:
1) typically, the vibration sensor collects a device fault observation signalCan be expressed as y ═ x0+ w is Ax + w, wherein,for the purpose of background noise or interference components,in order to be a periodic fault pulse signal,for transforming coefficients, matricesWith Toeplitz matrix. The conventional method of minimizing the L1 norm utilizes a linear least squares model to estimate the periodic fault pulse signal, i.e.In the formula (I), the compound is shown in the specification,representing a periodic fault pulse signal, f (x) is a target cost function,is a secondary data fidelity item, whereinIs a penalty function (i.e., L1-norm), λ0And λ1A regularization parameter is represented as a function of,is a first order differential matrix, i.e.The matrix D determines the sparsity of the fault pulse signal. The traditional minimization L1-norm method can be solved through a full-variational model and a soft threshold algorithm, namelyWherein Soft (·,) is a Soft threshold function ofTvd (·,. cndot.) is a fully-variational model with the expressionWhere Prox (-) is the neighbor of the then-current signal y.
2) Given a signal x, its continuous wavelet transformWhere i and j are the mother wavelet translation factor and time factor, respectively. The continuous wavelet transform of the signal x can be simplified to ωi,j=Wi,jx, wherein Wi,jFor wavelet transformation at a translation scale i and a time scale j, omegai,jRepresenting translationWavelet transform coefficients at scale i and time scale j. According to the shift invariant property and Parseval theorem WTThe wavelet transform coefficient W can be modeled byAnd calculating to obtain the final product of the formula,representing wavelet transform coefficients, λ, to be estimatedjAnd β are regularization parameters, ajRepresenting the penalty function scaling factor. Under the translation scale i and the time scale j, the two norms of the wavelet transform coefficient omega satisfyFinal periodic fault pulse signalCan be calculated by inverse wavelet transform, i.e.
3) Established objective cost functionIn the model, where phi (x; a) is phi (omega)jK, k; a) and a is not less than 0 and meets the following 7 conditions:
(I) penalty functions phi (x; a) inContinuously; (II) the penalty function phi (x; a) is inUpper and lower order conductibility; (III) the penalty function phi (x; a) is a symmetric function, i.e., phi (-x; a) is phi (x; a); (IV) φ' (x; a) > 0,(V)φ″(x;a)≤0,(VI)φ′(0+;a)=1;(VII)
assuming that the non-convex penalty function φ (x; a) satisfies the above-mentioned 7 conditions, for each scale j, a ≦ a is satisfied if 0j<1/λjThen, a target cost function is proposedHas strict convexity.
the proposed objective cost function may be further expressed asDue to the last item L1-norm β | | | DWTω||1Is a convex function, so to prove that the objective cost function has strict convexity, it is only necessary to prove that the first term in the formula F (ω) is a convex function. Optimizing the model according to linear least squaresWhich can be expressed asWhere phi (x; a) is a penalty function. The function θ (y, λ, a) has a strict convexity if and only if φ' (0)+)≥φ′(0-) That is, 1+ λ φ "(x) > 0, for allx ≠ 0 is obtainedFor standard penalty functions, e.g. arctangent penalty functionAnd logarithmic penalty functionDue to the fact thatIts second derivative satisfiesThen there isFurther, due toThe term can be expressed as θ ([ W ]y]j,k;λj,aj) When it is satisfiedθ([Wy]j,k;λj,aj) Is a convex function. Therefore when the coefficient a isjSatisfy the requirement ofProposed objective cost functionHas strict convexity.
5) The proposed objective cost function, the solving algorithm of which can be obtained by iterative calculation through an alternative direction multiplier method, specifically:
for any j, assume parameter ajSatisfy the requirement ofFor evaluating periodic fault pulse signalsProposed objective cost functionCan be decomposed intoWhereing2(u)=β||DWTu||1To decomposition formula g1(omega) and g2(u) introducing a Lagrangian multiplier mu > 0 to obtainAccording to the principle of the alternative direction multiplier method, the decomposition formula can be: d ═ d- (u- ω). When it is satisfied withIt can be seen thatAndall have strict convexity.
For arbitrary j and k, equationCan be converted into a solution modelWherein p ═ y [ Wy + mu (u-d)]/(. mu. + 1). Therefore, using a soft threshold function and a full variational algorithm, equationIs solved as
For arbitrary j and k, equationCan be calculated by a neighbor operator method, and the definition function q (v) isConsider the literature [ S.F.Kuang, H.Y.Chao, Q.Li, Matrix composition with a confined nuclear norm via a patterned simulation, neuro-molding.316 (2018)190-]Proposed semi-orthogonal linear transformation of neighborhood operators ifLL=vI,v>0,Is provided withAccording to the theorem W of Daubechies waveletsTW ═ I, formula proxf(x) Can be changed intoWhereinTo obtainWhereinThus, the formulaCan be further expressed as
6) According to the step 5, the iterative solution step of the proposed objective cost function can be summarized as the following algorithm:
7) the proposed objective cost function, the function model parameters include: coefficient ajβ, and a regularization parameter λjThe three parameter method settings are as follows: satisfies a 0. ltoreq. a in accordance with strict convexity of the objective cost functionj<1/λjWithout setting the coefficient ajSatisfies aj=0.97/λjFor coefficient β and regularization parameter λjNote that when β is 0 and λjNot equal to 0, the target cost function is degenerated into a single wavelet de-noising model, when β not equal to 0 and lambdajThe objective cost function degenerates to a single fully-variant denoising model, 0. According to the literature [ l.dumbgen, a.kovac.extensions of smoothening via tau strings.electron.j.statist.3(2009)41-75.]Coefficient β with a regularization parameter λjCan be arranged asβ=(1-η)βTVRWherein, in the step (A),for wavelet de-noising coefficients, βTVRThe weight coefficient satisfies 0 < η < 1 for the fully variant de-noising coefficient, the weight is set to 0.9 < η < 1 for maximum reduction of noise interference, η is not set to 0.96, according to the Daubechies wavelet Parseval theorem condition WTW is equal to I, and the wavelet denoising coefficient satisfiesAccording to the literature [ l. Dumbgen, a. kovac. extensions of smoothening via tau strings.electron. j. statist.3(2009)41-75.]In conclusion, the total variation denoising coefficient is set toWhere σ is the standard deviation of the background noiseAnd N is the number of sample points. Thus having λj=2.5ησ/2j/2,In practical engineering application, the standard deviation σ of the background noise can be calculated by the observation signal and the healthy vibration signal acquired under the same working environment. However, in many cases, the healthy vibration signals of the equipment are not collected in advance or are difficult to obtain, and in such cases, the healthy vibration signals can be estimated by using the principle of the absolute median difference of the wavelet denoising algorithm, namelyWherein, MAD (y) is the Median Absolute Difference (MAD) with few observed signals, which is expressed as: mad (y) ═ mean [ | yi-median(y)|],i=1,2,...,N。
And 3, carrying out envelope demodulation on the periodic instantaneous pulse signal by using a Hilbert envelope demodulation method, extracting the bearing fault characteristic frequency and frequency multiplication thereof, comparing the extracted bearing fault characteristic frequency with the theoretical fault characteristic frequency, and identifying the position of the bearing fault.
The invention is further illustrated below with reference to specific experimental data:
the invention provides a bearing fault periodic pulse sparse separation and diagnosis method under strong background noise, which comprises the following steps:
1) acceleration sensors are installed in the horizontal direction and the vertical direction of a fault bearing seat of the speed reducer, original vibration signals of the fault bearing in the horizontal direction and the vertical direction are collected, and a schematic diagram of an experiment platform related to the specific embodiment of the invention is shown in fig. 2.
The invention utilizes the outer ring fault of the tapered roller bearing of the input shaft (non-driving end) in the four-stage speed reducer gearbox to verify the effectiveness of the proposed method.
Before the vibration acceleration signal is collected, a groove with the length being about 30% of the width of the tooth root is machined on the outer ring of the detected tapered roller bearing (bearing model FAG-32212-A) by utilizing a linear cutting machining technology. The experimental sampling frequency is 5120Hz, the rotating speed is 1000rpm (16.67Hz), and the sampling sample length is5120 points, according to a bearing outer ring fault frequency formula fBPO=1/2×N×[1-d/D×cosα]Wherein N is the number of the balls, D is the inner diameter of the bearing, D is the outer diameter of the bearing, α is the contact angle, the theoretical fault frequency of the outer ring of the tapered roller bearing can be calculated to be 118.8Hz, and the detailed geometric parameters of the tested bearing are shown in Table 1.
TABLE 1 Experimental bearing geometry parameters tested
2) And randomly selecting a group of vibration acceleration signals in the horizontal direction and the vertical direction as signals to be analyzed. Fig. 3(a) is a time domain waveform of an original vibration acceleration signal in a horizontal direction, and fig. 3(b) is a Hilbert envelope spectrum of the vibration acceleration signal in the horizontal direction; fig. 3(c) is a time domain waveform of the original vibration acceleration signal in the vertical direction, and fig. 3(d) is a Hilbert envelope spectrum of the vibration acceleration signal in the vertical direction. It can be seen from the time domain signal waveform that the fault pulse is submerged in strong external interference noise, transient and periodic cycle characteristics of the fault pulse cannot be observed, and the extraction of the fault frequency is affected by the noise interference frequency distributed seriously around the bearing fault frequency (such as 119.4Hz, 238.8Hz, 120Hz and 239.4Hz) obtained in fig. 3(b) and fig. 3 (d).
3) The original vibration signals in the horizontal direction and the vertical direction are processed by the proposed sparse Daubechies wavelet pulse separation method, and the parameters of the target cost function are set as follows, namely a coefficient β is set to be β ═ 1- η (β)TVRWhereinRegularization parameter λjIs arranged asWhereinThe weighting coefficient is set to η -0.96, the wavelet transform scale is set to j-8, and the coefficient ajIs aj=0.97/λjThe algorithm was executed 50 times. The standard deviation sigma of the noise can be obtainedAnd MAD (y) mean [ | yi-median(y)|]N is estimated, i 1, 2. Finally, horizontal fault periodic pulses and vertical fault periodic pulses are obtained as shown in fig. 4(a) and 4(c), and it can be seen that an obvious instantaneous fault pulse sequence is sequentially separated from an original vibration signal to obtain a pulse interval of 0.0084s, and the pulse interval is matched with the fault frequency of a bearing outer ring. Fig. 4(b) and 4(d) are Hilbert envelope spectrums of the fault periodic pulse signals in the horizontal direction and the vertical direction, and it can be seen that noise interference frequencies around the fault frequency are greatly suppressed, and the fault frequency is more prominent.
The above results show that: the bearing fault periodic pulse sparse separation and diagnosis method under the strong background noise can effectively filter background interference noise irrelevant to fault frequency, can accurately separate out a periodic instantaneous pulse sequence relevant to bearing outer ring faults, and can clearly and prominently detect the bearing outer ring fault characteristic frequency and harmonic frequency of the bearing outer ring fault characteristic frequency by the extracted envelope spectrum, so that the extraction and fault position diagnosis of the periodic fault pulse are realized, and the theoretical effectiveness and the engineering practicability of the method are also proved.
Claims (2)
1. A bearing fault periodic pulse sparse separation and diagnosis method under strong background noise is characterized by comprising the following steps:
step 1, respectively installing acceleration sensors in the horizontal direction and the vertical direction of a bearing seat to be detected, and acquiring a vibration acceleration signal in the horizontal direction and a vibration acceleration signal in the vertical direction of the bearing;
step 2, establishing a target cost function:
in the formula (I), the compound is shown in the specification,representing a wavelet transform coefficient to be estimated; ω represents a wavelet transform coefficient; f (ω) represents the objective cost function; y represents the vibration acceleration signal in the horizontal direction or the vibration acceleration signal in the vertical direction obtained in the step 1; lambda [ alpha ]jRepresenting the regularization parameter at the time scale j; continuous wavelet transform of transform coefficients x: omegaj,k=Wj,kx, in the formula, Wj,kThe wavelet transform is performed on a translation scale j and a time scale k, y is Ax + w, A represents a matrix with Toeplitz, and w represents background noise or interference components; a isjRepresenting a penalty function scale coefficient; phi (omega)j,k;aj) β denotes regularization parameters, D denotes a first order differential matrix;
step 3, inputting the horizontal direction vibration acceleration signals and the vertical direction vibration acceleration signals obtained in the step 1 into the target cost function established in the step 2 respectively, and obtaining the horizontal direction vibration acceleration signals and the vertical direction vibration acceleration signals through iterative calculation of an alternating direction multiplier methodObtaining a horizontal direction periodic fault pulse signal and a vertical direction periodic fault pulse signal through wavelet inverse transformation calculation, and defining the periodic fault pulse signals asThen there is
2. The periodic impulse sparse separation and diagnosis method for bearing faults under strong background noise as claimed in claim 1, further comprising after said step 3:
and carrying out envelope demodulation on the horizontal direction periodic fault pulse signal and the vertical direction periodic fault pulse signal by using a Hilbert envelope demodulation method, extracting bearing fault characteristic frequency and frequency multiplication thereof, comparing the extracted bearing fault characteristic frequency with theoretical fault characteristic frequency, and identifying the fault position of the bearing.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910279626.3A CN110940522A (en) | 2019-04-09 | 2019-04-09 | Bearing fault periodic pulse sparse separation and diagnosis method under strong background noise |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201910279626.3A CN110940522A (en) | 2019-04-09 | 2019-04-09 | Bearing fault periodic pulse sparse separation and diagnosis method under strong background noise |
Publications (1)
Publication Number | Publication Date |
---|---|
CN110940522A true CN110940522A (en) | 2020-03-31 |
Family
ID=69905719
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201910279626.3A Withdrawn CN110940522A (en) | 2019-04-09 | 2019-04-09 | Bearing fault periodic pulse sparse separation and diagnosis method under strong background noise |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN110940522A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111750978A (en) * | 2020-06-05 | 2020-10-09 | 中国南方电网有限责任公司超高压输电公司广州局 | Data acquisition method and system of power device |
CN112098094A (en) * | 2020-09-27 | 2020-12-18 | 上海数深智能科技有限公司 | Method for diagnosing fault vibration of low-speed heavy-load bearing |
CN113804439A (en) * | 2020-06-01 | 2021-12-17 | 株式会社日立大厦系统 | Bearing inspection device and bearing inspection method |
WO2023015855A1 (en) * | 2021-08-10 | 2023-02-16 | 江苏大学 | Generalized autocorrelation method for feature extraction of faults in bearings under variable speed conditions |
-
2019
- 2019-04-09 CN CN201910279626.3A patent/CN110940522A/en not_active Withdrawn
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113804439A (en) * | 2020-06-01 | 2021-12-17 | 株式会社日立大厦系统 | Bearing inspection device and bearing inspection method |
CN111750978A (en) * | 2020-06-05 | 2020-10-09 | 中国南方电网有限责任公司超高压输电公司广州局 | Data acquisition method and system of power device |
CN112098094A (en) * | 2020-09-27 | 2020-12-18 | 上海数深智能科技有限公司 | Method for diagnosing fault vibration of low-speed heavy-load bearing |
WO2023015855A1 (en) * | 2021-08-10 | 2023-02-16 | 江苏大学 | Generalized autocorrelation method for feature extraction of faults in bearings under variable speed conditions |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN110940522A (en) | Bearing fault periodic pulse sparse separation and diagnosis method under strong background noise | |
CN108805059B (en) | Sparse regularization filtering and self-adaptive sparse decomposition gearbox fault diagnosis method | |
Feng et al. | Rolling element bearing fault detection based on optimal antisymmetric real Laplace wavelet | |
CN110046476B (en) | Ternary binary fractal wavelet sparse diagnosis method for rolling bearing faults | |
CN113375939B (en) | Mechanical part fault diagnosis method based on SVD and VMD | |
CN109708891B (en) | Fault diagnosis method for raceway of flexible elliptical bearing | |
Hao et al. | Morphological undecimated wavelet decomposition for fault diagnostics of rolling element bearings | |
CN109655266B (en) | Wind turbine generator bearing fault diagnosis method based on AVMD and spectrum correlation analysis | |
CN109883706A (en) | A kind of rolling bearing local damage Weak fault feature extracting method | |
CN112945546B (en) | Precise diagnosis method for complex faults of gearbox | |
CN104215456A (en) | Plane clustering and frequency-domain compressed sensing reconstruction based mechanical fault diagnosis method | |
CN112985809A (en) | Rolling bearing fault diagnosis method based on signal multi-dimensional fine image | |
CN107966287B (en) | Weak fault feature extraction method for self-adaptive electromechanical equipment | |
Lin et al. | A review and strategy for the diagnosis of speed-varying machinery | |
CN111665050B (en) | Rolling bearing fault diagnosis method based on clustering K-SVD algorithm | |
CN112098093A (en) | Bearing fault feature identification method and system | |
CN114813123A (en) | Rolling bearing weak fault diagnosis method based on PSO-VMD-MCKD | |
Li et al. | A fault diagnosis approach for gears using multidimensional features and intelligent classifier | |
CN113758708B (en) | Rolling bearing signal frequency domain fault diagnosis method based on L1 norm and group norm constraint | |
CN116086807A (en) | Fault judging method for rolling bearing and related product | |
Xia et al. | Convolutional sparse coding with periodic overlapped group sparsity for rolling element bearing fault diagnosis | |
Yu et al. | A clustering K-SVD-based sparse representation method for rolling bearing fault diagnosis | |
CN113639985A (en) | Mechanical fault diagnosis and state monitoring method based on optimized fault characteristic frequency spectrum | |
CN116028840A (en) | Marine rotor fault diagnosis method for maximum overlapped discrete wavelet packet transformation time spectrum | |
CN112161805A (en) | Bearing tiny fault diagnosis method based on time series scale analysis and CNN |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
WW01 | Invention patent application withdrawn after publication | ||
WW01 | Invention patent application withdrawn after publication |
Application publication date: 20200331 |