Nothing Special   »   [go: up one dir, main page]

CN108398260B - Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method - Google Patents

Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method Download PDF

Info

Publication number
CN108398260B
CN108398260B CN201810022238.2A CN201810022238A CN108398260B CN 108398260 B CN108398260 B CN 108398260B CN 201810022238 A CN201810022238 A CN 201810022238A CN 108398260 B CN108398260 B CN 108398260B
Authority
CN
China
Prior art keywords
signal
angular velocity
instantaneous angular
probability density
spectrum
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.)
Active
Application number
CN201810022238.2A
Other languages
Chinese (zh)
Other versions
CN108398260A (en
Inventor
童水光
黄元媛
从飞云
童哲铭
张依东
唐宁
余跃
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN201810022238.2A priority Critical patent/CN108398260B/en
Publication of CN108398260A publication Critical patent/CN108398260A/en
Application granted granted Critical
Publication of CN108398260B publication Critical patent/CN108398260B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M13/00Testing of machine parts
    • G01M13/02Gearings; Transmission mechanisms
    • G01M13/021Gearings
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01MTESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M13/00Testing of machine parts
    • G01M13/02Gearings; Transmission mechanisms
    • G01M13/028Acoustic or vibration analysis

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)

Abstract

The invention provides a method for quickly evaluating the instantaneous angular speed of a gearbox based on a mixed probability method, which comprises the following steps of: collecting acoustic emission signals and vibration acceleration signals; denoising the signal by a wavelet threshold; normalizing the denoised signal; performing pre-whitening processing on the normalized signal by adopting a cepstrum editing method; carrying out Gabor conversion to obtain a spectrogram of the mixed signal; regarding each column of the mixed spectrogram as an instantaneous spectrum, and establishing a probability density function of the instantaneous angular velocity at each time step; combining all probability density functions within a given time interval into one; performing Gaussian smoothing processing on the obtained probability density function; and obtaining the change rule of the angular speed along with time. The invention does not need to use a rotating speed measuring instrument, improves the system stability under severe working conditions and saves the cost; the limitation of the rotation speed change on the rotation speed evaluation is separated, and the rotation speed can still be accurately identified under the condition of severe rotation speed change.

Description

Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method
Technical Field
The invention relates to the technical field of signal processing of rotating machinery, in particular to a method for quickly evaluating instantaneous angular speed of a gearbox based on a mixed probability method.
Background
The gearbox is an important speed change and power transmission component, is widely applied to modern industrial equipment, and has important significance for safety production of enterprises when condition monitoring and fault diagnosis are carried out on the gearbox. In the fault diagnosis of gearboxes, especially in variable-speed operating conditions, the speed estimation is an indispensable component thereof. The most widely used method for estimating the rotating speed at present is to measure the rotating speed by installing a tachometer. However, for an industrial field with a severe operating environment, the additional installation of a tachometer greatly reduces the reliability of system equipment. In addition, the installation of the tachometer requires additional design of the device and adds considerable cost.
The technical search shows that the existing tachometer-free rotating speed estimation method is based on the analysis of vibration signals of a gearbox body. The frequency domain or time-frequency domain conversion is carried out on the vibration signals, the meshing frequency at each moment is extracted, and the number of teeth of the gear is combined, so that the rotating speed of the gear box is determined. However, the field operation environment of the equipment is generally severe, the vibration signal of the actual measurement gearbox box usually contains a large amount of noise components and other harmonic interference components, and particularly under the working condition of variable rotating speed, the frequency spectrum fuzzy phenomenon is easy to occur when the meshing frequency at each moment is extracted. In addition, the existing method is only suitable for occasions with small fluctuation range of the rotating speed, and some estimation algorithms are complex and cannot meet the requirement of rapidly realizing rotating speed estimation on an industrial field.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: aiming at the defects of the prior art, the method for rapidly evaluating the instantaneous angular speed of the gearbox based on the mixed probability method is provided, and the angular domain signals are resampled without using complex hardware or even a velocimeter.
Therefore, the invention adopts the following technical scheme: the method for quickly evaluating the instantaneous angular speed of the gearbox based on the mixed probability method comprises the following steps:
(1) respectively placing an acceleration sensor and an acoustic emission sensor on the gearbox body, and acquiring an acceleration signal and an acoustic emission signal of the gearbox body;
(2) denoising and smoothing the acquired acoustic emission signals and vibration acceleration signals by adopting a wavelet threshold method;
(3) respectively carrying out normalization processing on the denoised acoustic emission signal and the denoised vibration acceleration signal;
(4) carrying out pre-whitening treatment on the normalized acoustic emission signal and the vibration acceleration signal, improving the impact characteristic of the signal and removing the resonance of the structure;
(5) after pre-whitening treatment, carrying out Gabor transformation on the acoustic emission signal and the vibration acceleration signal to obtain a spectrogram of a mixed signal;
(6) each column of the mixed spectrogram is considered as a transient spectrum, while taking into account the first 10 harmonic volumes generated by each impulse, in order to establish a probability density function of the instantaneous angular velocity at each time step:
Figure BDA0001543911160000011
where ω is set as a parameter of the probability density function, Ω is the instantaneous angular velocity, Hi(i∈[1...n]) Is the sequence of impact events, A (H)iω) is the temporal spectrum, ζ, of the signal after pre-whiteningiIs a normalization factor, ΩminAnd ΩmaxIs the minimum and maximum of the apriori instantaneous angular velocity law;
(7) introducing a continuity condition, and combining all probability density functions in a given time interval into one:
Figure BDA0001543911160000012
(8) carrying out smoothing treatment on the obtained probability density function;
(9) and extracting the expected value of the probability density function in each time step to obtain the final angular speed change rule along with the time.
Further, the sequence of events during operation of the gearbox that can lead to a strong vibratory impulse response is known.
Further, the wavelet threshold denoising main steps in the step 2) are as follows:
(2.1) carrying out wavelet decomposition on the collected acoustic emission signals and acceleration signals to obtain each scale coefficient;
(2.2) processing the threshold value, and determining a high threshold value and a low threshold value;
and (2.3) performing wavelet reconstruction on the signals to obtain the denoised signals.
Further, step 3) adopts 0 mean normalization to normalize the signal, i.e. normalize the original data set into a data set with mean 0 and variance 1.
Further, step 4) uses cepstrum editing to implement pre-whitening of the signal, and the specific implementation steps are as follows:
(4.1) carrying out fast Fourier transform on the normalized acoustic emission signal and the normalized vibration acceleration signal to respectively obtain a logarithmic amplitude spectrum and a phase spectrum;
(4.2) carrying out fast Fourier inverse transformation on the logarithmic magnitude spectrum to obtain a real cepstrum;
(4.3) editing the real cepstrum, namely, setting the corresponding inverse harmonic in the real cepstrum to zero to remove the discrete frequency component in the signal;
(4.4) carrying out fast Fourier transform on the edited real cepstrum to obtain an edited logarithmic amplitude spectrum;
(4.5) recombining the edited log-magnitude spectrum with the original log spectrum to form a complex log spectrum;
and (4.6) carrying out inverse Fourier transform on the complex frequency spectrum to obtain a pre-whitened signal of the original signal.
Further, the normalization factor in step 6) is calculated by the following formula:
Figure BDA0001543911160000021
further, the continuity condition in step 7) needs to satisfy the following formula:
Figure BDA0001543911160000022
wherein omegajProbability density function, σ, representing instantaneous angular velocity at the jth time stepk=|γkΔt|,ΔtIs the time step of the spectrum and gamma is the standard acceleration of the instantaneous angular velocity.
Further, step 8) adopts gaussian smoothing, and the specific calculation formula is as follows:
Figure BDA0001543911160000023
wherein the setting j and j + k are gearsTwo moments during the operation of the tank, k representing the time interval between the two moments, then the probability density function [ omega ] of the instantaneous angular velocity at moment jj]j+kIs a probability density function [ omega ] of the instantaneous angular velocity through the moment j + kj+k]Convolution with a Gaussian function, so that the probability density function [ omega ] of the instantaneous angular velocity at time jj]j+kIs j + K (K e-K, …, K) before and after time j]) The result of the co-action of the probability density functions at the time of day.
The invention has the beneficial effects that: the method improves the system stability under the severe working condition and saves the cost; the limitation of the rotation speed change on the rotation speed evaluation is separated, and the rotation speed can still be accurately identified under the condition of severe rotation speed change.
Drawings
FIG. 1 is a flow chart of the evaluation method of the present invention.
Fig. 2 is a flow chart of implementing a pre-whitening process using cepstral editing.
FIG. 3 is a collected acceleration signal for a gearbox.
FIG. 4 is an acoustic emission signal of a gearbox collected.
Fig. 5 is a spectral diagram of a mixed signal.
Fig. 6 is a graph of the angular velocity change obtained finally.
Detailed description of the preferred embodiments
The technical solution of the present invention is further described in detail with reference to the following examples, which are carried out under the premise of the technical solution of the present invention, and detailed embodiments and specific procedures are given, but the scope of the present invention is not limited to the following examples.
The embodiment is to evaluate the rotating speed of a large-range rotating speed changing process of a certain spur gear gearbox test bed, wherein the evaluation process is shown in fig. 1 and specifically comprises the following steps:
1) an acceleration sensor and an acoustic emission sensor are respectively arranged on the gearbox body, and acceleration signals and acoustic emission signals of the gearbox body are acquired, as shown in figures 3 and 4.
2) Denoising and smoothing the collected acoustic emission signals and vibration acceleration signals by adopting a wavelet threshold method, and specifically comprising the following steps of: carrying out wavelet decomposition on the collected acoustic emission signals and acceleration signals to obtain each scale coefficient; processing the threshold value, and determining a high threshold value and a low threshold value; and performing wavelet reconstruction on the signal to obtain a denoised signal.
3) And respectively carrying out normalization processing on the denoised acoustic emission signal and the denoised vibration acceleration signal, wherein a 0-mean normalization method is adopted in the invention, namely, an original data set is normalized into a data set with a mean value of 0 and a variance of 1.
4) The normalized acoustic emission signal and the vibration acceleration signal are subjected to pre-whitening processing, the impact characteristic of the signal is improved, and the resonance of the structure is removed, the pre-whitening is realized by adopting cepstrum editing, the flow chart of the method is shown in figure 2, and the method specifically comprises the following steps:
a. carrying out fast Fourier transform on the normalized acoustic emission signal and the vibration acceleration signal to respectively obtain a logarithmic amplitude spectrum and a phase spectrum;
b. carrying out fast Fourier inverse transformation on the logarithmic amplitude spectrum to obtain a real cepstrum;
c. editing the real cepstrum, namely setting corresponding inverse harmonics in the real cepstrum to zero so as to remove discrete frequency components in the signal;
d. carrying out fast Fourier transform on the edited real cepstrum to obtain an edited logarithmic amplitude spectrum;
e. recombining the edited log-amplitude spectrum with the original log spectrum to form a complex log spectrum;
f. the complex spectrum is inverse fourier transformed to obtain a pre-whitened signal of the original signal.
5) After the pre-whitening processing, Gabor conversion is performed on the acoustic emission signal and the vibration acceleration signal to obtain a spectrogram of the mixed signal, as shown in fig. 5.
6) Each column of the spectrogram is considered as an instantaneous spectrum, while taking into account the first 10 harmonic volumes generated by each impulse, in order to establish a probability density function of the instantaneous angular velocity at each time step:
Figure BDA0001543911160000031
where Ω is the instantaneous angular velocity Hi(i∈[1…n]) Is the sequence of impact events with respect to instantaneous angular velocity, A (f) is the whitened version of the instantaneous spectrum of the response signal, ΩminAnd ΩmaxIs the minimum and maximum values of the law of instantaneous angular velocity a priori, ζiIs a normalization factor and can be calculated by the following formula:
Figure BDA0001543911160000032
7) introducing a continuity condition, and combining all probability density functions in a given time interval into one:
Figure BDA0001543911160000041
8) and performing Gaussian smoothing on the obtained probability density function, wherein the specific calculation formula is as follows:
Figure BDA0001543911160000042
wherein the probability density function [ omega ] of the instantaneous angular velocity at time jj]j+kIs a probability density function [ omega ] of the instantaneous angular velocity through the moment j + kj+k]And convolution with a gaussian function. Therefore, the probability density function [ omega ] of the instantaneous angular velocity at time jj]j+kIs j + K (K e-K, …, K) before and after time j]) The result of the co-action of the probability density functions at the time of day.
9) The expected value of the probability density function is extracted in each time step to obtain the final angular velocity time-dependent law, as shown in fig. 6.
10) The angular velocity variation curve is highly matched with the angular velocity variation curve directly measured by the angular encoder, so that the correctness of the method provided by the invention can be proved.
From the above examples, it can be seen that the method for rapidly estimating the instantaneous angular velocity of the gearbox based on the hybrid probability method provided by the invention is very suitable for rapidly estimating the angular velocity of the gearbox, and can also identify the angular velocity very accurately when the rotating speed is changed in a large range.

Claims (7)

1. The method for quickly evaluating the instantaneous angular speed of the gearbox based on the mixed probability method is characterized by comprising the following steps of: the rapid evaluation method comprises the following steps:
(1) respectively placing an acceleration sensor and an acoustic emission sensor on the gearbox body, and acquiring an acceleration signal and an acoustic emission signal of the gearbox body;
(2) denoising and smoothing the acquired acoustic emission signals and vibration acceleration signals by adopting a wavelet threshold method;
(3) respectively carrying out normalization processing on the denoised acoustic emission signal and the denoised vibration acceleration signal;
(4) carrying out pre-whitening treatment on the normalized acoustic emission signal and the vibration acceleration signal, improving the impact characteristic of the signal and removing the resonance of the structure;
(5) after pre-whitening treatment, carrying out Gabor transformation on the acoustic emission signal and the vibration acceleration signal to obtain a spectrogram of a mixed signal;
(6) each column of the mixed spectrogram is considered as a transient spectrum, while taking into account the first 10 harmonic volumes generated by each impulse, in order to establish a probability density function of the instantaneous angular velocity at each time step:
Figure DEST_PATH_FDA0001543911150000011
where ω is set as a parameter of the probability density function, Ω is the instantaneous angular velocity, Hi(i∈[1...n]) Is the sequence of impact events, A (H)iω) is the temporal spectrum, ζ, of the signal after pre-whiteningiIs a normalization factor, ΩminAnd ΩmaxIs the minimum and maximum of the apriori instantaneous angular velocity law;
(7) introducing a continuity condition, and combining all probability density functions in a given time interval into one:
Figure DEST_PATH_FDA0001543911150000012
(8) carrying out smoothing treatment on the obtained probability density function;
(9) extracting expected values of the probability density function in each time step to obtain a final angular speed time-varying rule;
the continuity condition needs to satisfy the following formula:
Figure DEST_PATH_FDA0001543911150000022
wherein omegajProbability density function, σ, representing instantaneous angular velocity at the jth time stepk=|γkΔt|,ΔtIs the time step of the spectrum and gamma is the standard acceleration of the instantaneous angular velocity.
2. Method for the rapid evaluation of the instantaneous angular velocity of a gearbox based on a hybrid probability method according to claim 1, characterized in that the sequence of events during the operation of the gearbox that lead to strong vibratory impulse responses is known.
3. The method for rapidly evaluating the instantaneous angular velocity of the gearbox based on the mixed probability method as claimed in claim 1, wherein the wavelet threshold denoising in the step 2) mainly comprises the following steps:
(2.1) carrying out wavelet decomposition on the collected acoustic emission signals and acceleration signals to obtain each scale coefficient;
(2.2) processing the threshold value, and determining a high threshold value and a low threshold value;
and (2.3) performing wavelet reconstruction on the signals to obtain the denoised signals.
4. The method for rapidly estimating the instantaneous angular velocity of a gearbox based on the mixed probability method as claimed in claim 1, wherein step 3) normalizes the signal by 0-mean normalization, i.e. normalizes the original data set into a data set with a mean value of 0 and a variance of 1.
5. The method for rapidly evaluating the instantaneous angular velocity of the gearbox based on the mixed probability method according to the claim 1, characterized in that the step 4) uses cepstrum editing to realize the pre-whitening of the signal, and the specific implementation steps are as follows:
(4.1) carrying out fast Fourier transform on the normalized acoustic emission signal and the normalized vibration acceleration signal to respectively obtain a logarithmic amplitude spectrum and a phase spectrum;
(4.2) carrying out fast Fourier inverse transformation on the logarithmic magnitude spectrum to obtain a real cepstrum;
(4.3) editing the real cepstrum, namely, setting the corresponding inverse harmonic in the real cepstrum to zero to remove the discrete frequency component in the signal;
(4.4) carrying out fast Fourier transform on the edited real cepstrum to obtain an edited logarithmic amplitude spectrum;
(4.5) recombining the edited log-magnitude spectrum with the original log spectrum to form a complex log spectrum;
and (4.6) carrying out inverse Fourier transform on the complex log spectrum to obtain a pre-whitened signal of the original signal.
6. The method for fast estimation of instantaneous angular velocity of a gearbox based on the hybrid probability method as claimed in claim 1, wherein the normalization factor in step 6) is calculated by the following formula:
Figure DEST_PATH_FDA0001543911150000021
7. the method for rapidly evaluating the instantaneous angular velocity of a gearbox based on a hybrid probability method according to claim 1, wherein step 8) adopts Gaussian smoothing, and the specific calculation formula is as follows:
Figure DEST_PATH_FDA0001543911150000023
wherein j and j + k are two moments in the operation of the gearbox, and k represents the time interval between the two moments, then the probability density function [ omega ] of the instantaneous angular velocity at the moment jj]j+kIs a probability density function [ omega ] of the instantaneous angular velocity through the moment j + kj+k]Convolution with a Gaussian function, so that the probability density function [ omega ] of the instantaneous angular velocity at time jj]j+kIs j + K (K e [ -K., K.) before and after time j]) The result of the co-action of the probability density functions at the time of day.
CN201810022238.2A 2018-01-10 2018-01-10 Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method Active CN108398260B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810022238.2A CN108398260B (en) 2018-01-10 2018-01-10 Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810022238.2A CN108398260B (en) 2018-01-10 2018-01-10 Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method

Publications (2)

Publication Number Publication Date
CN108398260A CN108398260A (en) 2018-08-14
CN108398260B true CN108398260B (en) 2021-10-01

Family

ID=63094685

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810022238.2A Active CN108398260B (en) 2018-01-10 2018-01-10 Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method

Country Status (1)

Country Link
CN (1) CN108398260B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110595751B (en) * 2019-09-19 2020-12-18 华东理工大学 Early fault characteristic wavelet reconstruction method guided by Gini index and application thereof
CN110633686B (en) * 2019-09-20 2023-03-24 安徽智寰科技有限公司 Equipment rotating speed identification method based on vibration signal data driving
CN110674375A (en) * 2019-09-25 2020-01-10 联想(北京)有限公司 Data processing method and electronic equipment
CN113761466B (en) * 2021-09-09 2022-08-02 北京科技大学 Method and device for constructing vibration signal order ratio spectrum of rotary machine

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105699964A (en) * 2016-02-29 2016-06-22 无锡南理工科技发展有限公司 Road multi-target tracking method based on automobile anti-collision radar
CN107544067A (en) * 2017-07-06 2018-01-05 西北工业大学 One kind is based on the approximate Hypersonic Reentry Vehicles tracking of Gaussian Mixture

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5961950B2 (en) * 2010-09-15 2016-08-03 ヤマハ株式会社 Audio processing device
CN105634634B (en) * 2016-01-29 2018-04-13 北京邮电大学 A kind of asynchronous channel cognitive method there are unknown timing
CN105956574A (en) * 2016-05-17 2016-09-21 重庆交通大学 Rolling bearing service life state same-scale characterization and recognition method under different rotating speeds
CN106780508A (en) * 2016-09-23 2017-05-31 北京联合大学 A kind of GrabCut texture image segmenting methods based on Gabor transformation

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105699964A (en) * 2016-02-29 2016-06-22 无锡南理工科技发展有限公司 Road multi-target tracking method based on automobile anti-collision radar
CN107544067A (en) * 2017-07-06 2018-01-05 西北工业大学 One kind is based on the approximate Hypersonic Reentry Vehicles tracking of Gaussian Mixture

Also Published As

Publication number Publication date
CN108398260A (en) 2018-08-14

Similar Documents

Publication Publication Date Title
CN107505135B (en) Rolling bearing composite fault extraction method and system
CN108398260B (en) Method for quickly evaluating instantaneous angular speed of gearbox based on mixed probability method
Yan et al. Improved Hilbert–Huang transform based weak signal detection methodology and its application on incipient fault diagnosis and ECG signal analysis
CN110617964A (en) Synchronous compression transformation order ratio analysis method for fault diagnosis of rolling bearing
CN109855874B (en) Random resonance filter for enhancing detection of weak signals in vibration assisted by sound
CN109883706B (en) Method for extracting local damage weak fault features of rolling bearing
CN108871742B (en) Improved key-phase-free fault feature order extraction method
CN110779724B (en) Bearing fault diagnosis method based on frequency domain group sparse noise reduction
CN112101245A (en) Short-time Fourier transform mechanical impact feature extraction method based on frequency domain window function
CN110044610A (en) Gear failure diagnosing method
Zhao et al. Synchro-reassigning scaling chirplet transform for planetary gearbox fault diagnosis
Wu et al. A modified tacho-less order tracking method for the surveillance and diagnosis of machine under sharp speed variation
CN108388839A (en) A kind of strong fluctuation of speed feature extracting method based on second order sync extraction transformation
Lv et al. Generalized synchroextracting-based stepwise demodulation transform and its application to fault diagnosis of rotating machinery
CN112380671A (en) General amplitude demodulation method for gear fault vibration modulation signal
Zhang et al. Wind turbine planetary gearbox fault diagnosis via proportion-extracting synchrosqueezing chirplet transform
Yang et al. Resampling technique-based demodulation analysis for planet bearing cage fault diagnosis under nonstationary conditions
CN116625681A (en) Spectral amplitude modulation rolling bearing fault diagnosis method based on short-time Fourier transform
CN114487804A (en) GIS abnormal sound defect detection method and device
CN116304648B (en) Gear fault identification method based on optimized pulse enhancement and envelope synchronous averaging
CN109916624B (en) Hilbert yellow-based fatigue failure diagnosis method for ball screw pair
CN112465068A (en) Rotating equipment fault feature extraction method based on multi-sensor data fusion
CN115356108A (en) Method and device for diagnosing mechanical fault of modulation high-order horizontal extrusion transformation
CN110595751B (en) Early fault characteristic wavelet reconstruction method guided by Gini index and application thereof
CN103308306A (en) Cycloid bevel gear fault diagnosing method based on MESEM and FFT (fast Fourier transform)

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
GR01 Patent grant
GR01 Patent grant