A Normalized Analysis Method for Acoustic Emission Signal Detection of Metal Fracture
An acoustic emission signal and analysis method technology, applied in the field of normalization analysis, can solve the problems of no theoretical basis for the determination of the power adjustment coefficient, no one can propose it, poor flexibility, etc., to achieve ideal results, flexible use, and avoid focus. Effect
Inactive Publication Date: 2017-06-09
CHINA UNIV OF GEOSCIENCES (WUHAN)
View PDF5 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
The method shown in Equation (1) has poor flexibility, and the input signal amplitude or energy directly affects the selection of the c value. At present, no one can propose an effective adaptive threshold selection method, and the useful component amplitude in the actual signal The value and energy are often different or even quite different, so it is easy to eliminate the information item by setting the threshold value to eliminate the cross item; the method shown in formula (2) is slightly improved, but there is no theoretical basis for the determination of the power adjustment coefficient. How to determine the power adjustment coefficient according to the characteristics of the signal to be analyzed needs to be further studied, which will cause inconvenience to use, and at the same time, there will be unavoidable cross-item interference. It is often necessary to further process the obtained signal by filtering and other methods in order to obtain a time that is easy to interpret. Spectrograms and spectrograms
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0030] The present invention will be further described below in conjunction with drawings and embodiments.
[0031] The invention provides a normalized analysis method for the detection of metal fracture acoustic emission signals, combining figure 1 , including the following steps:
[0032] (1) Perform short-time Fourier transform and Wigner-Ville distribution on the acoustic emission signal respectively, and obtain the time-frequency representation STFT array of the acoustic emission signal and the time-frequency distribution WVD array of the acoustic emission signal;
[0033] (2) Select the maximum value max_stft of the STFT array and record its array position (i, j), divide each number in the STFT array by max_stft to normalize the STFT array, and the dimensionless normalized Acoustic emission signal time-frequency representation array STFT_1;
[0034] (3) Record the minimum value min_1 among the non-zero values in the array STFT_1, and replace all the numbers with a va...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention provides a normalized analysis method used for detecting a metal rupture acoustic emission signal. Short-time Fourier transform and Wigner-Ville distribution are respectively performed on the metal rupture acoustic emission signal so that arrays STFT and WVD are obtained; the maximum value in the STFT is selected and the position (i, j) is recorded; the STFT normalized so that an array STFT_1 is obtained; the minimum value in the STFT_1 is recorded and 0 value is substituted by the minimum value; the number of the position (i, j) in the WVD array is selected; the WVD is normalized so that an array A is obtained; an A point is divided by the STFT_1 so that an array B is obtained, the position (i1, j1) of the number greater than the upper limit value in the B is recorded, and numbers greater than the upper limit value and less than the lower limit value in the B are set to 1; the number of the position (i1, j1) in the WVD is set to 0, and the WVD points are divided by B; and the WVD is outputted. Cross term interference can be greatly eliminated, time frequency resolution is relatively high, the result is ideal and use is flexible.
Description
technical field [0001] The invention relates to a normalized analysis method for detecting metal fracture acoustic emission signals, which belongs to the field of earthquake electromagnetic precursor research and earthquake prediction. Background technique [0002] When the material is deformed or subjected to external force, the strain energy is released in the form of stress wave, and the acoustic emission signal of metal cracking is received by the sensor, which needs further analysis and processing. [0003] The traditional STFT-WVD time-frequency analysis method will use the following formula to process the metal cracking acoustic emission signal: [0004] [0005] [0006] The traditional STFT-WVD time-frequency analysis method needs to set the threshold c and the power adjustment coefficients a and b. where c is the cross term elimination threshold of the STFT spectrum. Returns 0 when the value of the STFT spectrum is less than the threshold, and returns 1 if ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): G01V1/30
Inventor 郝国成陈忠昌张伟民程卓
Owner CHINA UNIV OF GEOSCIENCES (WUHAN)