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Calculate the time of occurance and period of a disturbance in a signal

Hello All,

I need some guidelines and help for the LabVIEW programming to process a signal.
The attached file contains the signal.
I wish to analyse the signal with following points:
1. Each part of a signal should be analysed.
2. The reference signal should be generated based on the adaption of previous signal patterns.
3. And it should identify the variaion in the signal pattern and note down the time when it is occuring (T) and also the period for which it has occured (t) .
4. The reference signal pattern should not consider the signal with disturbcance.

For example:
Signal Sample for Disturbance 001.JPGIn attached image, the fisrt signal pattern should be considered as a reference pattern and then it should verify the second signal pattern. If there is not much variation in both of them, the reference signal should adapt a pattern based on both of them. Now this new reference signal pattern should be compared to the third signal. The time (T) where is a considerable variation in the signal pattern should be captured (here T=0.338 Sec). Also the duration for which there is a disturbance (delta t) should be captured.
Now for further analysis, the reference pattern should not consider the disturbance signal and compare the forth signal for any disturbance and note down the values if there is again a disturbance.

Thank you in advance for your kind assistance.

Kind regards,
Rahul

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Sorry,
here is the required signal.
The previous file contains two signals.

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The tricky part is to define what is a disturbance 😉

First do once  a correlation to find and correct a shift in the signal

Look at the (absolute or squared) difference of both signals and define a threswhold and use the threshold detector vi

from the point location(s) calculate the time and log it.

And have a look at the waveform monitoring vis....

Greetings from Germany
Henrik

LV since v3.1

“ground” is a convenient fantasy

'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'


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Hi, 

 

there are several options/tools which could work for you.

 

1. Mask and Limit Testing Express VI

2. Threshold Detector: http://zone.ni.com/reference/en-XX/help/371361K-01/ptbypt/threshold_peak_detector_pt/

3. Nonlinear Curve Fit 

4. Manual point to point compareison with defined threshold (i think you have to seperate your Data, so they have allways the same size like your "pattern")

5. Find all minima/maxima and compare with number of minima/maxima in your pattern

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