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How to get Spectral Kurtosis and Kurtogram

I have a dataset for health and faulty bearing vibration. I want to test the signal using Spectral Kurtosis and Kurtogram.

I am using Skewness and Kurtosis VI to get a Kurtosis but its output is not enough to explain faulty bearing. I wanna know if there is any specific block to get Spectral Kurtosis and Kurtogram.

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I had never heard of Spectral Kurtosis (though I could guess that it involved the kurtosis, the 4th moment, of a spectrum), so I looked it up and found it can be used to identify faulty bearings!

 

I'm almost certain that there is no built-in LabVIEW function to do this.  However, if you have the appropriate signal, and know how the SK is computed, you can easily write a VI yourself to obtain this measure.  You'll need to take multiple short-time Fourier Transforms of your signal (at overlapping time points) and then compute the SK from the resulting Spectra.  There are papers describing the techniques on the Web.

 

Bob Schor

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I have got the spectral Kurtosis how could I represent the data in kurtogram. I know there is no built in block diagram and I need to create a new VI but what type of block diagram could be used to represent numbers to colour intensity and how could I represent it in 2d chart.

Kurtogram is a representration of number to colour as shown in picture where red being the highest value and blue representing the lowest value

Kurtogram.png

How could I perform this operation in LABview

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Use a table. You can set the background color of each cell individually. (If you don't show the separators and make some empty and the same color, you can get close to what you want).

 

You can also build it from scratch using a picture indicator. It is easy to draw boxes and text.

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My Kutrosis is 5 level that means the table would be 5*16 and i have to test 15 different dataset on that table that means a total of 1800 variable. Manual selection seems impractical so I would need any technique that could automatically select colour shade.

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The complication is not the table, but the amount of values you seem to want to display. Sorry, I don't understand your math. How do 5 levels translate into 1800 values and how should that look on the front panel? How big is your monitor? 😮

LabVIEW is a full featured programming language and can be taught to select any number of shades automatically and faster than any human (make sure you disable front panel updates during the color setting), so I don't understand your last argument.

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1800 is the result of 15 different results my output would display a 5*16 table.

As you said LabVIEW is a full featured programming language and can be taught to select any number of shades automatically. My question is how to do that. Any example any code or VI

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15x16x5 is 1200.

 

Here is a very simple draft (LV 2015) showing how to populate a table similar to your picture and color each cell based on values and row (row alternate between shades of red, green, blue, while cells get brighter with the random value)

 

Modify as needed.

 

 

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