Vibration analysis

[irfan789]

do i need to double integrate the signal even if i get an accelorometer signal from NI sound and vibration signal simulator box ?

[RPJ]

I wonder if by this time NI came with a vi that does just that gets in acceleration signal from a vibration sensor and provide as output the speed and the displacement. Anybody?

Thank you

[joost]

You can use a straight accel signal for vibration monitoring and analysis - that is actually a common way to do such monitoring. Double integration would mean you transfer to the displacement domain. This is hardly ever needed/interesting as the higher frequency content is so strongly suppressed in a displacement signal.

What are you monitoring?

[preston_johnson]

The Sound and Vibration Measurement Suited on-line manuals have some great tutorial information:

http://zone.ni.com/reference/en-XX/help/372416C-01/

see the concepts section

http://zone.ni.com/reference/en-XX/help/372416C-01/TOC1.htm

If you wish to purchase an excellent set of working sound and vibrarion measurement vis, with out of the box working examples for vibration monitoring, balancing, and frequency response, these are available as the Sound and Vibration Measurement Suite.  Otherwise, you can build up the functions you need in regular LabVIEW.  Following the concepts from the manual should be a big help. 

Regards,

Preston

[RPJ]

I know. However, sometimes you just need it...

A lot of water went down the river since I started working more intesively with vibrations. I have a much better sense now.

[RPJ]

Thank you, Preston.

I believe the "getting displacement from acceleration" vi should be in the basic set of tools.

Just a personal opinion.

[irfan789]

i am doing this task using sbRIO9642 and sound and vibration signal simulator box  (in search of manual) on RealTime

control the harmonics of the vibrations obtained from the  sound and vibration signal simulator box

parameters:.... x and y acclerations from the box are obtained but  failed to  make the harmonic analysis

next tried to obtain the "TACH OUT " signal from the box so that i can measure the speed 

i wanted to know  is tach out a digital or analog value and how should i count the number of pulses (implemeting a counter? or using a up counter)

so that i can measure the speed 

and i also have tried on FPGA to do the same but unable to get the exact count value...

below are few codes which i tried on fpga 

i am getting negative values in the count indicator...for the code integer.png