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jenz
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simulated shaft centerline plot

Hi,

 

I try to simulate data for using the "Shaft Centerline ExpressVI" (NI Sound and Vibration). But my "Shaft Centerline Plot ExpressVI (sim).vi" doesn't work and I don't know why :smileysad:

 

The ExpressVI shows no plot and the error massage "The input signal is empty." appears.

 

Has one of you an idea?

 

Thanks

Jens

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Re: simulated shaft centerline plot

Speed profile is not likely sampled at the proper interval (at tachometer pulse positions). Please post back if you can verify sampling or need help converting speed profile to speed position info.

 

The speed waveform is also missing required attributes. Please refer to the generated code for the Tachometer Processing Express VI for how to attach all required attributes. (specifically OAT Convert Speed XY Graph to Waveform.vi)

 

Are you trying to simulate signals because the analog tachometer signal is not available and saved, or because you are trying to input simulated data into the Shaft Centerline Express VI?

Doug
NI Sound and Vibration
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preston_johnson
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Re: simulated shaft centerline plot

have you tried the example:

LabVIEW\examples\order analysis\shaft centerline plot

In your eample, your speed profile should have at least one speed instance per revolution, not sure if this makes a difference. 

Preston Johnson
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Condition Monitoring Systems
Vibration Analyst III - www.vibinst.org, www.mobiusinstitute.com
National Instruments
preston.johnson@ni.com
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www.ni.com/soundandvibration
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jenz
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Re: simulated shaft centerline plot


dsb@NI wrote:

Speed profile is not likely sampled at the proper interval (at tachometer pulse positions).


What do you mean with "at the proper interval"? And how can I change it?

The data I'm using is generated by the S&V-example "oax_Load Shaft Centerline Data.vi".

 


dsb@NI wrote:

Please post back if you can verify sampling or need help converting speed profile to speed position info.


Yes, I need help in converting the speed profile.

 


dsb@NI wrote:
The speed waveform is also missing required attributes. Please refer to the generated code for the Tachometer Processing Express VI for how to attach all required attributes. (specifically OAT Convert Speed XY Graph to Waveform.vi)

Do you mean the following attributes?

missing attributes?

 


dsb@NI wrote:
Are you trying to simulate signals because the analog tachometer signal is not available and saved, or because you are trying to input simulated data into the Shaft Centerline Express VI?

I need the possibility to simulated shaft centerline plots on my desk. But not like the Example "Shaft Centerline Plot (Simulated).vi from the S&V-libary. I want to generate data by myself, with different speeds and offsets (shaft centerline motions), so that I can proof that the algorithm works correctly.

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jenz
Posts: 17
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Re: simulated shaft centerline plot


preston johnson wrote:

have you tried the example:

LabVIEW\examples\order analysis\shaft centerline plot


Yes I tried the example. But I want to program a shaft centerline plot with my own data. On this way I want to proof that the algorithm works correctly.

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jenz
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Re: simulated shaft centerline plot

... that is what I need :smileyhappy:

 

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