srs diadem shock

[Chris_H1]

Great to see that DIAdem 2010 now has a SRS (Shock Response Spectrum) function!  I immediately checked the help to see what algorithm is being used and saw "ISO-Norm 18431-4:2007".  Is this document available as a 1) free download and 2) in English?  Thanks and keep up the great work!! 

[Adam G]

Hello Chris,

We do not have the document that we can give out. You can buy it from www.iso.org. If you get stuck while using the function you can ask us some specific questions about what you are doing and we can assist you from there.

Best Regards,

Adam G 

[Chris_H1]

Hmmm...so, you understand the algorithm that you implemented, but I'm not allowed to know which algorithm you chose to implement unless I part with some of my filthy lucre?  Ha, Ha!!  That's a good one, you almost had me...wait...you can't be serious!!!  I need to PAY to find out which algorithm NI used for SRS in DIAdem?  I find this concept to be most...words fail me at this point.  Most unsatisfying.  That is the mildest term I can come up with at this moment.  Thank you for taking the time to be almost helpful in your answer.

[Brad_Turpin]

Hang on, Chris,

Let's not shoot the messenger here.  Your original post quoted the DIAdem Help system, which exactly specified the name of the SRS method used (ISO-Norm 18431-4:2007).  We didn't invent the method, so we don't own rights to it.  It's not NI's fault if the ISO organization has decided to charge for the documentation.  We are legally obligated not to hand out the document they are selling.

I agree the situation is unsatisfying, but there's not much we can do about it.  Now again, R&D volunteered to answer specific questions that don't require us to send you the documentation, so we're willing to help as much as we legally can here.

Brad Turpin

DIAdem Product Support Engineer

National Instruments

[DRock]

Though we worked through this thread via email, for all future readers who stumble across this thread with the same question as Chris, the algorithm that NI DIAdem uses is the Ramp Invariant (Smallwood) algorithm.

Thanks!

[Chris_H1]

My thanks to all who helped solve this mystery!  Kudos to Derrick, Brad, and Andy!  For future readers let me emphasize that I was NOT asking NI to divulge the "secret inner workings" of the SRS algorithm, rather I was asking which algorithm they had used (i.e. its name).  There are a number of SRS algorithms discussed in the literature, and which one you use can depend upon what industry you are in.  Being given the ISO number in the help file should have been sufficient, however, I was unable to readily link the ISO number to the name of the algorithm via internet search.  I hit the DIAdem discussion forum thinking this was an easy question, after all, LabVIEW proclaims exactly what method it uses in its help file (Smallwood's Ramp Invarient).  NI's initial reply, that they cannot even tell me the NAME of the algorithm they used (without payment to the ISO) I admit I found very unsatisfying.  However, after some additional communication (outside the DIAdem forum) we managed to reach a fully satisfactory arrangement.  Thanks again!
Chris