PolyReference/PolyMAX and Agilent 35670A
PolyReference/PolyMAX and Agilent 35670A
(OP)
I have an Agilent 35670A. I carried out impact hammer tests and tried to find out the resonance frequencies of a simple structure (http://www .eng-tips. com/viewth read.cfm?q id=253310& amp;page=1). Someone replied that "...no-one uses curve fits to the Nyquist plot any more for modal analysis (because it doesn't work very well when you have modes close together). These days it is all done using advanced multi-degree of freedom algorithms like Polyreference and PolyMAX." I have zero knowledge in Polyreference or PolyMAX. I wonder whether I could use the data measured by Agilent 35670A to obtain plots derived using Polyreference/PolyMAX algorithms. Could I? If yes, what are the measured data that I need for Polyreference or PolyMAX analysis?
Thank you very much
Thank you very much





RE: PolyReference/PolyMAX and Agilent 35670A
However I suspect the real problem is that with such light symmetrical structure the mode shapes will rotate around and follow your accelerometer.
Your circle fit looks like a good start, but you need to increase the frequency resolution by at least a factor of 2.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: PolyReference/PolyMAX and Agilent 35670A
Thanks for your reply.
You mentioned that "... with such light symmetrical structure the mode shapes will rotate around and follow your accelerometer". I do not fully understand the underlined part. Would you please kindly advise?
I will try to increase the frequency resolution. However, if I'm not mistaken, I already used the highest allowable frequency resolution for Agilent 35670A, i.e. 1600-line, for those measurements. I will check again.
RE: PolyReference/PolyMAX and Agilent 35670A
You have all the tools.
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.