impact hammer of light structures problem- need help.
impact hammer of light structures problem- need help.
(OP)
Hi, I am using a small impact hammer from kistler 2722A2000
and recently i realize that for the low frequency range I 'am getting a strange autospectrum from the force signal. Instead of getting a nice curve shape (a near horizontal bounce) I get a irregular bouncing curve like this:
http:/ /files.eng ineering.c om/getfile .aspx?fold er=9f8d073 7-553a-434 3-8ed9-636 66d970377& amp;file=m artelo.bmp
This will affect the transfer FRF function.
The attached figure in the above link presents the autospectrum for the load cell of impact hammer and the other curve is from accelerometer, which is nice and clean.
I already checked cables, ICP feeding (through different icp sources as well), tip link, etc. Any ideas about this issue? Any procedure to check anything?
Please help.
Thanks
and recently i realize that for the low frequency range I 'am getting a strange autospectrum from the force signal. Instead of getting a nice curve shape (a near horizontal bounce) I get a irregular bouncing curve like this:
http:/
This will affect the transfer FRF function.
The attached figure in the above link presents the autospectrum for the load cell of impact hammer and the other curve is from accelerometer, which is nice and clean.
I already checked cables, ICP feeding (through different icp sources as well), tip link, etc. Any ideas about this issue? Any procedure to check anything?
Please help.
Thanks





RE: impact hammer of light structures problem- need help.
RE: impact hammer of light structures problem- need help.
On the other hand i understand that softer contact on suspended or foam support can produce some undesired effect.
Any idead?
RE: impact hammer of light structures problem- need help.
RE: impact hammer of light structures problem- need help.
In time signal i see a quite narrow peak but i cann't ensure that this peak is really only one (i will make zoom on that just to check)
Is there any recomendations concerning the trigger? or the rectangular window?
thanks
RE: impact hammer of light structures problem- need help.
M
--
Dr Michael F Platten
RE: impact hammer of light structures problem- need help.
Another trap for young players is leaving Hanning switched on for impact tests.
Cheers
Greg Locock
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