Re : problem in filtering the signal

[mehdi33]

Hi!

I work for a signal processing subject. The objective is to detect vibrations due to the presence of unbalance in a tool holder of a machining center . The tool holder rotates at a speed of 7000 rev / min , I chose a very high sampling frequency of 25 kHz. For filtering the signal I do not know what the cutoff and what type of filter that I will choose! I need your help.

Thanks!

[GerdW]

Hi mehdi,

reading some literature on "balancing of rotating parts" may be of great help here - such stuff tends to get complex…

When you have got some knowledge about this topic you will know what parts of your signal (or which frequencies) are important to you and how to apply filters to your signal!

[mehdi33]

Hi GerdW!

Thank you for your answer.

According to my knowledge of unbalance faults, the primary symptom of unbalance vibration is 1X. Does this mean I have to choose a cutoff frequency nearby the rotation frequency of the tool holder or it must be close to half of the sample rate frequency that I have chosen?

Best regards,

[Dasso]

Hello mehdi,

I think you need some basic order analysis techniques for analyzing sound and vibration signals from rotating  machinery : http://zone.ni.com/reference/en-XX/help/372416A-01/svtconcepts/intro_ord_ana/

and if you want more information about vibration analysis and signal processing in LabVIEW, go at part 6 Wavelet Analysis : http://www.ni.com/white-paper/9230/en/

Bye

Audace MUDRY

[mehdi33]

Hi Audace!

Thank you for these links. Order analysis is the best choice for my case!

Regards,