Posted ByJose Olvera on February 05, 2003 at 16:17:21:
In Reply to: Re: Envelope Theorem posted byJosé Antonio on August 11, 2002 at 18:45:22:
: Hi again.
: I'm a student of systems engineering in Caracas-Venezuela. I'm developing my thesis based on detecting problems on rotary machines, analyzing the vibrations they produce. I'm using ALL the papers you have published on this page, and now I'm stuck trying to calculate the enveloped of the vibration signal I receive from my accelerometer. I'm using the Hilbert transform in order to do this..but comparing with your results, my graphics are very different and don't show the picks when there is a problem on the machine.
: I would really appreciate your help in order to determine the correct envelope of my signal...what knid of algorithms do you use?..where can I get it?
: Thanx
: Greetings.
: José Antonio S.
: : : Hi.
: : : I don't understand the envelope analisys you made to the signals....Where can i find the mathematical formulas for doing this??
: : : thanx
: : The most common purpose for envelope detection is for the diagnostics of bearings by measuring the low frequency variations of high frequeny signals. In hardware envelope detection systems, a high frequency band that is expected to have the broadband signals the bearings produce as a result of friction and impqct forces is selected by filtering and then demodulated by rectification, after which the signal is passed through a low pass filter to select the desired signals. There are several ways to do this mathmatically that are used in digital demodulation systems.