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Learn About Vibrations!


The ABRAVIBE blog is where you find all the resources for learning more about vibrations. Browse and download examples for the free MATLAB/Octave ABRAVIBE toolbox. Or browse the many theory examples, videos, and resources for the book "Noise and Vibration Analysis: Signal Analysis and Experimental Procedures," by Anders Brandt!

Theory problem: forced response of SDOF system to harmonic excitation by Laplace transform

Theory Examples Posted on Feb 26, 2013 20:21

This an example of using the Laplace
transform to solve the forced response of a mechanical system. It is
also an illustration of the so-called beating phenomenon that can occur
if a dynamic system is suddenly exposed to a harmonic excitation close
to a natural frequency of the system. As illustrated by this example,
the beating phenomenon occurs is more pronounced when damping is low.
The supplied zip file contains a pdf file with the problem definition,
and a separate zip file with a suggested solution. I run this example with all my mechanical vibration students, since it is a good example of how to use the Laplace transform to solve forced response. It is, of course, also an important demonstration example to run for different system damping and excitation frequencies, to learn the concept of beating and to understand the harmonic response of a SDOF system. Download the file by signing in and selecting it on the download page. Or, if you are signed-in already, click on the link in the text above!

Have you missed the chapter examples supplied with the ABRAVIBE toolbox?

ABRAVIBE Examples Posted on Feb 26, 2013 19:44

We have noticed from some support questions, that some ABRAVIBE toolbox users seem to have missed the wealth of examples supplied with the ABRAVIBE toolbox. To ensure you are not one of those, I would like to make clear that after installing the ABRAVIBE toolbox (i.e. unzipping the content to a directory of your choice), there will be a directory called ChapterExamples. Usually this will be located in the Abravibe_Toolbox directory which you unzipped, unless you altered it during unzipping.

The ChapterExamples inlcudes a subdirectory for each chapter (2 to 16) of the book “Noise and Vibration Analysis“, in which are located a large number of examples of various ABRAVIBE applications of the theory covered by that chapter. If you are not a proud owner of the book, you should not fool yourself by not browsing through these subdirectories! Regardless of whether you have the book or not, these subdirectories includes examples of many common tasks you may want to use the ABRAVIBE toolbox for, so they will help you get quickly started using the toolbox!