lang="en-US"UTF-8 Averaging Frequency Response Functions - Prosig Support class="post-template-default single single-post postid-3803 single-format-standard custom-background custom-background-image group-blog blogolife-3_0_7 unknown"

Prosig Support Blog

The place to come for support for Prosig's DATS, P8000 & PROTOR products

Prosig Support Blog
3803class="post-3803 post type-post status-publish format-standard hentry category-signal-processing category-tutorial tag-average tag-averaging tag-frf tag-structural tag-structure"

Averaging Frequency Response Functions From A Structure

fa fa-file-text-o

The following was written by Adrian Lincoln in response to a customer asking about averaging Frequency Response Functions (FRFs)

Further to your reply it should be noted that there is no such mathematical or physical quantity corresponding to an averaged structural FRF except in those special cases where you are testing a symmetric structure comprised of nominally identical components (such as turbine blades). For symmetric structures, where you can impact at a similar position on each component and measure the corresponding acceleration at a similar response position, then the individual FRF’s should have the same characteristics and therefore can be averaged.

For structures that don’t have multiple symmetric components then you should not perform any sort of averaging because the FRF’s will not have the same characteristics. For example, if you have beam-like structure and are measuring the FRF’s between different locations along the beam, then these FRF’s should only be averaged as moduli and not with respect to phase and coherence.

The following two tabs change content below.

Adrian Lincoln

Sound & Vibration Signal Processing Analyst at Prosig
Adrian Lincoln is Signal Processing Technology Manager at Prosig Ltd and has responsibilities for signal processing applications, training and consultancy. He was formerly a Research Fellow at the Institute of Sound & Vibration Research (ISVR) at Southampton University. He is a Chartered Engineer and member of the British Computer Society and Institute of Mechanical Engineers.

Latest posts by Adrian Lincoln (see all)

Share the knowledge:

Adrian Lincoln

Your email address will not be published. Required fields are marked *

Proudly powered byWordPressDesign byBlogoLife