Optimizing logarithmic decrement damping estimation through uncertainty propagation

This work derives an analytical expression for the optimal number of periods between samples when estimating damping using the logarithmic decrement method. This expression, obtained from an uncertainty analysis of the method's principal equation, is shown to be a function of only one system pa...

Full description

Saved in:
Bibliographic Details
Published in:Journal of sound and vibration 2019-09, Vol.457, p.368-376
Main Authors: Little, Jared A., Mann, Brian P.
Format: Article
Language:English
Subjects:
Damping
Damping ratio
Linear systems
Logarithmic decrement
Numerical analysis
Optimization
Uncertainty
Uncertainty analysis
Uncertainty propagation
Vibration
Viscous damping
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This work derives an analytical expression for the optimal number of periods between samples when estimating damping using the logarithmic decrement method. This expression, obtained from an uncertainty analysis of the method's principal equation, is shown to be a function of only one system parameter: the damping ratio. This suggests that for linear systems with viscous damping there is a unique, damping-dependent period choice corresponding to minimum uncertainty in the estimated damping ratio. This result led to the discovery of a constant optimal amplitude ratio offering a straightforward guideline that can be applied by the experimenter to obtain damping ratio estimates with minimum uncertainty. The derived expressions are applied to a series of numerical and experimental systems to confirm their validity.
ISSN:0022-460X
1095-8568
DOI:10.1016/j.jsv.2019.05.040