PyOMA

This software was created to perform output-only modal identification (Operational Modal Analysis, OMA).

OMA allows the experimental estimation of the modal parameters (natural frequencies, mode shapes, damping ratios) of a structure from measurements of the vibration response in operational condition.

What is PyOMA?

PyOMA is a python module that allows to perform OMA on ambient vibration measurments datasets.

PyOMA include the following algorithms:

Frequency Domain Decomposition (FDD)

1a. Original Frequency Domain Decomposition (FDD)

2a. Enhanced Frequency Domain Decomposition (EFDD)

3a. Frequency Spatial Domain Decomposition (FSDD)
Stochastic Subspace Identification (SSI)

2a. Covariance-driven Stochastic Subspace Identification (cov-SSI)

2b. Data-driven Stochastic Subspace Identification (dat-SSI)

To better untersdand the workflow of the functions, see the workflow here.

Installing PyOMA

As a prerequisite to install PyOMA, you need to install Anaconda first. You should install a Python version greather equal 3.5 or the software may run in troubles.

To fully install PyOMA, you need to run the following commands (in the following order):

pip install pandas
pip install scipy
pip install matplotlib
pip install seaborn
pip install mplcursors
pip install Py-OMA

To import PyOMA in your workspace, simply type:

import PyOMA

Dependencies

numpy (https://numpy.org/)
pandas (https://pandas.pydata.org/)
scipy -> signal (https://www.scipy.org/)
scipy.optimize -> curve_fit (https://www.scipy.org/)
scipy->linalg (https://www.scipy.org/)
matplotlib.pyplot (https://matplotlib.org/)
matplotlib.ticker -> [MultipleLocator,FormatStrFormatter] (https://matplotlib.org/)
matplotlib.patches (https://matplotlib.org/)
seaborn (https://seaborn.pydata.org/)
mplcursors (https://mplcursors.readthedocs.io/en/stable/)

Workflow

FDD:

1. run FDDsvp

	2.a run FDDmodEX to run original FDD
		
		and/or
		
	2.b run EFDDmodEX(method='EFDD') to run EFDD
		
		and/or
		
	2.c run EFDDmodEX(method='FSDD') to run FSDD

SSI

1.a run SSIcovStaDiag 
	
	2. run SSImodEX to run cov-SSI

		and/or

1.b run SSIdatStaDiag 
	
	2. run SSImodEX to run dat-SSI

Function Description

A complete description of the functions available in PyOMA can be found in the page Function Description.

Tudore / PyOMA