Operational Modal Analysis

Do you need to do modal analysis without controlling the input?

ARTeMIS Modal

A powerful and versatile tool.
30 days trial.
Download

Next User Training Course

2-day Course, April 24-25, 2024, Aalborg, Denmark
Yes please – sign me up!

Operational Modal Analysis

You might wonder what Operational Modal Analysis, OMA, is and how it differs from the traditional Experimental Modal Analysis (EMA) that has been around for the past few decades. Operational Modal Analysis is also called output-only modal analysis, ambient response analysis, ambient modal analysis, in-operation modal analysis, and natural input modal analysis.

No matter the name, the idea is the same: Conduct a modal analysis without knowing and/or controlling the input excitation. This modal technology is capable of estimating the same modal parameters as the traditional known techniques. The modal parameters are the mode shape, the natural frequency and the damping ratio. Some thinks that Operational Modal Analysis just is another name for Operating Deflection Shapes, ODS. This is not the case. Operational Modal Analysis separates noise and inputs from the outputs and returns the unbiased modal information only.

  • Input Multiple Output Modal Technology.
    The Operational Modal Analysis are Multiple Input Multiple Output, MIMO, techniques. This means that the techniques are capable of estimating closely space modes and even repeated modes with a high degree of accuracy. Traditional modal anlysis techniques are typically Single Input Multiple Output, SIMO, or Multiple Input Single Output, MISO, or in rare cases even Single Input Single Output, SISO. Such testing procedures will not be able to find repeated poles due to the lack of mode separation.

  • Easier Laboratory Modal Testing.
    There is no need for vibration shaker or impact hammer anymore. If you are in your lab doing modal testing in a test rig on some structural component, just do some random tapping on the structure while you are measuring the vibration response in multiple locations. The tapping must be random in time but also spatially. The excitation produced in this way will be a good approximation of a multivariate white noise stochastic process.

  • Winning Technology in In-situ Modal Testing.
    The Operational Modal Analysis are Multiple Input Multiple Output, MIMO, techniques. This means that the techniques are capable of estimating closely space modes and even repeated modes with a high degree of accuracy. Traditional modal anlysis techniques are typically Single Input Multiple Output, SIMO, or Multiple Input Single Output, MISO, or in rare cases even Single Input Single Output, SISO. Such testing procedures will not be able to find repeated poles due to the lack of mode separation.

  • Modal Analysis in the Presence of Harmonic Excitation.
    The presence of rotating components “harmonics” in the data has for years been a nightmare to deal with. In many applications where rotating machinery is present in the structure being tested, it has been necessary to switch of the operation of the rotaing machinery while doing the modal analysis, or it has been necessary to rely on the use of Operating Deflection Shapes (ODS) analysis. However, ARTeMIS Modal is born with the ability to handle “harmonics” from rotating components, such as motors, pumps, propellers, wind turbines and generators.

Please have a look at the Technical Review for a technical introduction OMA and its similarities and differences to EMA.

Download OMA product data

Webinar Replay – See it or See it Again

Operational Modal Analysis using ARTeMIS Modal
September 2023

Additional Options

Distributors

We have officers around the world.
Find an office near you.
Find office

See our next coming webinar

Read more here

See also

ARTeMIS Modal

Check available versions and features.
Explore

Download

Download a 30-day trial of ARTeMIS Modal.
Go to download

Applications

Read more about the different analysis tools.
Explore

Cases

The use of ARTeMIS Modal in various customer case studies.
Explore

Webinar

Next available webinar courses.
Explore

Login

Request call
Please fill out the contact form below, and we’ll get back to you as quickly as possible.





    ARTeMIS Modal
    30 days trial
    Download