330-0535/01 – Experimental Modal Analysis (EMA)
| Gurantor department | Department of Applied Mechanics | Credits | 4 |
| Subject guarantor | doc. Ing. Michal Šofer, Ph.D. | Subject version guarantor | doc. Ing. Michal Šofer, Ph.D. |
| Study level | undergraduate or graduate | Requirement | Compulsory |
| Year | 1 | Semester | winter |
| | Study language | Czech |
| Year of introduction | 2020/2021 | Year of cancellation | |
| Intended for the faculties | FS | Intended for study types | Follow-up Master |
Subject aims expressed by acquired skills and competences
Students will master problematics of modal tests both theoretically and practically. They will be able recognize in their future engineering practise, when it is appropriate to utilize results obtained by modal test as a part of solving the current problem and they will be able to gain these results. They will be able to use data from experiment for finite element models updating, which significantly increases validity of computational methods.
Teaching methods
Lectures
Tutorials
Experimental work in labs
Summary
The module deals with the identification of dynamical properties of mechanical structures using experimental modal analysis method. Student will become acquaintant with instrumentation and software used in modal testing, with preparation of a modal test, with methods of frequency response functions measurement and with methods of extracting modal parameters from the measured data. They will also learn, how to use the experimentally derived modal parameters for computational models updating.
Compulsory literature:
[1] BILOŠOVÁ, A.: Modal Testing. Dostupný z https://edison.sso.vsb.cz/cz.vsb.edison.edu.study.prepare.web/StudySupportsFileServlet/741add29-8922-4f2c-9ce4-563c2f19dc18;1.1/EMA_skriptaEN.pdf?inline=true
[2] EWINS, D.J.: Modal Testing: Theory, Practice and Application, second edition, Research Studies Press, Ltd., England 2000
Recommended literature:
Way of continuous check of knowledge in the course of semester
Student will prove his/her knowledge by independently operating measurement equipment and software for modal analysis and by his/her ability to perform modal test of a machine part by him/herself. The course ends with a combined exam.
E-learning
Other requirements
Knowledge of Technical Vibrations, Dynamics I and Vibration Diagnostics.
Prerequisities
Subject has no prerequisities.
Co-requisities
Subject has no co-requisities.
Subject syllabus:
1. Modal test, its purpose and way of performing, basic concepts.
2. Dual channel analysis, definition of basic functions, coherence function.
3. Mobility measurement methods, basic measurement set-up.
4. Analyzers, digital signal processing.
5. Excitation methods.
6. Introduction to experimental modal analysis theory. One degree-of-freedom system, description and properties of 1 DOF frequency response function.
7. Undamped multi degree-of-freedom system, orthogonal properties and modal shapes scaling.
8. Damped multi degree-of-freedom system, types of damping.
9. Methods of extracting modal parameters.
10. Creating mathematical models of a structure (response, modal and spatial models).
11. Methods of comparing theoretical (FEM) model and experimentally derived model, modal assurance criterion, mass and stiffness error matrices.
12. Structural modifications.
13. Operational deflection shapes. Application of experimental modal analysis in technical diagnostics.
14. Operational modal analysis, multiple-input multiple-output analysis.
Conditions for subject completion
Occurrence in study plans
Occurrence in special blocks
Assessment of instruction