Summary
Modal Analysis has become a well known tool to derive the mode shapes of existing machine structures. In this paper, it will be shown that modal parameters derived from modal testing can be used to investigate the effect of potential design changes on a test structure.
The method described here uses the fact that transfer functions given by the modal parameters can be written as rational functions. Considering a desired modification we can build the rational transfer functions of the modified structure. Then, the modal parameters are calculated again by partial fraction expansion, that means without processing the frequency responses numerically. The method is realized for mass, stiffness and damping modifications. It can be extended to coupling of substructures. Furthermore, an example of a mass modification of an existing structure is presented in the paper.
This is a preview of subscription content, log in via an institution to check access.
Preview
Unable to display preview. Download preview PDF.
References
RICHARDSON M. — Modal Analysis using Digital Test Systems, Shock and Vibration Information Center, Washington, May 1975
RICHARDSON M., KNISKERN J. — Identifying Modes of Large Structures from Multiple Input and Response Measurements. Society of Automotive Engineers SAE 760875, 1976
VAN LOON P. — Modal Parameters of Mechanical Structures, Ph.D. dissertation K.U. Leuven, Belgium, 1974
GYGAX P.E. — Possibilities and Limits of Modal Analysis (in French), Mécanique No. 341/342, May/June 1978
PETERS J., MERGEAY M. — Dynamic Analysis of Machine Tools using Complex Modal Method. Annals of CIRP, Vol. 25/1, 1976
WECK M., TEIPEL K. — Dynamisches Verhalten spannender Werkzeugmaschinen, Springer 1977
FINKE R. — Berechnung des dynamischen Verhaltens von Werkzeugmaschinen. Diss. TH Aachen, 1977
SNOEYS R., ROESEMS D., VAN DEURZEN U., VANHONACKER P. — Survey of Modal Analysis Applications. Annals of CIRP, Vol.28/2, 1979
BROWN D. — Grinding Dynamics. Ph.D. dissertation, University of Cincinnati, 1976
LINCOLN A.P. — Modelling of Structural Behaviour from Frequency Response Data. Institute of Sound and Vibration Research, Southampton, Techn. Rept. No. 83, Sep. 1977
RAMSEY K. — Effective Measurements for Structural Dynamics Testing. Sound and Vibration, Part I, Nov. 1975, Part II, April 1976
JENKINS M.A. — Zeros of a Real Polynomial. ACM Transactions on Mathematical Software, Vol. 1, No. 2, June 1975.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Copyright information
© 1981 The Department of Mechanical Engineering, University College of Swansea
About this chapter
Cite this chapter
Looser, W. (1981). Modelling of Mechanical Structures Based on Modal Parameters. In: Alexander, J.M. (eds) Proceedings of the Twenty-First International Machine Tool Design and Research Conference. Palgrave, London. https://doi.org/10.1007/978-1-349-05861-7_62
Download citation
DOI: https://doi.org/10.1007/978-1-349-05861-7_62
Publisher Name: Palgrave, London
Print ISBN: 978-1-349-05863-1
Online ISBN: 978-1-349-05861-7
eBook Packages: EngineeringEngineering (R0)