Title :
3F-4 Experimental Evidence and Modeling of Microsliding on Cantilever Quartz Beam
Author :
Nouira, H. ; Foltete, E. ; Hirsinger, L. ; Ballandras, S.
Author_Institution :
Inst. FEMTO-ST, Besancon
Abstract :
The design of mechanical systems requires various studies in order to ensure an optimal behavior during operation. In particular, the study of its dynamic behavior makes it possible to evaluate the role of a connection in the energy dissipation mechanisms. In this context, an experimental setup dedicated to small structures has been developed to quantify damping due to microsliding at the beam-clamp interface. The mechanical characterization of the clamped connection is carried out by experimental dynamic tests on a free-clamped structure. The instantaneous frequencies and damping are identified by the wavelet transform technique of a slightly non-linear system. In parallel, numerical prediction of the equivalent damping is achieved thanks to the implementation of the regularized Coulomb law in a finite element model. A genetic algorithm and artificial neural networks are used to update the stiffness parameter and the friction coefficient. The optimized model is in good agreement with experimental results. It allows for determining the spatial distribution of microsliding and tangential force along the contact interface. The dissipated energy and equivalent damping are finally deduced according to the dynamic deflection of the free part of the beam.
Keywords :
beams (structures); cantilevers; damping; elasticity; finite element analysis; genetic algorithms; mechanical contact; mechanical engineering computing; micromechanical devices; neural nets; quartz; sliding friction; supports; vibrations; wavelet transforms; Coulomb law; artificial neural networks; beam-clamp interface; cantilever quartz beam; clamped connection; contact interface; dynamic behavior; dynamic tests; energy dissipation mechanisms; equivalent damping; finite element model; free-clamped structure; friction coefficient; genetic algorithm; mechanical characterization; mechanical systems design; microsliding modeling; nonlinear system; spatial tangential force distribution; stiffness parameter; wavelet transform technique; Damping; Energy dissipation; Finite element methods; Frequency; Mechanical systems; Nonlinear dynamical systems; Predictive models; Structural beams; Testing; Wavelet transforms;
Conference_Titel :
Ultrasonics Symposium, 2007. IEEE
Conference_Location :
New York, NY
Print_ISBN :
978-1-4244-1384-3
Electronic_ISBN :
1051-0117
DOI :
10.1109/ULTSYM.2007.60