Flambage et vibrations non-linéaires d'une plaque stratifiée piézoélectrique. Application à un capteur de masse MEMS

Mots cles : Plaque stratifiee / non-linearites geometriques / flambage / vibrations / piezoelectrique Abstract - Buckling and non-linear vibrations of a piezoelectric stratified plate. Application to a MEMS mass sensor. This study proposes a model of a circular, non-symetrically laminated, piezoelectric plate, subjected to non-linear large amplitude vibrations. This model is built to simulate the behavior of a MEMS bio-sensor, designed to detect, automatically and autonomously, the presence of a given molecule in an aqueous solution. Because of both the laminated structure and the fabrication process, prestresses are observed, with different signs and intensities from one layer to another. This is responsible of a non-planar deformed geometry of the plate at rest. Moreover, experimental results show that a geometrically non-linear response is observed, with curved freqeuncy responses. A continuous non- linear model of the von-Karman type is used and discretized by an expansion of the solution onto the mode shape basis of the plate without prestresses. It's response is numerically computed by a continuation method, in order to predict the system's non-linear behavior.