DYNAMIC MORPHING of ELASTIC PLATES VIA PRINCIPAL PARAMETRIC RESONANCE

Principal parametric resonances of elastic plates actuated by periodic in-plane stresses effected by embedded piezoelec-tric wires are investigated to describe the morphing scenarios of flexible, ultra-lightweight panels. A mechanical model of elastic plate including geometric nonlinearities and the parametric actuation provided by the piezoelectric wires, is adopted to for-mulate the nonlinear equation of motion. A bifurcation analysis is carried out by means of an asymptotic approach based on the method of multiple scales leading to a comprehensive paramet-ric study on the effect of the wires width on the morphing regions (i.e., parametric instability regions) associated with the princi-pal parametric resonances. The threshold voltages triggering the onset of the principal parametric resonances of the lowest three symmetric modes are also calculated as a function of the wires size so as to determine the voltage requirements for the morphing activation.