Vibration control of adaptive aircraft wings modeled as tapered thin-walled beams

A study of the vibrational control of adaptive doubly-tapered cantilevered beams, simulating an aircraft wing, exposed to time-dependent externam pulses is presented. Whereas the beam structure encompasses non-classical properties such as transverse shear, anisotropy and heterogeneity of their constitutent materials, the active control capabilities are based upon the implementation of the adaptive materials technology. Herein, the adaptive feature is achieved through the converse piezoelectric effect that consists of the generation of localized strains in response to an applied voltage. Piezoactuators in the form of patches or spread allover the beam span are considered. The active control involves the dynamic response to arbitrary time-dependent external pulses. The closed-loop dynamic response time histories are obtained via the use of the piezoelectrically induced boundary moment control, and through the implementation of a modified bang-bang control strategy that involves a maximum value constraint imposed on the input voltage. Numerical simulations emphasing the performance of the adopted control strategies intended to contain and even reduce to zero the response quantities when time unfolds are presented, and pertinent conclusions are outlined.