Optimization of Locations and Fiber Orientations of Piezocomposite Actuators on Flexible Wings for Aeroelastic Control

Abstract

Smart piezoelectric fiber composite materials have the potential to improve the aerodynamic properties and aeroelastic responses of flexible wings. Aeroelastic control performance significantly depends on the configurations of such anisotropic actuators. In this paper, configuration optimization of piezocomposite actuators, including locations and lead zirconate titanate (PZT) fiber orientations, is investigated to enhance the aeroelastic control authority of flexible wings within a flight envelop. The effect of fiber orientation on the anisotropic actuation characteristics of the piezocomposite actuator is analyzed. A mathematical model of the piezocomposite-actuated flexible wings is established with the integration of the finite element model, actuation forces, and Theodorsen unsteady aerodynamic loads. An optimization approach is developed based on a controllability Gramian matrix and solved using a genetic algorithm (GA). The effects of fluid-structure interaction and flight speed on the optimal configurations of piezocomposite actuators are investigated and discussed. The results imply that both the best location and the PZT fiber orientation of the piezocomposite actuator are affected by fluid-structure interaction. The torsional modes receive greater controllability in aeroelastic control than the pure structural vibration control of flexible wings, and the optimal fiber orientations increase with flight speed.