<title>Dynamic modeling and neural control of composite shells using piezoelectric devices</title>

Abstract

A modal dynamic model is developed for the active vibration control of laminated doubly curved shells with piezoelectric sensors and actuators. The dynamic effects of the mass and stiffness of the piezoelectric patches are considered in the model. Finite element equations of motion are developed based on shear deformation theory and implemented for an isoparametric shell element. The mode superposition method is used to transform the coupled finite element equations into a set of uncoupled equations in the modal coordinates. A robust controller is developed using Linear Quadratic Gaussian with Loop Transform Recovery (LQG/LTR) design methodology to calculate the gain and actuator voltage requirements. A neural network controller is then designed and trained offline to emulate the performance of the LQG/LTR controller. Numerical results are presented for a spherical shell showing the variation in initial conditions and structural parameters. The neural network controller is shown to effectively emulate the LQG/LTR controller with slightly improved performance over that of the LQG/LTR controller for some cases.