Optimal vibration control of smart composite beams with optimal size and location of piezoelectric sensing and actuation

Control performances of smart structures depend on the size and location of the piezoelectric actuators and sensors as well as on the applied control algorithm. This article presents optimal vibration control of a thin-walled composite beam by using the fuzzy optimization strategy based on the particle swarm optimization algorithm. The optimization of the size and location of the conventionally collocated piezoelectric actuators and sensors, and optimization of the controller parameters are performed separately. The optimization criteria for optimal size and location of piezoelectric actuators and sensors are based on eigenvalues of the controllability Grammian matrix. The optimization procedure implies constraint of the original dynamic properties change and limitation of the beam mass increase. The particle swarm optimization-based linear quadratic regulator has been implemented for optimal vibration control in order to maximize the modal closed-loop damping ratios and minimize the control voltages required for actuation while keeping them below breakdown voltage for the used piezoelectric actuator. A pseudo-goal function, derived from the fuzzy set theory, gives an expression for global objective functions eliminating the use of weighting coefficients and penalty functions. The problem is formulated using the finite element method based on the third-order shear deformation theory. Several numerical examples are presented for the cantilever beam.