H∞ Control for Flutter Suppression of a Laminated Plate with Self-Sensing Actuators

Active flutter suppression system of a composite plate wing model is designed using a reduced order model. The analysis for a laminated composite wing with segmented piezoelectric sensor/actuator pairs is conducted by the Ritz solution technique. Unsteady aerodynamic forces calculated by doublet lattice method are approximated as the transfer functions of the Laplace variable by the minimum state method. Among the aerodynamic states obtained from rational function approximation, only one aerodynamic state is included in the plant model for feedback purpose. The neglected aerodynamic states are regarded as modeling error. The control system uses the integrated and collocated piezoelectric self-sensing actuator pairs so as to prohibit the non-minimum phase model and the spillover due to the unmodeled dynamics. Based on the mixed-sensitivityH∞ control method, the control parameters are determined. Using a simple wing model, the performance of the controlled system is shown in the frequency and time domain respectively. The electric current and the power requirement for aeroelastic control are also predicted.