Structural control for vibration reduction has important applications in many research areas, including the effect of earthquakes on buildings and aerodynamic forces on aircraft stability and performance. Both passive and active control techniques have been implemented, with the best solution usually involving a passive approach followed by an active one. This thesis presents an integrated modeling and controller design approach. Modal Cost Analysis (MCA) and Output Covariance Constraint (OCC) control are used to reduce a high-order aeroelastic wing model to establish the best controller for the reduced-order model, with a constraint on the covariance of the vibration outputs. MCA seeks to keep the modes that have the highest contribution to a given cost function. Using iterations on the two processes will allow a lower-order controller to be designed and result in the same performance.The OCC and MCA methods and their respective algorithms are presented, and an approach to integrate the two procedures is given. NASA's model used in this thesis is applied to the MCA and OCC algorithms using MATLAB. A 40th-order wing model is derived. The model reduction technique initially reduces the system to a 12th order one. A simulation of the OCC algorithm is performed on the reduced-order model and applied to the full-order model. The controller resulting in the best closed-loop performance is shown to significantly reduce the vibrations due to wind. A corresponding weighting matrix used in OCC is then used for a second round of MCA to further reduce the model to an 8th order model. A lower-order controller designed for this second model is shown to similarly reduce the output vibrations.
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