Flutter analysis by using H-infinity-norm

Flutter is a typical dynamic instability phenomenon in aeroelastic systems. It is very important to determine the critical flutter point in aeroelastic analysis. Based on the H-inflnity control theory, we consider an aeroelastic system a multiple-input and multiple-output (MIMO) system, and derive its transfer function matrix. The H-infinity-norm of this transfer matrix will approach to infinity near the critical flutter point. Using this unique property of the H-infinity-norm, we develop a detailed algorithm to automatically search for the flutter point in frequency domain with less complexity than the traditional method. It is demonstrated that the results of the present method are in agreement with those of classical method.