System Identification of Adaptive Gyroscopic Damper System Using Sensitivity Analysis

Abstract

System identification techniques with adaptive gyroscopic damper systems were proposed by applying the capability to change the moment of inertia around its gimbal axis, under a concept of self-identification with adaptive structure systems. The techniques to identify variations of modal parameters were proposed by sensitivity analyses of the natural frequency and the frequency response amplitude with respect to the modal parameters. Further technique to identify the modal parameters was proposed by extending the formulation with sensitivity of the frequency response amplitude with respect to the moment of inertia. To demonstrate the feasibility of each technique, numerical examples with cantilevered beam models were treated. The relations between the errors and non-dimensional system parameters, which include variations of modal parameters, the moment of inertia and the excitation frequency, were investigated numerically. The results indicated that the errors were sensitive to the relation of the system parameters and had singular points where the moment of inertia was close to optimum one to vibration suppression, and the excitation frequency was near the resonant frequency of the beam or the gimbal. The errors at the singular points were reduced by adjusting the moment of inertia or considering the excitation frequency.