Development of an active mass damper driven by an amplitude-modulated signal

Abstract

In recent mechanical systems, vibration problems have become obvious as the size and working speed of the equipment becomes smaller and faster. Much attention has been paid to develop vibration control devices, e.g., the vibration isolators and absorbers. The size of the absorbers is expected to be smaller in view of space saving and weight reduction. However, constitutive physical characteristics limit realization of the compact design without sacrificing the required damping performance. Specifically, it is difficult to attenuate low-frequency vibration by a miniaturized vibration control device. In the present study, we propose a novel active-type mass damper for vibration control of structures. By using a relatively small, a high frequency driven actuator to drive the mass with an amplitude-modulated control signal, the low frequency damping force can be demodulated. Mathematical formulation of the driving principle, both numerical and experimental verification of the low-frequency acceleration component to be used for the inertial control force are shown.