Application of a virtual inerter in active vibration control using inertial actuators

In this paper the application of an inerter to a control system based on inertial actuators is investigated. Since the dynamics of this kind of actuators affects the stability of the controlled system, the application of the inerter aims to limit instability problems by shifting down the resonance frequency of the actuator. The interaction of this passive element with the other vibration modes of the structure under control is not negligible. The inerter should be physically placed in parallel with the elastic suspension of the actuator and the transducer; in this paper, the inerter behavior is simulated by the inertial actuator through an acceleration feedback. First, the study is carried out on a two degrees-of-freedom model and stability considerations are made; then, the approach is implemented on the Finite Element model of a clamped-clamped beam which is also used as experimental test rig. Finally, the proposed solution is validated with experimental results.