engleski

Synthesis of the inerter by direct acceleration feedback

Physical realisations of the inerter are often such that they must be either large scale, i.e. rack and pinion inerters, or they inherently include additional elements in parallel or in series with the inerter, i.e. shunted electromechanical transducers or active force feedback inerter realisations, or alternatively they bring along a large parasitic damping, i.e. fluid-based inerters. In this study inerter is realised by feeding back the subtracted outputs of two accelerometers attached to a reactive force actuator terminals. Although in theory such feedback loop is unconditionally stable due to the collocated sensor-actuator arrangement, in practice it may not exhibit good stability properties due to the lack of duality between the sensors and the actuator in conjunction with the internal dynamics of the transducers. Therefore in this paper dynamics of seismic accelerometer sensors and an electrodynamic actuator are fully incorporated into a theoretical model of such an inerter. The inerter model is coupled to a two degree of freedom mechanical system in order to study the stability of the feedback loop and the maximum possible synthesisable inertance. The results indicate that it is crucial to have a highly damped accelerometer resonance in order to achieve good stability and large synthesised inertance.

Interter, Active vibration control, Vibration isolation

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