Cable Vibration Suppression with Inerter-Based Absorbers

Stay cables are prone to vibrations due to their low inherent damping. This paper presents an approach for systematic identification of beneficial passive vibration absorber layouts consisting of a damper, a spring, or an inerter. With the proposed method, optimal configurations among all layouts with three elements or fewer are identified. The inerter is a two-port mechanical element with the property that the applied force is proportional to the relative acceleration between its terminals. In this work, a finite-element taut cable model, with a generic vibration absorber represented by its admittance function, is first established. Two performance measures, depending on the length of the cable and the forcing conditions, are introduced to assess the effect of candidate absorbers. Potential advantages of low-complexity inerter-based absorber layouts are then systematically investigated, with corresponding element values in these layouts identified. Building on this, the effect of series compliance is also examined for beneficial absorber layouts. It is shown that, up to a certain inertance, which depends on the stiffness of the series compliance, the performance advantages over a viscous damper can be maintained, or even increased in some cases, if the element values are properly tuned.