An experimental investigation into the shock response of a compact wire rope isolator in its axial direction

Abstract

The use of wire rope isolators (WRIs) for vibration and shock response attenuation is extensive, as these isolators offer a high level of energy storage due to deflection in different directions, combined with high damping due to dry friction. As a result, they are marketed by manufacturers as excellent shock isolators. However, technical information regarding the shock response of these devices is limited, focusing on static properties and vibration isolation, whilst most of the scientific studies aim at the modelling and characterisation of properties. This study presents novel results from experiments involving both static and dynamic testing. Important information concerning the stiffness and damping characteristics are experimentally determined, as well as their behaviour under shock inputs of varying severity and duration for different payloads. It is shown that a WRI under low-level shock loads can be modelled crudely as a low dynamic stiffness system with a 5th order polynomial and nth power velocity damping. Although this approach is limited in predicting high input shocks and the dynamics of the hysteretic system under periodic loads compared to other models, it provides a simpler approach to predict the shock response of a WRI for engineering purposes.