Damping of post-impact vibrations

Abstract

Impacts of solid bodies on rigid plates produce loud noise and strong vibrations. During this impact, flexural waves travel circularly outwards from the point of impact. These waves are used to determine the properties of the impacting body. For accurate location and momentum measurements, it is necessary that the set of flexural waves pass acceleration sensors just once without being disturbed by reflections. Different plate designs are tested with the aim to evaluate the shape, which offers the best damping properties against strong single impact. The investigations showed that the damping properties of the plates are significantly better with a star-shaped design, which is equipped with a damping layer. The novelty presented here is that the damping properties are significantly increased using a star-shaped plate with specially power law formed and damped edges. The work offers a solution to get significant better damping properties and a better signal for impact investigations. The results demonstrate that it is a promising approach for an impact detection system, which could be equally applicable to acoustic damping applications.