Granular chains with fixed side decoration as impact protector and signals filter

We propose a granular architecture as a potential impact protector and signal filter. The system consists of monodispersed granular chains decorated with side beads fixed (welded) on sidewalls. Numerical results from usual monodispersed chains and simple tapered chains are employed as reference. An appropriate material combination and an optimal radii ratio between the side and axial granules show that more than 90% of the momentum amplitude of solitary pulses can be attenuated using a small and scalable system composed of five axial granules. Considering sinusoidal signals, the findings suggest that regular chains (monodispersed and tapered) are low-pass filters with cutoff frequencies as functions of the driven amplitude, restitutional losses, and tapering. The granular chain with fixed decoration filters all the input signals.