Multiscale tunability of solitary wave dynamics in tensegrity metamaterials

TL;DR

This paper introduces a new class of tensegrity-based nonlinear metamaterials that can be tuned to exhibit elastic hardening or softening, enabling novel impact mitigation through solitary wave manipulation without energy dissipation.

Contribution

It presents the design and analysis of tunable tensegrity metamaterials capable of transforming impact waves into solitary waves with unique behaviors at interfaces.

Findings

Softening regime transforms compression pulses into rarefaction waves.

Interfaces cause anomalous reflection and transmission of solitary waves.

Metamaterials can mitigate impacts without energy dissipation.

Abstract

A new class of strongly nonlinear metamaterials based on tensegrity concepts is proposed and the solitary wave dynamics under impact loading is investigated. Such systems can be tuned into elastic hardening or elastic softening regimes by adjusting local and global prestress. In the softening regime these metamaterials are able to transform initially compression pulse into a solitary rarefaction wave followed by oscillatory tail with progressively decreasing amplitude. Interaction of a compression solitary pulse with an interface between elastically hardening and softening materials having correspondingly low-high acoustic impedances demonstrates anomalous behavior: a train of reflected compression solitary waves in the low impedance material; and a transmitted solitary rarefaction wave with oscillatory tail in high impedance material. The interaction of a rarefaction solitary wave with an interface between elastically softening and elastically hardening materials with high-low impedances also demonstrates anomalous behavior: a reflected solitary rarefaction wave with oscillatory tail in the high impedance branch; and a delayed train of transmitted compression solitary pulses in the low impedance branch. These anomalous impact transformation properties may allow for the design of ultimate impact mitigation devices without relying on energy dissipation.