Manipulating waves with LEGO$^{\circledR}$ bricks: A versatile experimental platform for metamaterial architectures

TL;DR

This paper presents a reconfigurable experimental platform using LEGO bricks and laser vibrometry to study wave phenomena in metamaterials, enabling rapid testing of various topologies and illustrating key wave manipulation effects.

Contribution

It introduces a versatile, easily reconfigurable LEGO-based platform for phononic metamaterials research, facilitating rapid proof-of-concept experiments and educational demonstrations.

Findings

Demonstrated waveguiding and seismic isolation effects.

Visualized differences between Bragg-based and locally resonant bandgaps.

Showcased platform's rapid reconfigurability for diverse topologies.

Abstract

In this letter, we discuss a versatile, fully-reconfigurable experimental platform for the investigation of phononic phenomena in metamaterial architectures. The approach revolves around the use of 3D laser vibrometry to reconstruct global and local wavefield features in specimens obtained through simple arrangements of LEGO$^{\circledR}$ bricks on a thin baseplate. The agility by which it is possible to reconfigure the brick patterns into a nearly endless spectrum of topologies makes this an effective approach for rapid experimental proof of concept, as well as a powerful didactic tool, in the arena of phononic crystals and metamaterials engineering. We use our platform to provide a compelling visual illustration of important spatial wave manipulation effects (waveguiding and seismic isolation), and to elucidate fundamental dichotomies between Bragg-based and locally resonant bandgap mechanisms.