Labyrinthine metamaterials capable of absorbing sound waves: this is the new technology developed by six students at the Alta Scuola Politecnica, an international programme reserved for the best students from the Politecnico di Milano and the Politecnico di Torino.
It consists of panels capable of absorbing sound due to a particular internal structure featuring innovative acoustic properties. In fact, the performance of the panels is not only due to their constituent components, but also their labyrinthine geometric shape, which makes the sound wave reflect multiple times, attenuating it until it disappears. It is as if the sound is ‘lost’ in the labyrinth. These structures are capable of muffling different types of sound, from those with average frequencies typical of speech and some musical instruments, to those with low frequencies caused by engines. They may therefore be applied to a wide range of sectors, from construction to automobiles to domestic environments.
The six students who created the panel are Leonardo Bettini, Venus Hasanuzzaman Kamrul, Emanuele Musso, Fabio Nistri, Davide Piciucco, and Matteo Zemello. The panels are light and low cost, since they can be produced entirely with 3D printing using plastic waste.
The project was tested and validated in the Department of Energy-DENERG ‘Galileo Ferraris’ at the Politecnico di Torino with the industrial partner Phononic Vibes, a company created in 2018 as a spin-off of the Politecnico di Milano. The project will continue under the FET – Boheme European research path coordinated by the Università di Trento with the involvement of the Politecnico di Torino, Imperial College of London, and ETH Zürich.
