Octet lattice-based plate for elastic wave control

Motivated by the importance of lattice structures in multiple fields, we numerically investigate the propagation of flexural waves in a thin reticulated plate augmented with two classes of metastructures for wave mitigation and guiding, namely metabarriers and metalenses. The cellular architecture of this plate invokes the well-known octet topology, while the metadevices rely on novel customized octets either comprising spherical masses added to the midpoint of their struts or variable node thickness. We numerically determine the dispersion curves of a doubly-periodic array of octets, which produce a broad bandgap whose underlying physics is elucidated and leveraged as a design paradigm, allowing the construction of a metabarrier effective for inhibiting the transmission of waves. More sophisticated effects emerge upon parametric analyses of the added masses and node thickness, leading to graded designs that spatially filter waves through an enlarged bandgap via rainbow trapping. Additionally, Luneburg and Maxwell metalenses are realized using the spatial modulation of the tuning parameters and numerically tested. Wavefronts impinging on these structures are progressively curved within the inhomogeneous media and steered toward a focal point. Our results yield new perspectives for the use of octet-like lattices, paving the way for promising applications in vibration isolation and energy focusing

Emerging topics in nanophononics and elastic, acoustic, and mechanical metamaterials:An overview

This broad review summarizes recent advances and “hot” research topics in nanophononics and elastic, acoustic, and mechanical metamaterials based on results presented by the authors at the EUROMECH 610 Colloquium held on April 25–27, 2022 in Benicássim, Spain. The key goal of the colloquium was to highlight important developments in these areas, particularly new results that emerged during the last two years. This work thus presents a “snapshot” of the state-of-the-art of different nanophononics- and metamaterial-related topics rather than a historical view on these subjects, in contrast to a conventional review article. The introduction of basic definitions for each topic is followed by an outline of design strategies for the media under consideration, recently developed analysis and implementation techniques, and discussions of current challenges and promising applications. This review, while not comprehensive, will be helpful especially for early-career researchers, among others, as it offers a broad view of the current state-of-the-art and highlights some unique and flourishing research in the mentioned fields, providing insight into multiple exciting research directions

Emerging topics in nanophononics and elastic, acoustic, and mechanical metamaterials: an overview

This broad review summarizes recent advances and “hot” research topics in nanophononics and elastic, acoustic, and mechanical metamaterials based on results presented by the authors at the EUROMECH 610 Colloquium held on April 25–27, 2022 in Benicássim, Spain. The key goal of the colloquium was to highlight important developments in these areas, particularly new results that emerged during the last two years. This work thus presents a “snapshot” of the state-of-the-art of different nanophononics- and metamaterial-related topics rather than a historical view on these subjects, in contrast to a conventional review article. The introduction of basic definitions for each topic is followed by an outline of design strategies for the media under consideration, recently developed analysis and implementation techniques, and discussions of current challenges and promising applications. This review, while not comprehensive, will be helpful especially for early-career researchers, among others, as it offers a broad view of the current state-of-the-art and highlights some unique and flourishing research in the mentioned fields, providing insight into multiple exciting research directions

Emerging topics in nanophononics and elastic, acoustic, and mechanical metamaterials: an overview

This broad review summarizes recent advances and "hot"research topics in nanophononics and elastic, acoustic, and mechanical metamaterials based on results presented by the authors at the EUROMECH 610 Colloquium held on April 25-27, 2022 in Benicássim, Spain. The key goal of the colloquium was to highlight important developments in these areas, particularly new results that emerged during the last two years. This work thus presents a "snapshot"of the state-of-the-art of different nanophononics- and metamaterial-related topics rather than a historical view on these subjects, in contrast to a conventional review article. The introduction of basic definitions for each topic is followed by an outline of design strategies for the media under consideration, recently developed analysis and implementation techniques, and discussions of current challenges and promising applications. This review, while not comprehensive, will be helpful especially for early-career researchers, among others, as it offers a broad view of the current state-of-the-art and highlights some unique and flourishing research in the mentioned fields, providing insight into multiple exciting research directions

Elastic three-dimensional metaframe for selective wave filtering and polarization control

We experimentally achieve selective wave filtering and polarization control in a three-dimensional elastic frame embedding local resonators. By connecting multi-resonating elements to a frame structure, a complete low-frequency, subwavelength bandgap with strong selective filtering properties is obtained. Theory and experiments demonstrate the metaframe capability to selectively stop transverse waves while allowing longitudinal wave propagation as in "fluid-like"elasticity. This peculiar behavior, together with the complete bandgap structure, may open opportunities in the context of wave control, envisaging concurrent applications for three-dimensional filters and elastic wave polarizers

Parafiction as Matter and Method

The thesis examines the different ways in which artists have engaged with parafiction in the twentieth and twenty-first century. Parafiction – a fiction experienced as fact - has become an important mode of practice within contemporary art, with this shift concurrent to the exponential growth of digital technology. The term contemporary art is applied here in an expanded sense to acknowledge the effect of digital processes and matter on art and to include practices that use technology as form or subject or a combination of the two. Parafiction appears in various materialities, both digital and physical, and could be described as having neomateriality. Parafiction as Matter and Method inevitably locates the research within the context of the digital. The research investigates how the usage of parafiction has changed since 1989 with the rapid advancement of technology and widespread access to the internet. Changes in the social and political landscape have also affected the function of parafiction in contemporary society. These conditions are not necessarily time bound or linear. Drawing upon and extending Carrie Lambert-Beatty’s concept of parafictions (2009), the research is rooted in art history and contemporary art for its theoretical frameworks. The research engages deeply with art history and contemporary art in an expanded sense to contextualise and analyse parafictions, whilst utilising an interdisciplinary approach. To augment this deep context the research has combined the following fields: artistic practice, digital cultures, media studies, performance art, philosophy and politics. By synthesising this broad range of fields the research is original and complex in its approach aiming to consider the topic at a planetary scale within the bounds of the possible. As an overarching method, this research applies fiction as a method to produce new knowledge. The research uses primary and secondary methods including the production of a body of artwork and diagrammatic reasoning to augment the theoretical proposal. The art practice is employed as a method to synthesise the theory with practice and to apply the knowledge learnt outside of its text-based constraints. The practice appears as interludes interspersed throughout the thesis, that produce a duo-linear narrative with the aim of the thesis becoming an artwork in its own right. Primary data collection included interviews with relevant artists, attending and speaking at international conferences and research visits to exhibitions. This thesis has evolved through the attendance at international conferences as speaker and audience member, peer-reviewed publication, interaction with academic peers and research visits to exhibitions. This thesis evaluates how parafiction renegotiates physical and digital spatio-temporal parameters to offer alternatives for the present, pasts and futures, for both human and nonhuman users of those spaces. As parafiction becomes matter it has the ability to converge the digital and the physical to extend the lives of artworks beyond their initial existence. It is argued that fictioning methods have the most impact within contemporary art in its most expanded sense. The research advocates for parafiction as a vital method, found within artistic practice in the twentieth and twenty-first century, which produces new information and perspectives. This thesis uniquely concludes that parafiction is matter, as material that intersects and interacts with the modularity of digital technologies. Significantly, the research has found that parafiction acts as an additional module that connects physical and digital spatio-temporal with alternative potential for pasts, presents, and futures