The Adaptive Power of <i>Ammophila arenaria</i>: Biomimetic Study, Systematic Observation, Parametric Design and Experimental Tests with Bimetal

• Main Authors: Tarciana Araújo Brito de Andrade, José Nuno Dinis Cabral Beirão, Amilton José Vieira de Arruda, Cristina Cruz
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Polymers
• Subjects: biomimetic and design; climate adaptation; <i>Ammophila arenaria</i>; reversible leaf movement; bimetal
• Online Access: https://www.mdpi.com/2073-4360/13/15/2554

The aim of our study was to apply a biomimetic approach, inspired by the <i>Ammophila arenaria</i>. This organism possesses a reversible leaf opening and closing mechanism that responds to water and salt stress (hydronastic movement). We adopted a problem-based biomimetic methodology in three stages: (i) two observation studies; (ii) how to abstract and develop a parametric model to simulate the leaf movement; and (iii) experiments with bimetal, a smart material that curls up when heated. We added creases to the bimetal active layer in analogy to the position of bulliform cells. These cells determine the leaf-closing pattern. The experiments demonstrated that creases influence and can change the direction of the bimetal natural movement. Thus, it is possible to replicate the <i>Ammophila arenaria</i> leaf-rolling mechanism in response to temperature variation and solar radiation in the bimetal. In future works, we will be able to propose responsive facade solutions based on these results.