Dehydration- induced corrugated folding in Rhapis excelsa plant leaves

• 成果类型: Article
• 署名作者: Guo, Kexin; Liu, Mingchao; Vella, Dominic; Suresh, Subra; Hsia, K. Jimmy
• 署名单位: Nanyang Technological University; University of Birmingham; University of Oxford; Brown University; Massachusetts Institute of Technology (MIT); Nanyang Technological University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8629
• DOI: 10.1073/pnas.2320259121
• 发表日期: 2024-04-23
• 关键词: bulliform cells; actuation; water

摘要

Plant leaves, whose remarkable ability for morphogenesis results in a wide range of petal and leaf shapes in response to environmental cues, have inspired scientific studies as well as the development of engineering structures and devices. Although some typical shape changes in plants and the driving force for such shape evolution have been extensively studied, there remain many poorly understood mechanisms, characteristics, and principles associated with the vast array of shape formation of plant leaves in nature. Here, we present a comprehensive study that combines experiment, theory, and numerical simulations of one such topic-the mechanics and mechanisms of corrugated leaf folding induced by differential shrinking in Rhapis excelsa . Through systematic measurements of the dehydration process in sectioned leaves, we identify a linear correlation between change in the leaf - folding angle and water loss. Building on experimental findings, we develop a generalized model that provides a scaling relationship for water loss in sectioned leaves. Furthermore, our study reveals that corrugated folding induced by dehydration in R. excelsa leaves is achieved by the deformation of a structural architecture-the hinge cells. Utilizing such connections among structure, morphology, environmental stimuli, and mechanics, we fabricate several biomimetic machines, including a humidity sensor and morphing devices capable of folding in response to dehydration. The mechanisms of corrugated folding in R. excelsa identified in this work provide a general understanding of the interactions between plant leaves and water. The actuation mechanisms identified in this study also provide insights into the rational design of soft machines.