Leiden University Student Repository

Sabbadini, Alberico (2016)

Hierarchically folding mechanical metamaterials (of Rank III)

Master thesis | Physics (MSc)

In recent years, a number of artificial materials (so called metamaterials) have been developed, tailoring exotic responses to mechanical stress by exploiting geometrical features. A particular class of 2D metamaterials consists of tilings of polygons that can fold onto themselves by exploiting a mechanical instability triggered by compression. A subclass of these materials shows a sequence of two ordered states (one partially and one fully closed) when biaxially compressed; however, the reason why such networks fold in multiple steps is yet elusive and we are unaware of a general rule to design them; it is even unknown whether it is possible to increase the number of ordered states sequentially reached by a network during the folding process. In order to answer these questions, first we investigate a variety of designs to determine the role played by symmetries, topology and elastic energy; secondly, we focus on a hierarchical approach to design a network with three folding stages;...Show moreIn recent years, a number of artificial materials (so called metamaterials) have been developed, tailoring exotic responses to mechanical stress by exploiting geometrical features. A particular class of 2D metamaterials consists of tilings of polygons that can fold onto themselves by exploiting a mechanical instability triggered by compression. A subclass of these materials shows a sequence of two ordered states (one partially and one fully closed) when biaxially compressed; however, the reason why such networks fold in multiple steps is yet elusive and we are unaware of a general rule to design them; it is even unknown whether it is possible to increase the number of ordered states sequentially reached by a network during the folding process. In order to answer these questions, first we investigate a variety of designs to determine the role played by symmetries, topology and elastic energy; secondly, we focus on a hierarchical approach to design a network with three folding stages; finally, we fully characterize the mechanical response of this new network and we study how the order of the system evolves during the folding process.Show less

mechanical metamaterials hierarchical folding

Author

Sabbadini, Alberico

Faculty

Faculty of Science

Specialisation

Biological and Soft Matter Physics

Supervisors

Hecke, Martin van

ECTS Credits

5

Language

en