| Izvleček: | <p>This dissertation proposed a kinematic-based construction method for reconfigurable mechanical metamaterials. This was achieved by entrenching kinematic mechanisms with predefined motion paths within the unit cells of the metamaterial and connecting the units according to carefully chosen topology pattern. The developed metamaterials are able to perform complex transformation between different configurations, which brings superior tuneable physical properties. The major findings of this dissertation are in following four areas.</p>
<p>First, this research built a bridge between mechanism networks and mechanical metamaterials. The theories of planar and spatial mechanisms were utilised to analyse and program the behaviour of metamaterials. Various interesting metamaterials were developed, including materials whose expansion ratio, volumetric strain and porosity are programmable; structures with multiple deformation paths due to their built-in kinematic bifurcation; and metamaterials with constant negative Poisson’s ratios that can be programmed by the parameters of the building blocks. The kinematic-induced design strategy paves the way for a new class of metamaterials that can perform reliable large deformation along predefined motion paths.</p>
<p>Second, different strategies to construct three dimensional (3D) kinematic metamaterials were investigated. While most current origami metamaterials focus on thin shell planar structures, this thesis endeavoured to explore 3D materials. A tilting unit method was proposed for single layer 3D metamaterial, whereas a spatial mechanism-entrenched design strategy was developed for more general 3D metamaterials. The topology and transformation of the unit cells were obtained using the kinematic analysis so that the tuneability of the material became a built-in feature of these metamaterials.</p>
<p>Third, an application of kinematic metamaterials as frequency selective surfaces has been investigated. The metamaterials were designed to have multi-stable states so that it can be locked mechanically in various configurations corresponding to specific passband. The metamaterials were fabricated and tested in electromagnetics experiments to validate their functionality.</p>
<p>Finally, the fabrication strategies of various kinematic metamaterials were explored. Laser engraving technique was mainly used for planar metamaterials. For 3D metamaterials, a multi-material 3D printing method was investigated for millimetre-scale samples, and a multi-process lamination method was developed for meso-scale paper prototypes. These methods provided rich and useful experience for the development of functional metamaterials in the future.</p>
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