SHAPING PLASTIC METAMATERIALS
We exploit plasticity to shape and program mechanical metamaterials. We 3D printed architected hinged chains with an elasto-plastic material. By stretching the chain we store plastic deformation at the the hinges. The patterns are designed in such a way that each element accumulates plasticity individually. When releasing, the chain adopts any shape given by the curvature plastically encoded. We reverse engineer this mechanism in order to program any shape described by a 1D planar curve.
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FABRIC-BASED SOFT ROBOTICS
The coupling between elasticity and geometry in pressurized structures can lead to unexpected deformations. We focus in the design of a variety of soft mechanical actuators based on inflatable tubes made of a quasi-inextensible fabric. Upon inflation, the star at the left contracts radially, providing a soft grasping solution with tunable grabbing force.
COHESIVE STRENGTH OF BIRDNESTS
One striking difference between aggregates of flexible frictional fibers and other granular materials like rigid spheres is the effective cohesion of their assembly. We need to add glue or water capillary bridges between grains to shape aggregates of spherical particles and build sand castles. For fibers, no need for glue to build a nest. The goal is to characterize the macroscopic cohesive strength of the aggregate while changing the geometry of the fibers, the fibers mechanical properties and the packing preparation. At the right, you see an X-ray microtomography of a fiber assembly.
PHYSICS OF ORIGAMI
Folding elastic thin sheets can result in interesting behaviors. Foldable cones (f-cones), creases system meeting at a single vertex, exhibit two equilibrium shapes: a rest state and a snapped state. At the image you can see both states in a f-cone of 4 creases.
WRINKLING OF ELASTIC THIN SHEETS
A thin enough elastic sheet exhibits wrinkles when subjected to tensile stresses. We see this behavior all the time, in our clothes, bedsheets, fruits and in our own skin. However, wrinkling has important applications in the development of stretchable electronics, metrology devices and the treatment of scars. In this study we study the role of geometry in winkled patterns.
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INTERFACE DYNAMICS IN LIQUID CRYSTALS
Liquid crystals are fascinating materials. By exciting the liquid crystal with light and/or electro-magnetic fields we are able to control the orientation of the molecules and create interfaces in the liquid crystal that connects different orientational states. These interfaces exhibit rich spatiotemporal dynamics. Controlling the interface motion can help us to design new electro-optical devices (in the news!).