Systematic two-scale image analysis of extreme deformations in soft architectured sheets

The multi-scale nature of architectured materials raises the need for advanced experimental methods suitable identification their effective properties, especially when size is finite and they undergo extreme deformations. present work demonstrates that state-of-the art image processing combined with numerical analytical models provide a comprehensive quantitative description these solids global behaviour, including influence boundary conditions, manufacturing process, geometric constitutive non-linearities. To this end, an adapted digital correlation analysis used to track both elongations rotations particular features unit cell at local (homogenized) scale material. This permits observe unprecedented clarity strains various cells in structure detect deformation patterns heterogeneities homogenized strain distribution. method here demonstrated on elastic sheets undergoing longitudinal shear These results are compared non-linear element simulations, which also evaluate effects imperfections response. A skeletal representation solid then extracted from experiments create purely-kinematic truss-hinge model can accurately capture its behaviour. proposed be extended guide design two-dimensional featuring other regular, quasi-regular or graded patterns, subjected types loads.