Fig. 1. Shape shifting of 3D curved morphologies from 2D kirigami sheets with different cut boundary curvatures subject to uniaxial tension.

a–c 2D precursors of three kirigami sheets patterned with parallel cuts but different boundary curvatures k_b highlighted in dashed white curves. circular (a), square (b), biconcave (c) samples with positive, zero, and negative boundary curvature, respectively. d–f The corresponding formed 3D curved shapes with different Gaussian curvature K. d Spheroidal shape with K > 0 at an applied strain of 0.30. e Cylindrical shape with K = 0 at an applied strain of 0.65. f Saddle shape with K < 0 at an applied strain of 1.47. Scale bars = 10 mm. g Force–displacement curves for the three 2D precursors. The shaded areas are the standard deviation between four different tests.