Fig. 4: Zero-thickness origami-kirigami regular tetrahedrons and thick-panel regular tetrahedral structures (TPRTSs).

A, B Zero-thickness 2D and 3D origami-kirigami patterns of regular tetrahedrons, respectively; the blue solid lines represent mountain creases, the red dashed lines represent valley creases, and the green dotted line represents slit creases. C, D The 3D models of TPRTSā1 and TPRTS-2, respectively; E Rates of change in volume and surface area of TPRTSs. F, G The folding sequences of TPRTS-1 and TPRTS-2, respectively. H The folding sequence of a metal prototype of TPRTS-2.