Planar kirigami metamaterials dramatically change their shape through a
coordinated motion of nearly rigid panels and flexible slits. Here, we study a
model system for mechanism-based planar kirigami featuring periodic patterns of
quadrilateral panels and rhombi slits, with the goal of predicting their
engineering scale response to a broad range of loads. We develop a generalized
continuum model based on the kirigami's effective (cell-averaged) deformation,
along with its slit actuation and gradients thereof. The model accounts for
three sources of elasticity: a strong preference for the effective fields to
match those of a local mechanism, inter-panel stresses arising from gradients
in slit actuation, and distributed hinge bending. We provide a finite element
formulation of this model and implement it using the commercial software
Abaqus. Simulations of the model agree with experiments across designs and
loading conditions.Comment: 15 pages, 8 figure