Shaping with plasticity

Changes of in-plane dimensions lead to out-of-plane buckling and to non-zero Gaussian curvature of architected membranes. In this work, we fix a programmed buckled shape with the precise control of irreversible plastic deformations. A periodic membrane is deformed with simple uniaxial stretching. The periodic element is a cell parametrized to produce local changes of metric. The global change of properties results from the mechanical behavior of the cell assembly. We present a two-level validating approach. We validate our analytical and numerical models with a complete experimental characterization of periodic cells’ mechanics using 3d printed lattices. At the level of the assembly we show experimentally that precise curvatures can be realized at large scale to form structure that are structurally rigid. We create a new paradigm for programmable surfaces: they can both be mechanically functional and created using a simple actuation method.