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The use of cellular elastomer substrates not only reduces its restriction on natural diffusion or convection of biofluids in the realm of stretchable electronics but also enhances the stretchability of the electronic systems. An analytical model of “zigzag” cellular substrates under finite deformation is established and validated in this paper. The deformed shape, nonlinear stress–strain curve, and Poisson’s ratio–strain curve of the cellular elastomer substrate calculated using the reported analytical model agree well with those from finite element analysis (FEA). Results show that lower restriction on the natural motion of human skin could be achieved by the proposed zigzag cellular substrates compared with the previously reported hexagonal cellular substrates, manifesting another leap toward mechanically “invisible” wearable, stretchable electronic systems.

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Three-dimensional (3D) serpentine mesostructures assembled by mechanics-guided, deterministic 3D assembly have potential applications in energy harvesting, mechanical sensing, and soft robotics. One limitation is that the serpentine structures are required to have sufficient bending stiffness such that they can overcome the adhesion with the underlying substrate to fully buckle into the 3D shape (global buckling). This note introduces the use of cellular substrate in place of conventional homogeneous substrate to reduce the adhesion energy and therefore ease the above limitation. A theoretical model based on energetic analysis suggests that cellular substrates significantly enlarge the design space of global buckling. Numerical examples show that the enlarged design space enables 3D serpentine structures with reduced maximum strains and resonant frequencies, which offers more possibilities for their potential applications.