Facile strain analysis of largely bending films by a surface-labelled grating method

Abstract

Mechanical properties of flexible films, for example surface strain of largely bending films, are key to design of stretchable electronic devices, wearable biointegrated devices, and soft microactuators/robots. However, existing methods are mainly based on strain-gauge measurements that require miniaturized array sensors, lead wires, and complicated calibrations. Here we introduce a facile method, based on surface-labelled gratings, for two-dimensional evaluation of surface strains in largely bending films. With this technique, we demonstrate that soft-matter mechanics can be distinct from the mechanics of hard materials. In particular, liquid-crystalline elastomers may undergo unconventional bending in three dimensions, in which both the inner and outer surfaces of the bending film are compressed. We also show that this method can be applied to amorphous elastomeric films, which highlights the general importance of this new mechanical evaluation tool in designing soft-matter-based electronic/photonic as well as biointegrated materials.

Shape‐Shifting Azo Dye Polymers: Towards Sunlight‐Driven Molecular Devices

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Vectorial strain gauge method using single flexible orthogonal polydimethylsiloxane gratings

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Flexible Multifunctional Sensors for Wearable and Robotic Applications

“…[177][178][179] In contrast to the advanced photonic crystals, they used the simplest type of classical photonic crystals as the diffraction grating to diffract incident light. [177][178][179] In contrast to the advanced photonic crystals, they used the simplest type of classical photonic crystals as the diffraction grating to diffract incident light.…”