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Cantilevers composed of glassy, photoresponsive liquid crystalline polymer networks (LCNs) are shown to oscillate at high frequency ( ∼ 50 Hz) and large amplitude when exposed to light from a 442 nm coherent wave (CW) laser. Added dimensionality to previously reported in-plane oscillations is enabled by adjusting the orientation of the nematic director to the long axis of the cantilever yielding in-plane bending accompanied by out-of-plane twisting (fl exural-torsional oscillation). The fundamental photoresponse of this class of glassy azobenzene liquid crystal polymer networks (azo-LCN) is further probed by examining the infl uence of cantilever aspect ratio, laser intensity, and temperature. The frequency of photodirected oscillations is strongly correlated to the length of the cantilever while the amplitude and threshold laser intensity for oscillation is strongly correlated to temperature.

This article presents a theoretical analysis for predicting the initial stiffness E*, and plastic collapse strength σ*pl of BCC micro-lattice blocks under compressive loading. This theoretical analysis is based on the observed deformation mechanisms, and can, in principle, be developed to predict the elastic properties of other micro-lattice structures. The analytical solutions are verified by comparing the predictions with FEM data using 1D beam and 3D solid elements and uniaxial compression tests on samples fabricated by selective laser melting. The FEM predictions using the 3D solid elements agree well with the experimental data for a wide range of strut aspect ratios, d/L. In addition, the range of applicability of the analytical model and the FEM predictions using beam elements are clarified.

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