In arthropods, evolution has created a remarkably sophisticated class of imaging systems, with a wide-angle field of view, low aberrations, high acuity to motion and an infinite depth of field. A challenge in building digital cameras with the hemispherical, compound apposition layouts of arthropod eyes is that essential design requirements cannot be met with existing planar sensor technologies or conventional optics. Here we present materials, mechanics and integration schemes that afford scalable pathways to working, arthropod-inspired cameras with nearly full hemispherical shapes (about 160 degrees). Their surfaces are densely populated by imaging elements (artificial ommatidia), which are comparable in number (180) to those of the eyes of fire ants (Solenopsis fugax) and bark beetles (Hylastes nigrinus). The devices combine elastomeric compound optical elements with deformable arrays of thin silicon photodetectors into integrated sheets that can be elastically transformed from the planar geometries in which they are fabricated to hemispherical shapes for integration into apposition cameras. Our imaging results and quantitative ray-tracing-based simulations illustrate key features of operation. These general strategies seem to be applicable to other compound eye devices, such as those inspired by moths and lacewings (refracting superposition eyes), lobster and shrimp (reflecting superposition eyes), and houseflies (neural superposition eyes).

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Classical molecular dynamics is applied to study the energy dissipation (the Q factor) of the cantilever-type beam oscillators of single wall and double-walled carbon nanotubes (CNTs). The study finds that the Q factor of the CNT beam oscillator varies with the temperature T following the 1/T(0.36) dependence. For single wall CNT, the Q factor drops from 2 x 10(5) at 0.05 K to 1.5 x 10(3) at 293 K. The study further reveals that the weak interlayer binding strength and the interlayer commensurance significantly increases the energy dissipation in the double-walled CNT oscillator.

Combining compliant electrode arrays in open-mesh constructs with hydrogels yields a class of soft actuator, capable of complex, programmable changes in shape. The results include materials strategies, integration approaches, and mechanical/thermal analysis of heater meshes embedded in thermoresponsive poly(N-isopropylacrylamide) (pNIPAM) hydrogels with forms ranging from 2D sheets to 3D hemispherical shells.