We report on the fabrication and electro-mechanical characterization of a nanocomposite system exhibiting anisotropic electrical response under the application of tactile compressive stresses (5 kPa) at low frequencies (0.1–1 Hz). The nanocomposite is based on a chemically cross-linked gel incorporating a highly conductive ionic liquid and surface functionalized barium titanate (BaTiO3) ferroelectric nanoparticles. The system was engineered to respond to mechanical stimulations by combining piezoionic and piezoelectric activity, generating electric charge due to a redistribution of the mobile ions across the polymer matrix and to the presence of the electrically polarized ceramic nanoparticles, respectively. The nanocomposite response was characterized in a quasi-static regime using a custom-designed apparatus. The results obtained showed that the combination of both piezo-effects led to output voltages up to 8 mV and anisotropy in the response. This allows to discriminate the sample orientation with respect to the load direction by monitoring the phase and amplitude modulation of the output signal. The integration of cluster-assembled gold electrodes produced by Supersonic Cluster Beam Deposition (SCBD) was also performed, enabling to enhance the charge transduction efficiency by a factor of 10, compared to the bare nanocomposite. This smart piezoionic/piezoelectric nanocomposite represents an interesting solution for the development of soft devices for discriminative touch sensing and objects localization in physically unstructured environments.

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The merging of electronically conductive elements with soft polymeric materials gave birth to the novel field of soft and stretchable electronics and robotics, where the key aspect is the maintenance of the electrical properties even under severe mechanical deformation. Here we review the variety of fabrication techniques that have been designed, studied and tested, leading to foresee how soft technologies can have a revolutionary impact in the progress of biomedicine and pre-clinical practice, wearable electronics, environmental monitoring and recognition, smart farming and precision agriculture, energy harvesting and storage. A particular focus is given to wet and dry techniques for 2D and 3D printed electronics that allow the coupling of compliant conductive elements on complex three-dimensional objects and platforms. We discuss how a selection and a targeted optimization amongst different nanoscale building blocks nanomaterials and deposition techniques are now necessary. The watchwords to be prioritized are scalability, versatility, environmental sustainability and biocompatibility, integration and reduction of the fabrication steps. The target is the design of an eco-friendly and versatile approach for the full additive manufacturing of free-form advanced soft electronic devices, eventually biocompatible and biodegradable, with a multi-layer and multi-material process able to print both active and passive 3D elements on soft polymeric platforms. The sequential combination of dry and wet spray printing shows to be one of the most promising approach.

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In 1960, cinema critic Jonas Mekas welcomed the advent of the New American Cinema, praising the wave of independent movies produced in late 1950s for their casual and fragmentary nature. The key feature of these productions, which was particularly remarkable in the case of two major features—Shadowsby John Cassavetes andPull My Daisyby Alfred Leslie and Robert Frank—was an anti-Hollywood style that relied on improvisatory practices affecting all structural levels: from the acting to the montage, from the photography to the soundtrack. The style of this “spontaneous cinema” was a pastiche of multiple improvisatory practices, borrowed from bebop, beat poetry, and Stanislavsky’s acting techniques, which defied traditional cinematographic narratives. A close analysis ofShadowsandPull My Daisyreveals the multiple forms of improvisation that shaped these movies’ “spontaneous poetics” and the ways in which they both managed to bring improvisation into film art.