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With a surge in technological advancements and the needs of diverse communities such as consumers, military and navy, the textile industry is shifting its focus to fabrication of next-generation textiles that not only meet the basic conventional requirements, but also serve a host of other functions. In this pursuit of fabricating next-generation textiles, called here e-textiles (electronic textiles), a novel technique is presented to produce nanocomposite fabrics made from carbon nanotubes (CNTs) with enhanced sensing capabilities. Catering to the ever increasing demand of improved sensors, this work discusses the electrospinning fabrication scheme that has been employed to develop novel CNT-based piezoelectric strain sensors. The resulting sensors have been characterized by performing structural vibration experiments to evaluate their strain-sensing performance. When these new CNT-based piezopolymer composites are electrospun into smart fabrics, the strain-sensing ability (as measured by voltage across the sensor) is increased by a dramatic 35 times, from 2.4 to 84.5 mV for 0.05 wt% of the nanotubes. The dominant mechanism responsible for such improvement is found to be the alignment of dipoles in the piezoelectric material. Such alignment is mainly attributed due to ability of the electrospinning process to generate very thin fibers from polymer-nanotube solution. The direct and reverse conversion of electrical energy into mechanical energy in the proposed sensors can create a platform for developing next-generation smart fabric with applications in membrane structures, distributed shape modulation and energy harvesting.

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The atomic force microscope (AFM) system has evolved into a useful tool for direct measurements of microstructural parameters and intermolecular forces at nanoscale level with atomic-resolution characterization. Typically, these microcantilever systems are operated in three open-loop modes; non-contact mode, contact mode, and tapping mode. In order to probe electric, magnetic, and/or atomic forces of a selected sample, the non-contact mode is utilized by moving the cantilever slightly away from the sample surface and oscillating the cantilever at or near its natural resonance frequency. Alternatively, the contact mode acquires sample attributes by monitoring interaction forces while the cantilever tip remains in contact with the target sample. The tapping mode of operation combines qualities of both the contact and non-contact modes by gleaning sample data and oscillating the cantilever tip at or near its natural resonance frequency while allowing the cantilever tip to impact the target sample for a minimal amount of time. Recent research on AFM systems has focused on many fabrication and manufacturing processes at molecular levels due to its tremendous surface microscopic capabilities. This paper provides a review of such recent developments in AFM imaging systems with emphasis on operational modes, microcantilever dynamic modeling and control. Due to the important contributions of AFM systems to manufacturing, this paper also provides a comprehensive review of recent applications of different AFM systems in these important areas.