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The pressure sensors can convert external pressure or mechanical deformation into electrical power and signal, which cannot only detect pressure or strain changes but also harvest energy as a self-powered sensor. This study aims to develop a self-powered flexible pressure sensor based on regular nanopatterned polymer films.

In this paper, the self-powered flexible pressure sensor is mainly composed of two nanopatterned polymer films and one conductive electrode layer between them, which is a sandwich structure. The regular nanostructures increase the film roughness and contact area to enhance the friction effect. To enhance the performance of the pressure sensor, different nanostructures on soft polymer sensitive layers are fabricated using UV nanoimprint lithography to generate more triboelectric charges.

Finally, the self-powered flexible pressure sensor is prepared, which consists of sub-200 nm resolution regular nanostructures on the surface of the elastic layer and an indium tin oxide electrode thin film. By converting the friction mechanical energy into electrical power, a maximum power of 423.8 mW/m2 and the sensitivity of 0.8 V/kPa at a frequency of 5 Hz are obtained, which proves the excellent sensing performance of the sensor.

The acquired electrical power and pressure signal by the sensor would be processed in the signal process circuit, which is capable of immediately and sustainably driving the highly integrated self-powered sensor system. Results of the experiments show that this new pressure sensor is a potential method for personal pressure monitoring, featured as being wearable, cost-effective, non-invasive and user-friendly.

A self-adaptive piston is designed for the compressional gas cushion press nanoimprint lithography system. It avoids the lube pollution and high wear of traditional piston.

The self-adaptive piston device consists of symmetrical piston bodies, piston rings and other parts. The two piston bodies are linked by a ball-screw. The locking nut adjusts the distance between two piston bodies to avoid the piston rings from being stuck. The piston rings are placed between two piston bodies.

The simulation results based on COMSOL indicate that cylinder vibration caused by self-adaptive piston is 15.9 times smaller than the one caused by a traditional piston.

The self-adaptive piston is superior to the traditional piston in decreasing cylinder vibration.

Generally, the motion range of the micro scale operation is within several hundreds of microns, and the conventional joints cannot satisfy the requirements due to manufacturing and assembling errors, hysteresis and backlash in the joints. The paper aims to discuss these issues.

The following issues should be considered: a micromanipulation stage should be designed using a small-dimensional scale driven by the small size of piezoelectric actuator and the components can be replaced due to fatigue failure caused by repeated cyclic loading. This paper proposes a modular design of a flexure-based 2-DOF precision stage made using aluminum (T6-7075) material and Acrylonitrile Butadiene Styrene plastic material. The piezoelectric actuator is adopted to drive the stage for the fast response and large output force. To compensate the stroke of piezoelectric actuator, a bridge-type amplifier is designed with optimized structure.

The simulation results validate the advantages of modular positioning stage fabricated by two different materials.

The stage can be used in micro scale precision’s applications. If it will be used in nanoscale precision, then some sensors in nanoscale of measurement should be used.

The designed stage can be used in biomedical engineering, such as cell injection testing, etc.

The designed stage will be used in micro/nanoengineering field, such as micro/nanomanufacturing or assembly, manipulation of cell, etc., which will push forward high technology to a higher level.

Two kinds of materials have been selected to make the positioning stage, which are seldomly found in literature on compliant mechanism field. A modular design concept is proposed for the positioning stage design.

This paper aims to discuss the new applications enabled by printed sensors.

The paper discusses how silicon‐based sensors are manufactured using the time‐consuming, expensive, and complicated fabrication process of traditional semiconductor devices and shows what is needed in order to produce such new devices with the advantages of printed sensors.

With new materials, new processing technologies and a new manufacturing process, thin, flexible, lightweight, cost‐effective sensors are made possible through the power of printed semiconductors.

This paper should be of value in terms of understanding the pros of printed semiconductors and the resulting sensors which have a number of unique mechanical, electrical, and optical properties.

The purpose of this paper is to provide a technical review of recent nanosensor research.

This paper describes a number of nanosensor research themes and recent development activities, with an emphasis on work conducted or reported since 2006. It considers a range of emerging nanosensing technologies and two specific areas of application.

This paper shows that nanosensor technology is developing rapidly and is the subject of a global research effort. Technologies such as nano‐electromechanical system, nano‐opto‐electromechanical system, nanophotonics and the combination of nanotechnology with microtechnology offer prospects to yield sensors for a wide range of chemical, biochemical and physical variables in applications which include healthcare, defence and homeland security, environmental monitoring and light sensing and imaging.

This paper provides a technically detailed, up‐to‐date account of recent nanosensor research.

The processing techniques and materials utilized in the fabrication of a two-terminal electrostatically actuated micro-electro-mechanical cantilever-arrayed device used for radio frequency tuning applications are presented in this work. The paper aims to discuss these issues.

The process, which is based on silicon surface micromachining, uses spin-coated photoresist as the sacrificial layer underneath the electroplated gold structural material and an insulating layer of silicon dioxide, deposited using plasma enhanced chemical vapour deposition (PECVD), to avoid a short circuit between the cantilever and the bottom electrode in a total of six major fabrication steps. These included the PECVD of the silicon dioxide insulating layer, optical lithography to transfer photomask layer patterns, vacuum evaporation to deposit thin films of titanium (Ti) and gold (Au), electroplating of Au, the dry release of the cantilever beam arrays, and finally the wafer dicing to split the different micro devices. These process steps were each sub-detailed to give a total of 14 micro-fabrication processes.

Scanning electron microscope images taken on the final fabricated device that was dry released using oxygen plasma ashing to avoid stiction showed 12 freely suspended micro-cantilevered beams suspended with an average electrostatic gap of 2.29±0.17 μm above a 4,934±3 Å thick silicon dioxide layer. Preliminary dimensional measurements on the fabricated devices revealed that the cantilevers were at least 52.06±1.93 μm wide with lengths varying from 377.97±0.01 to 1,491.89±0.01 μm and were at least 2.21±0.05 μm thick.

The cantilever beams used in this work were manufactured using electroplated gold, and photoresist was used as a sacrificial layer underneath the beams. Plasma ashing was used to release the beams. The beams were anchored to a central electrode and each beam was designed with varying length.

Nano‐imprint forming (NIF) is a manufacturing technology capable of achieving high resolution, low‐cost and high‐throughput fabrication of fine nano‐scale structures and patterns. The purpose of this paper is to use modelling technologies to simulate key process steps associated with the formation of patterns with sub‐micrometer dimensions and use the results to define design rules for optimal imprint forming process.

The effect of a number of process and pattern‐related parameters on the quality of the fabricated nano‐structures is studied using non‐linear finite element analysis. The deformation process of the formable material during the mould pressing step is modelled using contact analysis with large deformations and temperature dependent hyperelastic material behaviour. Finite element analysis with contact interfaces between the mould and the formable material is utilised to study the formation of mechanical, thermal and friction stresses in the pattern.

The imprint pressure, temperature and the aspect ratio of grooves which define the pattern have significant effect on the quality of the formed structures. The optimal imprint pressure for the studied PMMA is identified. It is found that the degree of the mould pattern fulfilment as function of the imprint pressure is non‐linear. Critical values for thermal mismatch difference in the CTE between the mould and the substrate causing thermally induced stresses during cooling stage are evaluated. Regions of high stresses in the pattern are also identified.

Design rules for minimising the risk of defects such as cracks and shape imperfections commonly observed in NIF‐fabricated nano‐structures are presented. The modelling approach can be used to provide insights into the optimal imprint process control. This can help to establish further the technology as a viable route for fabrication of nano‐scale structures and patterns.

In some three-dimensional (3D) printing application scenarios, e.g., model manufacture, it is necessary to print large-sized objects. However, it is impossible to implement large-size 3D printing using a single projector in digital light processing (DLP)-based mask projection 3D printing because of the limitations of the digital micromirror device chips.

A multi-projector DLP with energy homogenization (EHMP-DLP) scheme is proposed for large-size 3D printing. First, a large-area printing plane is established by tiling multiple projectors. Second, the projector set’s tiling pattern is obtained automatically, and the maximum printable plane is determined. Third, the energy is homogenized across the entire printable plane by adjusting gray levels of the images input into the projectors. Finally, slices are automatically segmented based on the tiling pattern of the projector set, and the gray levels of these slices are reassigned based on the images of the corresponding projectors.

Large-area high-intensity projection for mask projection 3D printing can be performed by tiling multiple DLP projectors. The tiled projector output energies can be homogenized by adjusting the images of the projectors. Uniform ultraviolet energy is important for high-quality printing.

A prototype device is constructed using two projectors. The printable area becomes 140 × 210 mm from the original 140 × 110 mm.

The proposed EHMP-DLP scheme enables 3D printing of large-size objects with linearly increasing printing times and high printing precision. A device was established using two projectors to practice the scheme and can easily be extended to larger sizes by using more projectors.