Roll-to-roll (R2R) printing has been pursued as a commercially viable high-throughput technology to manufacture flexible, disposable, and inexpensive printed electronic devices. However, in recent years, pessimism has prevailed because of the barriers faced when attempting to fabricate and integrate thin film transistors (TFTs) using an R2R printing method. In this paper, we report 20 × 20 active matrices (AMs) based on single-walled carbon nanotubes (SWCNTs) with a resolution of 9.3 points per inch (ppi) resolution, obtained using a fully R2R gravure printing process. By using SWCNTs as the semiconducting layer and poly(ethylene terephthalate) (PET) as the substrate, we have obtained a device yield above 98%, and extracted the key scalability factors required for a feasible R2R gravure manufacturing process. Multi-touch sensor arrays were achieved by laminating a pressure sensitive rubber onto the SWCNT-TFT AM. This R2R gravure printing system overcomes the barriers associated with the registration accuracy of printing each layer and the variation of the threshold voltage (Vth). By overcoming these barriers, the R2R gravure printing method can be viable as an advanced manufacturing technology, thus enabling the high-throughput production of flexible, disposable, and human-interactive cutting-edge electronic devices based on SWCNT-TFT AMs.

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Research on the improvement of efficiency in the manufacturing industry is underdeveloped partly because of the ambiguous objectives of the technical development of efficiencies in terms of energy consumption reduction. Consequently, the technical development of high-efficiency techniques that consider the whole manufacturing system is rarely addressed in industrial research. For this reason, this report aims to find the patterns in, and the definitions of, the technologies that will lead to efficiency improvement in the entire manufacturing industry by thoroughly investigating the literature about energy consumption reduction strategies, energy policies, and the state-of-the-art for energy-saving methods that are being pursued currently in several major countries. Through this study, the necessity and importance of the foregoing three items have been identified, and a way of defining the productivities of an energy-saving manufacturing system distinct from those of conventional manufacturing systems was attempted. It is also shown that the development of energy-saving and energy-harvesting technologies for all industrial sectors has emerged as a herald of economic growth in the near future.

simulation training, communication, and immersive entertainment. Yet, the utility of haptics is currently limited; moreover, it is challenging to produce the large-area, distributed signals required to mimic natural touch.It would be desirable for haptic actuators to generate large ranges of forces and displacements over short time scales, in a compact form factor in the case of wearable haptics. This dynamism is required because the structures such as the skin and elements of the musculoskeletal system are highly stretchable. Moreover, they are teeming with mechanosensory neurons that can perceive sub-micron surface features and macroscale displacements, with reaction times in milliseconds. [3,5] Thus, to accommodate this dynamism and sensitivity, an exceptionally versatile suite of materials and tools is required to realize the entire range of haptic perception.Haptic perception can be divided into two parts: the tactile and kinesthetic senses. [6][7][8] The tactile sense involves the nerve endings in the skin to detect contact, texture, and vibration. The kinesthetic sense is the awareness of the body position and involves structures located in the musculoskeletal system to sense force and motion. For example, to emulate the feeling of grasping a cup, a haptic system would need to trigger both tactile and kinesthetic senses. That is, pressure would be applied on the fingers to indicate contact, and other actuators located at the joints of the fingers would stiffen to produce resistance against moving into the space occupied by the cup. In comparison to visual or auditory inputs aiming at localized organs of eyes and ears, haptic systems require distributed inputs covering the body. The complexity involved to simulate haptic signals over large area, with sufficient spatial and temporal resolution and high dynamic range, has been a considerable challenge and thus presents exciting research opportunities.Conventional micro-electromechanical system (MEMS) has been used to implement vibrational feedback, which is the most common type of haptic effect in commercial devices today. However, fabrication techniques for MEMS are catered toward micrometer length scales and hence research is still needed to scale up MEMS assembly [9,10] for large, customized human interfaces. To realize many other promising haptic modalities, new materials and processing technologies are being explored to make devices that improve haptic realism and scalability for mass manufacturing.Haptic actuators generate touch sensations and provide realism and depth in human-machine interactions. A new generation of soft haptic interfaces is desired to produce the distributed signals over large areas that are required to mimic natural touch interactions. One promising approach is to combine the advantages of organic actuator materials and additive printing technologies. This powerful combination can lead to devices that are ergonomic, readily customizable, and economical for researchers to explore potential benefits and create new haptic applications...

In situ techniques to measure the drop-on-demand (DOD) drop formation curve and the instantaneous jetting speed curve are developed such that ligament behavior and satellite behavior of inkjet droplets can be analyzed effectively. It is known that the droplet jetting behavior differs by ink properties and the driving waveform voltage. In this study, to reduce possible droplet placement errors due to satellite drops or long ligaments during printing, waveform effects on drop formation are investigated based on the measured DOD drop formation curve and the instantaneous jetting speed curve. Experimental results show that a dwell time greater than the so-called efficient dwell time was effective in reducing placement errors due to satellite drops during the printing process.

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