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The purpose of this paper is to propose a defect detection method of silicone caps positional deviation on flexible printed circuit board (FPCB) of keyboard based on automatic optical inspection.

First, the center of silicone caps of target keyboard FPCB image was extracted as feature points for generating the feature image which is used for registration rigidly with the reference feature image generated from the CAD drawings. Then, a flexible image registration method based on the surrounding-control-center B-splines (SCCB) strategy was proposed, which could correct the flexible deformation of the image generated by FPCB substrate while keeping the pasting deviation information about silicone caps unchanged. Finally, on this basis, a nearest neighbor strategy was proposed to detect the positional deviation of silicone caps.

Experimental results show that the proposed method can effectively detect the positional deviation defect of silicone caps. The G-mean value of the proposed method is 0.941746, which is 0.3 higher compared to that of similar research.

This paper presents a method to detect positional deviation defect of silicone caps on keyboard FPCB. Different from the classic B-spline image registration method, the proposed SCCB method used the neighborhood information of the pixel to be registered selectively to calculate the displacement vector needed for its registration, which overcame the problem that the silicone cap pasting deviation information disappears with the correction of the flexible deformation of the image.

The purpose of this paper is to present a novel nitrile butadiene rubber (NBR) packaging structure, which can solve the problems of the low sensitivity, narrow frequency band and fluctuating frequency response curve of the MEMS bionic vector hydrophone.

A 0.05-mm-thick NBR sound-transparent cap was designed by theoretical analysis and simulation to reduce the signal attenuation caused by the packaging structure, and the frequency band of the hydrophone has been extended to 4 kHz. In this work, the vector hydrophone was fabricated by the MEMS technology and packaged with the NBR sound-transparent cap. The performance indicators were calibrated in the National Defence Underwater Acoustics Calibration Laboratory of China.

The results show that the sensitivity of NBR-packaged hydrophone reaches −170 dB (±2 dB), and the difference is less than 1 dB compared to bare chip. And the frequency band is 50 Hz-4 kHz. The hydrophone also has good directional pattern in the form of an 8-shape, and the pressure-resisting ability is more than 2 MPa.

The packaging structure significantly increases the sensitivity of the hydrophone and broadens the frequency band, providing a new method in the packaging design for MEMS hydrophone.

This paper aims to provide details of recent commercial and academic developments in flexible and soft grippers and considers their impact on emerging robotic markets.

Following an introduction, this paper first considers commercially available anthropomorphic robotic hands and soft grippers. It then discusses a selection of recent research activities and concludes with a brief discussion of the potential of these developments.

Anthropomorphic robotic hands, which seek to mimic the structure and capabilities of the human hand, together with a technologically diverse family of soft grippers have recently have been commercialised. Most are produced by companies which spun-out from academic establishments. A strong body of innovative research continues and involves a wide range of principles and technologies. These gripping technologies are expected to catalyse several new and emerging applications; the most important being in agile manufacturing, particularly when used with collaborative robots (cobots).

This paper provides details of recent developments and research into anthropomorphic hands and soft grippers and an insight into their applications.

Soft robotics is a burgeoning field owing to its high adaptability and safety in human–machine interaction and unstructured environments. However, the feedback control of soft actuators with flexible sensors is still a challenge.

To address this issue, this study proposes an optical fibre-based sensing membrane for the posture measurement of soft pneumatic bending actuators. The major contribution is the development of a flexible sensing membrane with a high sensitivity and repeatability for the feedback control of soft actuators. The characteristics of sensing membrane were analysed. The relationship between wavelength shift and bending curvature was derived. The curvatures of soft actuator were measured at four bending status, and the postures were reconstructed.

The results indicate that the measurement error is less than 2.1% of the actual bending curvature. The sensitivity is up to 212.8 pm/m⁻¹, and the signal fluctuation in repeated measurements is negligible. This approach has broad application prospects in soft robotics, because it makes the optical fibre achieve more strength and compatible with soft actuators, thus improving the sensing accuracy, sensitivity and reliability of fibre sensors.

Different from previous approaches, an optical fibre with FBGs is embedded into a multilayered polyimide film to form a flexible sensing membrane, and the membrane is embedded into a soft pneumatic bending actuator as the smart strain limited layer which is able to measure the posture in real time. This approach makes the optical fibre stronger and compatible with the soft pneumatic bending actuator, and the sensing accuracy, sensitivity and reliability are improved. The proposed sensing configuration is effective for the feedback control of the soft pneumatic bending actuators.

This paper aims to provide an insight into recent developments in adhesive technology.

Following a brief introduction, this paper discusses recent developments in biomimetic adhesives, the use of nanomaterials and “smart” adhesive technology.

Biomimetic dry adhesive technology has advanced very rapidly in recent years and techniques to mass‐produce these materials are now under development. The use of nanomaterials is being investigated widely and recent research suggests that adhesives with enhanced mechanical, thermal and electrical properties will emerge. Smart adhesives, such as switchable types which can be triggered to bond and de‐bond in response to physical or chemical stimuli are under development and some are already available commercially. These will contribute to product disassembly and recycling.

This paper provides a review of recent R&D into three fields of adhesive technology that are presently attracting strong interest.

Until recently liquid chromatography has been a somewhat neglected branch of science. However, the availability of precision equipment, and even complete instruments, has made possible liquid chromatography separations of a more advanced nature. For example, suitable detectors have been developed, and pumps are available which deliver accurate volumes of solvent under pressure.

An introduction to the topic of aqueous silicone resin coating systems for exterior masonry. Concentrates on applications in the construction industry.

Finzel (American Paint and Coatings Journal, January 19 (1981) p. 19; Metal Finishing, June (1982) p. 49) has authored two review articles on silicones. He points out that silicones are mature products having first been introduced over thirty years ago. Their major use in the coatings field is for maintenance to provide protection against weathering, temperature extremes, and corrosive atmospheres. Silicones, when combined with other vehicles, impart increased resistance to moisture, chemicals, ultraviolet degradation, thermal shock, chalking, fading, and peeling. The major use, however, for silicones is for high temperature coatings as reactive intermediates and as paint additives.