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To report on specialist software developed for the management and analysis of high‐speed imaging.

Reviews the background of the company, and its range of high‐speed cameras. Gives details of two software packages used to display and analyse events in image sequences.

High‐speed imaging is a powerful technique for monitoring, maintaining and trouble‐shooting assembly automation equipment.

Makes assembly engineers aware of the potential of high‐speed imaging. Techniques originally developed for the motor industry have a wide applicability in manufacturing and production monitoring.

To present the specifications and the technologies underpinning some new high‐speed cameras, and explore their applications.

Describes the industrial, military and other applications of high‐speed imaging. Traces the recent technical developments in sensors for visible and infrared light. Then describes some specific high‐speed cameras.

CMOS sensors have now taken over from CCD in high‐speed visible cameras. Microbolometers have made low‐cost uncooled cameras available for infrared imaging. Applications range from serious research and development topics, such as air‐bag and seat‐belt performance and combustion studies, to investigations of natural phenomena and analysis of sports equipment.

Monitors the progress of imaging technology and describes its current capabilities to the interested reader.

Quantitative understanding of the temperatures, gradients and heating/cooling rates in and around the melt pool in laser powder bed fusion (L-PBF) is essential for simulation, monitoring and controls development. The research presented here aims to detail experiment design and preliminary results of high speed, high magnification, in-situ thermographic monitoring setup on a commercial L-PBF system designed to capture temperatures and dynamic process phenomena.

A custom door with angled viewport was designed for a commercial L-PBF system which allows close access of an infrared camera. Preliminary finite element simulations provided size, speed and scale requirements to design camera and optics setup to capture melt pool region temperatures at high magnification and frame rate speed. A custom thermal calibration allowed maximum measurable temperature range of 500°C to 1,025°C. Raw thermographic image data were converted to temperature assuming an emissivity of 0.5. Quantitative temperature results are provided with qualitative observations with discussion regarding the inherent challenges to future thermographic measurements and process monitoring.

Isotherms around the melt pool change in size depending on the relative location of the laser spot with respect to the stripe edges. Locations near the edges of a stripe are cooled to lower temperatures than the center of a stripe. Temperature gradients are highly localized because of rough or powdery surface. At a specific location, temperatures rise from below the measurable temperature range to above (<550°C to >1100°C) within two frames (<1.11 m/s). Particle ejection is a notable phenomenon with measured ejection speeds >11.7 m/s.

Several works are detailed in the Introduction of this paper that detail high-speed visible imaging (not thermal imaging) of custom or commercial LBPF processes, and lower-speed thermographic measurements for defect detection. However, no work could be found that provides calibrated, high-speed temperature data from a melt-pool monitoring configuration on a commercial L-PBF system. In addition, the paper elucidates several sources of measurement uncertainty (e.g. calibration, emissivity and time and spatial resolution), describes inherent measurement challenges based on observations of the thermal images and discusses on the implications to model validation and process monitoring and control.

This study aims to compare cavitation shapes between the simulating test rig and the engines to strengthen the findings that were first observed in the simplified experiments. Different forms of cavitation were identified, and their shape and size (length and width) were dictated from reciprocating speed and viscosity of the lubricant. Cavitation degrades performance in engineering applications and its effect is that it alters the oil film pressure.

Lubricant formulations were used for parametric study as well as different operating testing parameters in a simulating test rig and single cylinder engines with visualisation windows. An algorithm was used for extracting cavitation data from imaging, and comparison was made.

Similar phenomena at the simulating test rig and the engine were investigated and compared. The effect of different operating conditions was assessed along with the variations produced from the parametric lubricant study.

Engine results are limited due to manufacturing difficulties of visualisation windows and oil starvation. Firing tests are another difficult challenge as the modified section pressure is under more pressure and the window view is affected by combustion process. Limited pictures can be captured before cleaning is required. A lubricant manufacturer has to provide data regarding the chemistry of the lubricants.

The effect of cavitation in piston ring lubrication along with variable operating and lubricant parameters is further studied with quantification of cavitation results through image processing. These forms of cavities are affected by lubricant properties and operating conditions. A link between viscosity, cavitation, shear thinning properties, oil film thickness (OFT) and friction is given.

The purpose of this paper is to offer an introduction to the technological advances of the complementary metal–oxide–semiconductor (CMOS) image sensors along the past decades. The authors review some of those technological advances and examine potential disruptive growth directions for CMOS image sensors and proposed ways to achieve them.

Those advances include breakthroughs on image quality such as resolution, capture speed, light sensitivity and color detection and advances on the computational imaging.

The current trend is to push the innovation efforts even further, as the market requires even higher resolution, higher speed, lower power consumption and, mainly, lower cost sensors. Although CMOS image sensors are currently used in several different applications from consumer to defense to medical diagnosis, product differentiation is becoming both a requirement and a difficult goal for any image sensor manufacturer. The unique properties of CMOS process allow the integration of several signal processing techniques and are driving the impressive advancement of the computational imaging.

The authors offer a very comprehensive review of methods, techniques, designs and fabrication of CMOS image sensors that have impacted or will impact the images sensor applications and markets.

The purpose of this paper is to study the movement characteristics of micro drill bit during entry period in printed circuit board (PCB) high-speed drilling and to present an effective method to conduct quantitative analysis of the wandering of drill bit based on high-speed video capturing.

Based on the high-speed camera technology, experiments are conducted to get a series of time sequence images and the wandering of micro drill tip and the radial run-out of drill body, and the max-deformation of drill bit are calculated by using a quantitative analysis method. Finally, the movement characteristics of micro drill bit during entry drilling period PCB high-speed drilling are evaluated.

With the increasing spindle speed, the radial run-out of drill body decreases gradually, whereas the wandering amplitude of the drill point gradually increases; micro drill bit itself has an ability of positioning deviation correction after contacting the entry sheet; the feed rate within a certain range could slightly worsen the deformation of drill tip at the instant of impingement.

With the improvement of spindle speed, the camera’s shooting speed needed will increase accordingly, thus, the resolution of the pictures will decline, which always affects the analysis precision.

A series of effective methods to conduct quantitative analysis of the wandering micro drill bit by using high-speed camera technology is presented; a reference for the optimization of micro-hole drilling is provided.

Recently great interest has developed for a high speed, flexible machine vision system which can accurately determine solder paste and component placement for both process verification and quality control inspection. Present SMT inspection systems must cope with the unpredictable appearance of components and backgrounds and are often used only to determine presence and absence. This paper describes a new approach which combines greyscale data with a three‐dimensional map of the board under test. Originally this method was proposed as a robust technique for locating components in low contrast greyscale images. However, experience working with manufacturers and developers of placement equipment has shown that emerging SMT inspection requirements indicate the importance of three‐dimensional information. In addition to the detection of components and measurement of orientation, examples are shown of solder paste volume measurements, lead co‐planarity, and tombstone effect detection.

This study aims to investigate the influence of the gas-flow field distribution and design on the parts quality of 316L stainless steel and the vapor–spatter behavior.

Based on the hot-wire wind speed test method, the exact value of the gas velocity at different locations was accurately measured to establish the effect on the porosity and the mechanical properties of the parts. The influence of the placement of single or dual blow screens on the performance of the parts quality was also studied. Through scanning electron microscope and energy dispersive spectrometer, high-speed photography and other methods, the influence mechanism was explained.

It was found that too high or too low gas velocity both play a negative role, for 316L stainless steel, the range of 1.3–2.0 m/s is a suitable gas field velocity during the multilaser powder bed fusion process. And printing quality using dual blow screens is better than single.

The optimization of gas field design and optimal gas velocity (1.3–2.0 m/s) applied during laser melting can improve the quality of ML-PBF of 316L stainless steel.

This study showed the influence of the gas field on the spatter–vapor in the process during ML-PBF, and the unfavorable gas field led to the formation of pores and unmelted powders.

The purpose of this paper is to investigate technologies improving image quality and understanding in life‐science microscopy.

The new technique of high‐content analysis is described, along with the equipment available from various manufacturers. Advances in fluorescence imaging and confocal microscopy are then addressed. The paper concludes by reporting a powerful 3D visualisation package, and equipment for networked viewing of high‐resolution microscopy images.

High‐content analysis has developed rapidly in the last four or five years, due largely to improvements in the software interface. Automation and powerful software acquire and manage vast quantities of data, allowing scientists experiment afresh on archived images. Improvements in laser scanning techniques and the emergence of microLED arrays assist microscopy imaging of live cells, whilst techniques giving high‐spectral discrimination improve image understanding.

The paper describes how image‐processing technologies are assisting the work of cell biologists. Stresses the importance of software and hardware design to user uptake, which is relevant for all engineers.

This paper aims to overview the current status of development and application of digital image processing technology used for the yarn hairiness evaluation.

Digital image processing technology is one of the new methods used for the yarn detection, which can be used for the digital characterization and objective evaluation of yarn appearance. The comparison between the traditional detection methods and this new developed method was made and analyzed.

Compared with the traditional methods, image-based methods have the advantages of being objective, fast and accurate. Therefore, it was proved that digital image processing techniques should be a new trend in terms of the yarn appearance evaluation.