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To present the specifications and the technologies underpinning some new high‐speed cameras, and explore their applications.
Abstract
Purpose
To present the specifications and the technologies underpinning some new high‐speed cameras, and explore their applications.
Design/methodology/approach
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.
Findings
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.
Originality/value
Monitors the progress of imaging technology and describes its current capabilities to the interested reader.
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Keywords
To report on specialist software developed for the management and analysis of high‐speed imaging.
Abstract
Purpose
To report on specialist software developed for the management and analysis of high‐speed imaging.
Design/methodology/approach
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.
Findings
High‐speed imaging is a powerful technique for monitoring, maintaining and trouble‐shooting assembly automation equipment.
Originality/value
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.
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To present two non‐contact methods of measuring vibrations and impact events.
Abstract
Purpose
To present two non‐contact methods of measuring vibrations and impact events.
Design/methodology/approach
The paper concentrates on the practical capabilities and underlying technology of commercial high‐speed CMOS cameras and laser Doppler vibrometers.
Findings
The instruments are used to analyse modes of failure and to test quality in a very wide range of products. They are also used to develop safety and protective devices, and to study natural phenomena.
Originality/value
A practical guide to the tools available, with some example applications of interest to production engineers.
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Piotr Krupski and Henryka Danuta Stryczewska
The research purpose of this paper is to confirm that internal overvoltages in the push–pull power inverter can be used to improve the discharge ignition in the gliding arc…
Abstract
Purpose
The research purpose of this paper is to confirm that internal overvoltages in the push–pull power inverter can be used to improve the discharge ignition in the gliding arc discharge (GAD) plasma reactor.
Design/methodology/approach
Investigations are based on the acquisition of voltage changes that occur together with the development of the discharge column and the imaging the GAD with the use of a high-speed camera.
Findings
The power supply has the distinctive feature of not having the switching overvoltages completely extinguished, as it is in typical push–pull inverters. The overvoltages still exist but only dangerous peaks are cut off. The remaining ones, of a dumped resonance character (Figure 3), are transferred to the secondary coil of the transformer. Correctly shaped overvoltages are used for ignition improvement in the GAD reactor.
Practical implications
GAD plasma reactors have many applications for pollution control, disinfection and sterilization of surfaces and for plasma deposition, surface functionalization, as well as in agricultural and medical treatment. Investigations prove the push–pull inverter’s advantages in comparison with the transformer-type power supply. Properly configured push–pull inverters have good ignition properties and control options, allowing to generate, desirable for many applications, homogeneous non-thermal plasma.
Originality/value
The idea of using switching overvoltages in transistors of push–pull switching-mode power supplies is new and has not been previously used to improve discharges ignition in a non-thermal plasma reactor.
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Zixin Liu, Yongqiang Yang, Di Wang, Jie Chen, Yunmian Xiao, Hanxiang Zhou, Ziyu Chen and Changhui Song
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.
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Practical implications
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.
Originality/value
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.
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Guanchen Liu, Dongdong Xu, Zifu Shen, Hongjie Xu and Liang Ding
As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous…
Abstract
Purpose
As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.
Design/methodology/approach
Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.
Findings
In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.
Originality/value
With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.
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Reviews vision systems exhibited at the Manufacturing Week Exhibition held in the NEC, Birmingham. Highlights systems that exemplify the trend towards standardized off‐the‐shelf…
Abstract
Reviews vision systems exhibited at the Manufacturing Week Exhibition held in the NEC, Birmingham. Highlights systems that exemplify the trend towards standardized off‐the‐shelf units, and the increasing use of PC‐based hardware and software running in Microsoft Windows. Grey‐scale image processing is becoming more widespread and replacing binary blob analysis techniques. This makes the systems more resilient to ambient conditions and increases the hardiness for industrial application. Gives examples of some of the applications of these systems.
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Sandra Matarneh, Faris Elghaish, Amani Al-Ghraibah, Essam Abdellatef and David John Edwards
Incipient detection of pavement deterioration (such as crack identification) is critical to optimizing road maintenance because it enables preventative steps to be implemented to…
Abstract
Purpose
Incipient detection of pavement deterioration (such as crack identification) is critical to optimizing road maintenance because it enables preventative steps to be implemented to mitigate damage and possible failure. Traditional visual inspection has been largely superseded by semi-automatic/automatic procedures given significant advancements in image processing. Therefore, there is a need to develop automated tools to detect and classify cracks.
Design/methodology/approach
The literature review is employed to evaluate existing attempts to use Hough transform algorithm and highlight issues that should be improved. Then, developing a simple low-cost crack detection method based on the Hough transform algorithm for pavement crack detection and classification.
Findings
Analysis results reveal that model accuracy reaches 92.14% for vertical cracks, 93.03% for diagonal cracks and 95.61% for horizontal cracks. The time lapse for detecting the crack type for one image is circa 0.98 s for vertical cracks, 0.79 s for horizontal cracks and 0.83 s for diagonal cracks. Ensuing discourse serves to illustrate the inherent potential of a simple low-cost image processing method in automated pavement crack detection. Moreover, this method provides direct guidance for long-term pavement optimal maintenance decisions.
Research limitations/implications
The outcome of this research can help highway agencies to detect and classify cracks accurately for a very long highway without a need for manual inspection, which can significantly minimize cost.
Originality/value
Hough transform algorithm was tested in terms of detect and classify a large dataset of highway images, and the accuracy reaches 92.14%, which can be considered as a very accurate percentage regarding automated cracks and distresses classification.
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Radek Doubrava, Martin Oberthor, Petr Bělský and Jan Raška
The purpose of this paper is to describe the approach for the design of a jet engine composite air inlet for a new generation of jet trainer aircraft from the perspective of…
Abstract
Purpose
The purpose of this paper is to describe the approach for the design of a jet engine composite air inlet for a new generation of jet trainer aircraft from the perspective of airworthiness requirements regarding high-speed impact resistance.
Design/methodology/approach
Validated numerical simulation was applied to flat test panels. The final design was optimised and verified by validated numerical simulation and verified by testing on a full-scale demonstrator. High-speed camera measurement and non-destructive testing (NDT) results were used for the verification of the numerical models.
Findings
The test results of flat test panels confirmed the high durability of the composite structure during inclined high-speed impact with a near-real jet inlet load boundary condition.
Research limitations/implications
Owing to the sensitivity of the composite material on technology production, the results are limited by the material used and the production technology.
Practical implications
The application of flat test panels for the verification and tuning of numerical models allows optimised final design of the air inlet and reduces the risk of structural non-compliance during verification tests.
Originality/value
Numerical models were verified for simulation of the real composite structure based on high-speed camera results and NDT inspection after impact. The proposed numerical model was simplified for application in a real complex design and reduced calculation time.
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Abstract
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