Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 3

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
The sheet metal surface crack detection during manufacturing is an essential issue because of both the product quality and process productivity. Development of solutions to eliminate defective products during the metal forming process is crucial for the smooth production and for developing an appropriate tool geometry in the initial phase of the process. Currently, the methods of surface crack detection used in the industry are mostly related to visual inspection. These are methods that require operators of industrial facilities considerable attention and effort to capture emerging discontinuities on the sheet metal surface. Also, this situation results increase in the duration of the specific operations of stamping and significantly reduces productivity. Therefore, an industrial application of a non-contact laser technique that simultaneously provides the results of the speckle imaging is presented. The authors demonstrate a specially designed machine vision system along with experimental tools for the stamping operation. Proposed solution uses the phenomenon of speckle pattern that appears in the image of the investigated sheet surface produced by the laser beam emission. In this method, coherent laser light is emitted to the surface, where a speckle pattern is generated due to scatter reflection from the sheet metal surface and then, shift-and-add technique and image processing is applied. The proposed measurement technique consists, initially, of making a sequence of images of the tested object for the moving surface of the sheet. Secondly, the object's displacement quantity in each image is determined, and the position is corrected. The test object in each image is moved to the starting position, and all images are superimposed. It allows to obtain a high-quality image with visible surface defects. Finally, the dynamically changing speckle pattern intensity is evaluated using Gaussian-of-Laplacian edge detection to investigate a surface crack location due to the surface discontinues and light scattering. This process is recommended for machine vision imaging of distant objects, which works well in industrial conditions as well as online analysis. Also, from the speckle size measurement, an experimental procedure is employed to verify the best condition for vision system resolution.
EN
Purpose: In the development of ideas for Industry 4.0, information about the element production cycle has become more and more important. Knowledge of the subsequent forming processes, determination of the machine on which the process has been carried out and of the type and wear of the tool, leads to smart production management, which plays an increasingly important role in the metal forming industry. To meet the current expectations for these challenges, an advanced technology needs to be introduced for monitoring the manufacturing processes by deploying flexible solutions. This technology must include, but not be limited to, identifying and tracking the product using laser marking. Design/methodology/approach: Laser marking allows a permanent mark in the form of a barcode to be applied to the sheet metal surface. Commonly used marking methods and the condition of the sheet metal surface can affect the marking contrast. This paper presents a concept for recording individual stages of sheet metal forming and determination of the impact of the laser marking technology on the contrast of the applied barcode. To ensure accurate control of the deformation stages, the bulging process of the spherical dome has been used as an example. Findings: Analysis of the influence of laser marking method on the barcode recognition accuracy can contribute to the development of smart management of the production process according to the idea of Industry 4.0. Research limitations/implications: A large plastic deformation has been applied to the sheet metal surface and no limitation in a barcode reading process (using vision scanning technology) was indicated. Also, the geometry deformation (different angle view of the CCD camera) of the barcode image has introduced no additional problems with a barcode reading. Originality/value: The optimal parameters of a laser marking technique for barcode marking, which are critical for the material that is subjected to metal forming operations that deform it, have been studied. The results shows that traceability is an attractive solution for tracking technological data in the production chain for a single-shaped product.
EN
In this article, the authors focused on the widely used aluminium extrusion technology, where the die quality and durability are the essential factors. In this study, detailed solutions in the three-key area have been presented. First is applying marking technology, where a laser technique was proposed as a consistent light source of high power in a selected, narrow spectral range. In the second, an automated and reliable identification method of alphanumeric characters was investigated using an advanced machine vision system and digital image processing adopted to the industrial conditions. Third, a proposed concept of online tool management was introduced as an efficient process for properly planning the production process, cost estimation and risk assessment. In this research, the authors pay attention to the designed vision system’s speed, reliability, and mobility. This leads to the practical, industrial application of the proposed solutions, where the influence of external factors is not negligible.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.