Wyniki wyszukiwania - BazTech

1

Alternative Security of the Combat Readiness Recovery Using 3D Printing and Reverse Engineering

Augustyn Sławomir, Kowalski Rafał

Safety & Defense

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2023

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2

40--51

EN

Disrupting spare parts supply chains can harm the smooth running of an organization. In the case of military vehicles, weapons or other types of equipment used on the battlefield, this is a serious threat that may result in the inability to continue some tactical operations. An ad hoc way to maintain the ability to take action while the appropriate spare parts are delivered and to improve damaged devices may be to produce the damaged components locally. Such a temporary solution is possible for relatively simple elements whose structure, mechanical properties and principle of operation can be determined on a reverse engineering basis. This article describes the concept of alternative solutions for temporarily repairing damaged devices by producing spare parts in mobile specialized production subunits. This paper characterizes the types of 3D printing, contemporary examples of use in foreign armies, priorities of international alliances related to 3D printing, and a case study of repairing an unmanned aircraft by means of 3D printing. Using the experience and knowledge of foreign armies, adapting the possibilities of 3D printing applications to one's own needs, defining legal regulations and creating properly equipped subunits makes it possible to implement the presented concept. Creating conditions for implementing the described concept facilitates the production of a suitable product range in peace, crisis or conflict situations, which may significantly contribute to increasing the level of readiness of the national defense systems.

2

Accuracy of virtual rhinomanometry

Karbowski Krzysztof, Kopiczak Bartosz, Chrzan Robert, Gawlik Jolanta, Szaleniec Jolanta

Polish Journal of Medical Physics and Engineering

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2023

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Vol. 29, Iss. 1

59--72

EN

Introduction: This paper describes the results of research aimed at developing a method of otolaryngological diagnosis based on computational fluid dynamics, which has been called Virtual Rhinomanometry. Material and methods: Laboratory studies of airflows through a 3D printed model of nasal cavities based on computed tomography image analysis have been performed. The CFD results have been compared with those of an examination of airflow through nasal cavities (rhinomanometry) of a group of 25 patients. Results: The possibilities of simplifying model geometry for CFD calculations have been described, the impact of CT image segmentation on geometric model accuracy and CFD simulation errors have been analysed, and recommendations for future research have been described. Conclusions: The measurement uncertainty of the nasal cavities’ walls has a significant impact on CFD simulations. The CFD simulations better approximate RMM results of patients after anemization, as the influence of the nasal mucosa on airflow is then reduced. A minor change in the geometry of the nasal cavities (within the range of reconstruction errors by CT image segmentation) has a major impact on the results of CFD simulations.

3

Reverse engineering technology in the process of automotive component innovation

Kender Štefan

Hutnik, Wiadomości Hutnicze

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2023

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Vol. 90, nr 3

16--23

EN

The paper presents the possibilities of using reverse engineering technology in the digitization of automotive components and their innovation. The selected car component was digitized. A CAD model of the part was created based on the scanned point clouds. Point clouds were scanned by a laser 3D scanner in PolyWorks software. The reference 3D model was created from a point cloud in CATIA V5. It is then possible to compare the scanned point cloud and the reference model. The comparison of the scanned point cloud and the reference model is performed in PolyWorks. The process of scanning an automotive component using the FARO PLATINUM ARM 3D scanning arm is documented. The reference 3D model was subsequently modified and innovated for the facelift car model.

PL

W artykule przedstawiono możliwości wykorzystania technologii inżynierii odwrotnej w digitalizacji podzespołów motoryzacyjnych oraz ich innowacyjności. Wybrany element samochodu został zdigitalizowany. Na podstawie zeskanowanych chmur punktów stworzono model CAD części. Chmury punktów skanowano laserowym skanerem 3D w programie PolyWorks. Referencyjny model 3D został stworzony z chmury punktów w programie CATIA V5. Możliwe jest wówczas porównanie zeskanowanej chmury punktów z modelem referencyjnym. Porównanie zeskanowanej chmury punktów z modelem referencyjnym odbywa się w programie PolyWorks. Udokumentowano proces skanowania komponentu samochodowego za pomocą ramienia skanującego FARO PLATINUM ARM 3D. Referencyjny model 3D został następnie zmodyfikowany i udoskonalony na potrzeby modelu samochodu po liftingu.

4

A way of supporting the servicing of production machines using reverse engineering and 3D printing techniques

Loska Andrzej, Palka Dorota, Bień Alicja, Substelny Katarzyna

Technologia i Automatyzacja Montażu

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2022

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nr 1

28--36

EN

The use of machines and devices causes their components to wear out, which leads to damage. The easiest and fastest method of repair is to replace this element with a new one. The problem arises when the desired element is not available on the market, technical documentation is unavailable or the costs of acquiring a new element are too high. In such a situation, engineering reconstruction, also known as reverse engineering, is used, which allows for the reconstruction of technical documentation and the production of a new product thanks to additive technology. The article presents the process of reverse engineering and the types of additive manufacturing technology. The aim of the article is to present the possibilities of using the reverse engineering method and 3D printing in the reconstruction of sample machine parts. The work uses the FDM (Fused Deposition Modeling) spatial production technology. The relevance of the article is confirmed by the possibility of its practical use in the field of machine servicing support.

PL

Eksploatacja maszyn i urządzeń powoduje, że ich podzespoły zużywają się, a to prowadzi do uszkodzeń. Najprostszą i najszybszą metodą naprawy jest wymiana tego elementu na nowy. Problem pojawia się, gdy pożądany element nie jest dostępny na rynku, niedostępna jest dokumentacja techniczna lub koszty pozyskania nowego elementu są zbyt wysokie. W takiej sytuacji zastosowanie znajduje rekonstrukcja inżynierska nazywana również inżynierią odwrotną, która pozwala na odtworzenie dokumentacji technicznej oraz wykonanie nowego produktu dzięki technologii addytywnej. W artykule przedstawiono proces przebiegu inżynierii odwrotnej oraz rodzaje technologii wytwarzania przyrostowego. Celem artykułu jest przedstawianie możliwości zastosowania metody inżynierii odwrotnej oraz druku przestrzennego w rekonstrukcji przykładowych części maszyn. W pracy wykorzystano technologię wytwarzania przestrzennego FDM (Fused Deposition Modeling). Zasadność artykułu potwierdza możliwość jego praktycznego wykorzystania w zakresie wspomagania serwisowania maszyn.

5

Methods of implementation and operation of hardware DRM protection on the example of printer cartridges

Cybowski Wojciech

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2022

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nr 25(1)

117--137

EN

Tens of millions of printers are sold each year, including copiers and multifunction devices. Each printer needs an ink or toner cartridge, depending on the type of printer. This is where the problems arise that anyone who owns such a device has encountered – the price and availability of cartridges. A set of original cartridges for the printer we bought can sometimes cost more than the printer itself. On the other hand, it is not always possible to buy cheaper replacement consumables. This is often due to the fact that the manufacturer of the printer has implemented a Digital Rights Management (DRM) protection in the chip connected to the cartridge. Bypassing such protection is not trivial, and when a way to do so is learned, it is not disclosed because of the commercial value of such knowledge. The goal of this paper is to determine if it is possible to find out for ourselves how selected DRM protections work by using reverse engineering, and to develop a way to reset these protections so that we are not tied to the price and availability of consumables on the market, as we can remanufacture our cartridges ourselves, which is especially important in the context of the Right to Repair.

6

Prototype of hand prosthesis components manufactured with biocompatible material using PolyJet Matrix technology

Szczygieł Paweł

Mechanik

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2022

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R. 95, nr 7

50--54

EN

This paper presents a procedure for developing a components of the hand prosthesis using reverse engineering. The hand model was obtained using a plaster cast and a 3D scanner. The 3D model of the prosthesis was remodelled using selected CAD software. The prosthesis was made of MED610 polymer material using PolyJet Matrix (PJM) technology. The MED610 material was chosen for its biocompatible properties. The printed model of the finger prosthesis was subjected to a bending test.

PL

W artykule przedstawiono procedurę projektowania elementów protezy dłoni z wykorzystaniem inżynierii odwrotnej. Modele dłoni odwzorowano w postaci odlewów gipsowych. Korzystając ze skanera 3D otrzymano chmurę punktów, którą przekonwertowano do pliku STL. Model 3D protezy przebudowano w oprogramowaniu CAD. Protezę wykonano z materiału polimerowego MED610 z zastosowaniem technologii PolyJet Matrix (PJM). Materiał MED610 został wybrany ze względu na biokompatybilne właściwości. Wydrukowany model protezy poddano próbie zginania.

7

Reverse engineering of research engine cylinder-head

Cieślik Wojciech, Szwajca Filip, Wisłocki Krzysztof

Combustion Engines

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2022

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R. 61, nr 2

73--82

EN

The pursuit of increasing the efficiency of internal combustion engines is an ongoing engineering task that requires numerous research efforts. New concepts of injection or combustion systems require preliminary investigation work using research engines. These engines, usually single-cylinder, make it possible to isolate a single variable in a complex combustion mixture preparation process, thus enabling analysis of the changes being made. However, these engines are relatively expensive and their designs are offered by a limited number of manufacturers. The authors of this paper have successfully undertaken the engineering task of modifying an existing research engine cylinder head in such a way as to implement an electronically controlled variable valve timing system of the intake system. The process of reverse engineering, together with design assumptions that finally contributed to the construction of the assumed solution has been described in this paper.

8

Specified weight cutting system for irregular solid material based on 3D scanning

He Jiadong, Huang Yafeng, Zang Xiao, Zhang Yajun

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

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Vol. 70, nr 5

art. no. e143108

EN

A specified weight-cutting system for irregular solid materials such as rubber is important for industrial engineering. Currently, the workers’ experience is used, which has low accuracy and efficiency. A specified weight cutting system for irregular solid material based on 3D scanning is proposed in this paper, which aims to overcome the inaccuracy and inefficiency of the manual cutting process. Firstly, the surface of the irregular solid material is scanned by a tracking 3D laser scanner, and a triangular mesh file is generated. Secondly, the defects of the 3D model are repaired by reverse engineering, and then the 3D model file of the irregular objects is generated. Finally, the cutting position of the specified weight solid material is calculated by the calculation algorithm in UG software. In short, this research creates a new method for processing data collected by the 3D scanner, by working jointly with multiple devices and software, facilitating the cutting of irregular solid materials with specified weights. Additionally, the system has the advantage of accuracy and efficiency over the experience of workers.

9

Reverse engineering in modeling agricultural products

Boryga Marek, Kołodziej Paweł

Agricultural Engineering

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2022

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Vol. 26, No. 1

105--117

EN

The purpose of the study was to use reverse engineering to model biological products, especially sugar beet root. In the process of creating the solid model, the appropriate tools available in the 3D design environment were applied. The 3D scan of the beet, in the form of a spatial point cloud, was used to project the root geometry. This was, in turn, used to construct a triangulation grid that includes nodal points of triangles. The subsequent steps presented the process of creating a solid model using the Interpolation Spline tool. Attention has been paid to the possibility of modifying the geometry by inserting additional points into the existing interpolation spline and changing angular position as well as the distance of the structural planes. Geometry mapping error values were determined with regard to the reference model depending on the spread value of the Structural Planes. Error courses are non-linear with a logarithmic line trend (surface field error) and a linear line trend (volume error). The effects demonstrated the usefulness of geometry projection and its applicability to support the strength testing of biological materials, with particular emphasis on dynamic tests using whole roots.

PL

Celem pracy było zastosowanie inżynierii odwrotnej do modelowania produktów pochodzenia biologicznego a w szególności korzenia buraka cukrowego. W procesie tworzenia modelu bryłowego wykorzystano odpowiednie narzędzia jakimi dysponuje środowisko do projektowania 3D. Pomocą w odwzorowaniu geometrii korzenia był trójwymiarowy skan buraka stanowiący przestrzenną chmurę punktów. Posłużyła ona do budowy siatki triangulacyjnej obejmującej punkty węzłowe trójkątów. W kolejnych krokach przedstawiono przebieg tworzenia modelu bryłowego za pomocą narzędzia Splajn interpolacyjny. Zwrócono uwagę na możliwości modyfikacji odtwarzania geometrii poprzez wprowadzanie kolejnych dodatkowych punktów do istniejącego Splajnu interpolacyjnego oraz zmiany położenia kątowego jak również odległości Płaszczyzn konstrukcyjnych. Wyznaczono wartości błędów odwzorowania geometrii w odniesieniu do modelu referencyjnego w zależności od wartości rozstawienia Płaszczyzn konstrukcyjnych. Przebiegi błędów mają charakter nieliniowy z logarytmiczną linią tredu - błąd pola powierzchni oraz z liniową linią tredu - błąd objętości. Na podstawie uzykanych efektów wykazano przydatność odtwarania geometrii i możliwość jej zastosowania do wspomagania badań wytrzymałościowych materiałów biologicznych ze szczególnym uwzględnieniem testów dynamicznych z wykorzystaniem całych korzeni.

10

Reverse engineering of parts with asymmetrical properties using replacement materials

Aladag Mehmet, Bernacka Monika, Joka-Yildiz Magdalena, Grodzki Wojciech, Zamojski Przemysław, Zgłobicka Izabela

Acta Mechanica et Automatica

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2022

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Vol. 16, no. 3

250--258

EN

Reverse engineering (RE) aims at the reproduction of products following a detailed examination of their construction or composition. Nowadays, industrial applications of RE were boosted by combining it with additive manufacturing. Printing of reverse-engineered elements has become an option particularly when spare parts are needed. In this paper, a case study was presented that explains how such an approach can be implemented in the case of products with asymmetric mechanical properties and using replacement materials. In this case study, a reverse engineering application was conducted on a textile machine spare part. To this end, the nearest material was selected to the actual material selection and some mechanical tests were made to validate it. Next, a replacement part was designed by following the asymmetric push-in pull-out characteristic. Finally, the finite element analysis with Additive Manufacturing was combined and validated experimentally.

11

Zastosowanie systemów komputerowo wspomagających projektowanie w procesach planowania zabiegów chirurgicznych w obrębie obszaru żuchwy

Turek Paweł, Skowron Natalia

Przegląd Mechaniczny

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2021

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nr 3

31--35

PL

W artykule przedstawiono obecne możliwości w zakresie projektowania oraz wytwarzania modeli struktur anatomicznych, szablonów chirurgicznych oraz implantów do planowania zabiegów chirurgicznych w obrębie obszaru żuchwy. W pierwszym etapie przedstawiono proces rekonstrukcji 3D geometrii żuchwy przy użyciu oprogramowania 3D-Slicer 4.8.1. Kolejny etap procesu polegał na cyfrowym odtworzeniu ciągłości geometrii żuchwy w miejscu wystąpienia złamania. Proces ten przeprowadzono w środowisku Meshmixer. Następnie zamodelowano geometrię płytek chirurgicznych w oprogramowaniu CATIA V5R20. Ostatni etap polegał na wykonaniu metodą przyrostową FDM modelu struktury anatomicznej żuchwy sprzed wystąpienia urazu oraz płytek chirurgicznych, które posłużyły do planowania zabiegu otworzenia ciągłości geometrii żuchwy w miejscu wystąpienia złamania.

EN

The article presents the current possibilities of designing and manufacturing models of anatomical structures, templates and implants for planning surgical procedures within the mandibular area. The first stage presented the process of 3D reconstruction of the mandible geometry using the 3D-Slicer 4.8.1 software. The next step in the process was to digitally reconstruct the continuity of the mandible geometry in the area of fracture. This process was performed in the Meshmixer software. Then, the geometry of the surgical plates was modeled in CATIA V5R20 software. The last stage presented manufacturing process of the anatomical structure of the mandible before the injury, and surgical plates using FDM technology. The final models were used to plan the procedure within the mandibular area.

12

Application of Selected Reverse Engineering Procedures Based on Specific Requirements

Hrčková Mária, Koleda Pavol

Multidisciplinary Aspects of Production Engineering

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2021

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Vol. 4, Iss. 1

75--85

EN

The paper describes a solution of reverse engineering tasks using the equipment of the laboratory of the Technical University in Zvolen. The first task was linked to evaluation of a wear rate of the tool used to for mulching and elimination of unwanted wood or weed vegetation. The obtained data will be used as a base line for determination of the time interval for the tool replacement. We developed a prototype of components and their drawing documentation for a single-purpose machine for cutting barley. We created the 3D model using the method of photogrammetry. The finished drawing documentation and prototypes were handed over to the company KRUP. Finally, we identified the most suitable procedures for creating a model of a part with a complex shape. We tested the techniques of editing the point cloud processing, as well as of smoothing the surfaces and automating the creation of partial geometric elements of the model. Based on the properties of the component, which is the starting point of the entire reverse engineering process and from the achieved results, we set recommendations for the selection of appropriate procedures.

13

Właściwości lekkich cegieł z 800-letniego obiektu zabytkowego w Indiach

Kumar Degloorkar Nikhil, Kumar Rathish Pancharathi

Cement Wapno Beton

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2021

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R. 26, nr 2

89--100

PL

Renowacja i konserwacja obiektów dziedzictwa kulturowego w każdym kraju jest zadaniem trudnym i czasami wymaga dużej uwagi. Jest to równocześnie ważne dla podtrzymania kultury i dziedzictwa społeczeństw. Jednak często bardzo trudno jest znaleźć odpowiednie materiały stosowane w przeszłości i dlatego w wyniku zastępowania ich dostępnymi spoiwami cementowymi, może dojść do uszkodzenia starych materiałów. Z tego powodu trzeba zbadać te antyczne materiały i opracować podobne zastępcze, o zbliżonych właściwościach. Ten materiał zastępczy powinien mieć podobny skład mineralny i właściwości fizyczne, a wówczas nie będzie stwarzał problemów w trakcie naprawy i po jej wykonaniu. W niniejszej pracy, przy użyciu nowoczesnych technik analitycznych, a przede wszystkim mikroskopii elektronowej, rentgenografii i spektroskopii w podczerwieni, zbadano skład antycznej cegły pływającej, stosowanej w indyjskim obiekcie zabytkowym. Określono również właściwości fizyczne, a mianowicie ciężar właściwy, gęstość nasypową, zawartość pustek i porowatość. Na podstawie przeprowadzonej analizy można stwierdzić, że cegły były lekkie, o czym decydowała duża porowatość, i mogły pływać w wodzie, gdyż były to pojedyncze pory zamknięte. Cegły wykonano z gliny prażonej w niskich temperaturach, co pozwoliło uzyskać dużą porowatość. Skład chemiczny cegieł, oznaczony pod mikroskopem elektronowym przy zastosowaniu mikroanalizy rentgenowskiej, składał się z kwarcu, tlenku glinu i hematytu. To niskotemperaturowe prażenie gliny zostało poparte analizą FTIR, wykazującą wiązania Si-O, które nie są trwałe w wysokiej temperaturze.

EN

Restoration and preservation of Heritage Structures in any country is a challenging task and sometimes requires urgent attention. Moreover, it is important for sustenance of culture and heritage of the society. But many times, it is very difficult to find matching materials used in the past and hence due to use of available cementitious materials there can be degeneration of existing material. In view of this, there is a need to characterize these ancient materials and develop alternate materials with almost similar characteristics. With this knowledge, an alternate material similar in mineral composition and physical properties need to be developed, which will not have compatibility issues during and after repair. In the present study, the material characterization of an ancient floating brick at an Indian Heritage site was examined using modern analytical techniques like SEM-EDS, XRD and FTIR. In addition, the physical properties like specific gravity, bulk density, voids ratio and porosity were also determined. From the analysis, it could be confirmed that the bricks were light in weight due to the pores content and could float in water due to the non-interconnected porosity. Also, the presence of quartz, alumina and hematite from SEM-EDS analysis confirmed that these bricks were made of firing the clay, at lower temperatures, to induce pores. This low temperature firing of clay was supported by FTIR analysis indicating the presence of Si-O bond that would have disappeared at higher temperature.

14

Resolution in the 3D modeling of objects for additive manufacturing and reverse engineering – shutter effect

Coutiño-Moreno Elvis, Estrada Quirino, Maldonado-Onofre Daniel, Rodriguez-Mendez Alejandro, Gomez-Giron Julio

Applied Computer Science

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2021

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Vol. 17, no 1

40--52

EN

This article presents a proportional relationship between Shutter and the value of the resolution scanning system that allows decision making for modeling 3D parts used in reverse engineering and additive manufacturing. As a first step, the object of interest is treated to dim excessive brightness, then the object is scanned (by point cloud or mesh) with the use of a Handyscan 700 scanner. The point cloud is processed with the Geomagic software Desing X to generate a CAD image and a “.stl” file for 3D printing.

15

Digital Shape and Geometric Dimension Analysis of Polymer Fuel Tanks

Józwik J., Dziedzic K.

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 4

38--48

EN

3D optical scanning method, is employed to digital shape and geometric dimension analysis of fuel tanks. The following paper presents the application possibilities of the optical 3D measurement method for measuring and archiving dimensions of geometrically complex parts, on the example of a passenger car fuel tank in local company. Based on the conducted measurements, for a specific type and size of the population of fuel tanks, proposed model that classifies the geometric accuracy of the tanks produced in the production line. For the analysis and data processing different informatics techniques have been used. The main objective of theirs was to identify the possibility of implementing the system for automation of the measurement to the production line. The measurements were implementation at local company - a manufacturer of polymer tanks in the automotive industry. For most of the measuring points, the mean value of the measuring deviations ranged from -1 mm to +1 mm. The mean values of the standard deviations are presented for a representative deviation of the X dimension of 0.1; 5; 10; 15 and 20 mm were respectively: 0.014; 0.150; 0.172; 0.289; 0.340 mm. The dimensional shape assessment of the manufactured tanks is extremely important from the point of view of the automation of this task in the production line. The optimization of the measurement of tanks carried out in laboratory conditions was implemented on the production line. The main task of optical scanning for the assessment of dimensional conformity has not been used so far in factory. This is due not only to the cost of such systems, but also to certain limitations that have been resolved thanks to laboratory tests. The obtained results of the metrological inspection make it possible to identify significant dimensional and shape deviations of automatically manufactured tanks. The proposed use of artificial neural networks allows the production with a high quality of tanks accuracy with the minimum the number of scanned tanks in the production line. The paper also presents the possibilities of the computer software to analyze the deviations of geometrically very complex parts.

16

The analysis of the gear’s geometry measurement with various measuring systems

Tymczyszyn Jarosław

Technologia i Automatyzacja Montażu

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2020

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nr 3

39--46

EN

The paper presents a comparison between contact and optical measuring systems, which can be implemented to measure the shape and dimensional accuracy. The comparison included the MarSurf XC20 contact system, the iNEXIVE optical microscope and the MCA II measuring arm with the MMDx100 laser head as well as the ATOS II Triple Scane structured light scanner. The measurements were conducted on a part of a gear rim. The assessment of the measuring accuracy in relation to the nominal model was performed in the GOM Inspect software. The parametric model of the gear created in the NX software was adopted as the nominal model. According to the obtained reports, it results that the MarSurf XC20 is the most accurate 2D measuring system whereas the ATOS II Triple Scane is the most accurate 3D measuring system.

PL

W artykule przedstawiono porównanie pomiarowych systemów; stykowych oraz optycznych, możliwych do wykorzystania przy weryfikacji dokładności wymiarowo-kształtowej. Porównanie obejmowało system stykowy MarSurf XC20, mikroskop optyczny iNEXIVE , ramię pomiarowe MCA II z głowicą laserową MMDx100 oraz skaner światła strukturalnego ATOS II Triple Scane. Pomiary przeprowadzono na fragmencie wieńca koła zębatego. Ocenę dokładności pomiaru w odniesieniu do modelu nominalnego przeprowadzono w programie GOM Inspect. Za model nominalny przyjęto model parametryczny koła zębatego stworzonego w systemie NX. Według otrzymanych raportów wynika, że najbardziej dokładnym systemem pomiarowym 2D jest MarSurf XC20, a systemem pomiarowym 3D ATOS II Triple Scane.

17

Geometry extraction from GCODE files destined for 3D printers

Kiński Wojciech, Sobieski Wojciech

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2020

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nr 23(2)

115--130

EN

The paper presents a method of conversion of GCODE files designed for additive manufacturing in 3D printers to a format which may be conveniently visualized. In the investigations three different 3D models were created: a) shell model (a casing); b) solid model (a gear); c) model with curvilinear elements (a screw). All these models were converted to GCODE files. Next the reverse engineering was applied and GCODE files were converted to points sets. These points represent particular locations of the print head. In the developed algorithm the linear interpolation was added to obtain intermediate points between locations of the print head for longer sections. The final part shows an attempt of applying Poisson Surface Reconstruction in order to obtain the original geometry. The main motivation to develop a new software resulted from the observation that sometimes the original solid model is no longer available, while there is a need to change some geometry details or settings before production stage.

18

Use of Reverse Engineering and Additive Printing in the Reconstruction of Gears

Palka Dorota

Multidisciplinary Aspects of Production Engineering

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2020

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Vol. 3, Iss. 1

274--284

EN

Despite the very rapid technological development, the general concept of mechanical devices has not changed. Still, the most common element of these devices are gears, whose range of use is very wide. There are both technological and historical considerations for the reconstruction of gears and other elements. In particular, this applies to spare parts for technical facilities that are not available on the market or service costs are too high. Contemporary reconstruction is called Reverse Engineering, which offers tools that allow transformation of an existing object through a virtual model into the final real product. Modern production engineering is based on innovative CAD – Computer Aided Designed design methods and computer-aided manufacturing technologies, CAM – Computer Aided Manufacturing. The rapid development of 3D CAD systems has led to the development of solutions to obtain the designed object, already at the development stage. Such a solution is the Rapid Prototyping method, designed for fast, precise and repeatable production of machine components. Widespread use and growing interest in the use of additive printing influenced the development of this technology. The purpose of the article is to present the practical application of the Reverse Engineering method and 3D printing in the reconstruction of gears. The object of research is the real gear, which has been reconstructed using Reverse Engineering and 3D printing. The article presents the basic assumptions of the methods used and the methodology for conducting reconstruction work. FDM (Fused Deposition Modeling) technology was used for the research. The results obtained are a real example of the practical application of the presented methods. At the same time, they create great opportunities for their wider use.

19

Making copies of religious culture relics using reverse engineering

Pieróg Bartosz, Filipowicz Krzysztof, Pajor Mirosław

Mechanik

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2020

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R. 93, nr 4

16--19

EN

Presented is the process of making copies of reliefs that are religious culture relics. Described is making of two replacements of exhibits from West Pomeranian churches. Priceless relics were made available courtesy of the National Museum in Szczecin that poses them in its collection. Sculptures were scanned using a contactless method with an industrial 3D scanner. Obtained data were used to develop technology and make copies using five-axis milling centre to achieve a satisfying reconstruction of details. Copies were made during realisation of a master project on Mechanics and Machines Making studies in Mechanical Engineering and Mechatronics department of the West Pomeranian University of Technology in Szczecin. Achieved effects were, on one hand, the copies and on the other hand, the enrichment of the didactic process with practical experience, necessary in technical studies.

PL

Opisano proces kopiowania płaskorzeźb będących zabytkami kultury sakralnej. Omówiono wykonanie dwóch zastępczych eksponatów pochodzących z kościołów z Pomorza Zachodniego. Bezcenne zabytki zostały udostępnione przez Muzeum Narodowe w Szczecinie, w którego zbiorach się znajdują. Rzeźby zeskanowano metodą bezdotykową z użyciem przemysłowego skanera 3D. Na podstawie uzyskanych danych opracowano technikę wykonania kopii na pięcioosiowym centrum frezarskim, które dawało gwarancję satysfakcjonującego odwzorowania szczegółów. Wykonanie kopii było elementem pracy dyplomowej na kierunku Mechanika i Budowa Maszyn na Wydziale Inżynierii Mechanicznej i Mechatroniki Zachodniopomorskiego Uniwersytetu Technologicznego w Szczecinie. Dzięki temu oprócz wykonania kopii eksponatów osiągnięto efekt w postaci wzbogacenia procesu dydaktycznego o niezbędne w toku studiów technicznych doświadczenia praktyczne.

20

The Study on Effects of Walking on the Thermal Properties of Clothing and Subjective Comfort

Špelić Ivana, Rogale Dubravko, Mihelić Bogdanić Alka

Autex Research Journal

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2020

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Vol. 20, no. 3

228--243

EN

Former studies done by other authors investigated the first- and second-layered air gaps beneath the clothing garments. None of the previous studies reported multidisciplinary clothing design testing approach linking both the objective measuring methods and subjective responses, while testing the thermal properties linked to a microclimatic volume formed between the layers of garments forming the ensemble. Neither was determined the limiting value of the microclimatic volume for outerwear garments, after which the thermal insulation will start to decrease due to convection. By taking the advantage of the precise three-dimensional (3D) body scanning technology and reverse engineering 3D CAD tool, the volume of the microclimatic air layers formed under outerwear garments was determined to study the impact of the ensemble’s microclimatic volume on the overall insulation value, measured by means of the thermal manikin. The jacket with the smaller microclimatic volume provided 5.2–13.5% less insulation than wider jackets, while the ensembles with tighter jackets showed 0.74–1.9% less insulation in static and 0.9–2.7% more insulation in dynamic conditions, thus proving that the limiting value of the microclimatic volume is greater than previously reported for three-layered ensembles. The effective thermal insulation value was reduced in average by 20.98–25.34% between standing and moving manikins. The thermal manikins are designed for steady-state measurements and do not work well under transient conditions, so three human subjects were employed as evaluators of the clothing thermal quality. In cooler climatic conditions, the measured physiological parameters and subjects’ grades pointed to discomfort while wearing ensembles with tighter jackets.