Wyniki wyszukiwania - BazTech

1

Influence of geometry of HUD optical system on screen luminance distribution

Muszyński Paweł, Kusznier Jacek, Kusznier Paweł

Przegląd Elektrotechniczny

|

2023

|

R. 99, nr 1

198--202

EN

HUD screens are an element that enables simultaneous observation of the environment and reading the information displayed on it. This allows for increased safety especially in the movement of vehicles. This paper will present an analysis of the luminance distribution on the screen as dependent on the geometry of the optical system and ambient lighting.

PL

Ekrany HUD to element umożliwiający jednoczesną obserwację otoczenia i odczytywanie wyświetlanych na nim informacji. Pozwala to na zwiększenie bezpieczeństwa zwłaszcza w ruchu pojazdów. W artykule zostanie przedstawiona analiza rozkładu luminancji na ekranie w zależności od geometrii układu optycznego i oświetlenia otoczenia.

2

Surface roughness of photoacrylic resin shapes obtained using PolyJet additive technology

Turek Paweł, Bazan Anna, Budzik Grzegorz, Przeszłowski Łukasz, Gapiński Bartosz

Polimery

|

2023

|

Vol. 68, nr 11-12

631--639

EN

The article presents the results of analyzing the surface roughness of samples manufactured using the PolyJet additive technology. Three types of photopolyacrylic resins were used in the production process of the test samples. The samples were measured using stylus and optical measurement methods. The presented research extends information on the surface roughness of resins used in the PolyJet 3D printing process. It is a starting point for further improvement of measurement procedures for polymer materials.

PL

Zbadano chropowatość powierzchni kształtek wykonanych z trzech rodzajów żywic foto poliakrylowych metodą przyrostową PolyJet. Stosowano stykową i optyczną metodę pomiarową. Przedstawione badania poszerzają wiedzę w zakresie chropowatości powierzchni żywic stosowanych w procesie druku metodą PolyJet oraz stanowią punkt wyjścia do dalszych badań dotyczących usprawniania procedur pomiarowych w odniesieniu do próbek wykonanych z materiałów polimerowych.

3

Combining the Technology of Long-Range Laser 3D Scanners and Structured Light Handheld 3D Scanners to Digitize Large-sized Objects

Lipowiecki Ignacy, Rządkowski Witold, Zapał Wojciech, Kowalik Michał

Advances in Science and Technology. Research Journal

|

2023

|

Vol. 17, no 3

196--205

EN

This paper presents a new method of merging the results obtained with long-range laser 3D scanners and structured light handheld 3D scanners to digitalize large-sized objects. An overview of the solutions in which these types of scanners are used was conducted and combined with the analysis of the studies related to the measurement accu- racy they offer. The focus was on the problems that may arise during the digitization of detailed large-sized objects. A reference test object was then selected, which not only included the fine details that needed to be represented but also met the size criterion. The object was scanned by two 3D scanners and the data was then compared in various aspects, such as resolution, accuracy, and the measurement procedure. Significant discrepancies in the results were identified. They related to the resolution and quality of results as well as accuracy, reaching more than 20 mm. Therefore, a method of combining the results was developed to collate the advantages of both devices and elimi- nate their disadvantages. In the end, the analysis of obtained results was repeated and the results were presented.

4

Comparative accuracy analysis of triangulated surface models of a fossil skull digitized with various optic devices

Garashchenko Yaroslav, Kogan Ilja, Rucki Mirosław

Metrology and Measurement Systems

|

2022

|

Vol. 29, nr 1

37--51

EN

Digital metrology was applied for evaluate 3D models of the unique skull of a fossil tetrapod, Madygenerpeton pustulatum, generated using various 3D digitization methods. The skull surface is covered by minute tubercles making it challenging for digitization with appropriate accuracy. Uniqueness and fragility of the specimen preclude the use of tactile measuring systems for creating a standardized reference model. To overcome this problem, comparative analysis of the triangulated models generated from the clouds of points obtained with seven different devices was conducted using the Geomagic Studio and Autodesk PowerShape CAD software. In the proposed approach, geometrically and dimensionally closest-fitting models underwent detailed statistical analysis between surface polygons in three steps. First, 3D models obtained from different scanning methods were compared with each other in couples. Next, statistical analysis of the differences between the coupled models was performed. Finally, a rating list of the models related to the required accuracy was prepared. The proposed approach is applicable to any other scanned object, especially in palaeontological applications, where each object is unique and exhibits individual features.

5

A Quick-and-Dirty Method for assessing the Risk of Negative Aeration Effects of Shock Absorbers equipped with Shim Sliding Base Valves

Czop Piotr, Gniłka Jacek

Computer Assisted Methods in Engineering and Science

|

2022

|

Vol. 29, no. 3

229--260

EN

This paper presents a quick-and-dirty method to assess the risk of negative aeration effects occurring in twin-tube hydraulic shock absorbers used in passenger cars at the early design stage. The method is intended to be implemented as an engineering calculation tool based on the computational fluid dynamics (CFD) two-dimensional (2D)/three-dimensional (3D) steady-state single-phase model. The CFD model was previously validated with the use of the particle image velocimetry (PIV) experiment. The negative aeration effect is a wellknown issue for automotive and railway shock absorbers manufacturers. It results in uncontrolled on-vehicle vibrations and the deteriorated shock absorber damping characteristic. The major aeration contributor in twin-tube hydraulic shock absorbers is the sliding shim intake valve, which requires design optimization to avoid a negative aeration effect. The method validation was conducted with the customized test rig equipped with a transparent cylinder where the specific sliding intake valve was assembled. The proposed method also requires a lumped-parameter model of a twin-tube shock absorber, which allows to simulate boundary conditions in assessing particular reservoirs of a shock absorber, i.e., pressures and flow balance. The method is implemented as a calculation routine that converts CFD pressure regions into a gas concentration indicator (GCI) using the pressure-density characteristic of an oil-gas emulsion of a shock absorber. GCI is calculated based on the sum of particular 2D/3D grid elements. The method application is to minimize the risk of occurrence of negative aeration effects by avoiding expensive and time-consuming experimental tests. This method can also be used for in-production shock absorbers projects as a part of a continuous improvement cycle or in the case of inefficient shock absorbers claimed by a vehicle manufacturer. The application scope of the method can be extended for arbitrary twin-tube designs of shock absorbers in the automotive and railway industries.

6

Metrological analysis of additively manufactured copies of a fossil skull

Rucki Mirosław, Garashchenko Yaroslav, Kogan Ilja, Ryba Tomasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2022

|

Vol. 70, nr 6

art. no. e143827

EN

This paper presents the results of a metrological analysis of the additively manufactured (AM) copies of a complex geometrical object, namely the fossil skull of Madygenerpeton pustulatum. This fossil represents the unique remains of an extinct “reptiliomorph amphibian” of high importance for palaeontological science. For this research, the surface was scanned and twelve different copies were 3D-printed using various devices, materials, and AM techniques. The same digitized model was used as a reference to compare with the surfaces obtained by Mitutoyo Coordinate Measuring Machine (CMM) CRYSTA-Apex S 9166 for each copy. The fidelity of the copies was assessed through statistical analysis of the distances between compared surfaces. The methodology provided a good background for the choice of the most accurate copies and the elimination of the less accurate ones. The proposed approach can be applied to any object of complex geometry when reproduction accuracy is to be assessed.

7

Accuracy of the New Method of Alignment of Workpiece Using Structural-Light 3D Scanner

Gessner Andrzej, Ptaszyński Wojciech, Adam Waldemar

Advances in Science and Technology. Research Journal

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2022

|

Vol. 16, no 1

1--14

EN

This paper presents a new method of aligning workpieces for machining by means of optical measurements followed by the results of verification tests of this method. The overview of modern assessment methods of irregularly shaped blanks are discussed in this study, with particular emphasis on cast iron castings, as well as on problems related to their positioning and fixing for machining. A flowchart of the proposed method and its verification results in industrial conditions are also presented. The essence of the method is based on the comparison of two spatial models: a designed workpiece model and the actual model of a casting produced with a coordinate measuring technique. A series of six iron castings were tested. The obtained results indicate that the errors caused by locating amounted to a maximum of 2 mm (average 0.5 mm) and were three times lower than actual machining allowances. This points to the correctness of the developed method and the great potential for its industrial application. Additionally, a method for improving locating accuracy by modifying the shape of the retaining pin is presented.

8

Real-time camera pose estimation based on volleyball court view

Szelag K., Kurowski P., Bolewicki P., Sitnik R.

Opto-Electronics Review

|

2019

|

Vol. 27, No. 2

202--212

EN

The use of technology in sports has increased in recent years. One of the most influential of these technologies is referee support systems. Team sports such as volleyball require accurate and robust tracking systems that do not affect either the players or the court. This paper introduces the application of intrinsic and extrinsic camera calibration in a 12-camera volleyball referee system. Intrinsic parameters are calculated by using the classic pinhole model and Zhang’s method. To perform extrinsic calibration in real time, the volleyball court is treated as a global calibration artifact. Calibration keypoints are defined as court-line intersections. In addition, a new keypoint detection algorithm is proposed. It enables achievement of an accurate camera pose in regard to the court. With all 12 cameras calibrated in a common coordinate system, a dynamic camera stereo pair creation is possible. Therefore, with known ball 2D image coordinates, the 3D real ball coordinates can be reconstructed and the ball trajectory can be estimated. The performance of the proposed method is tested on a synthetic data set, including 3Ds Max rendering and real data scenarios. The mean camera pose error calculated for data biased with keypoint detection errors is approximately equal to 0.013% of the measurement volume. For the real data experiment with a human hand phantom, it is possible to determine the presence of the human phantom on the basis of the ball reflection attitude.

9

Metrological requirements for measurements of circadian radiation

Jakubowski P., Fryc I.

Optica Applicata

|

2018

|

Vol. 48, nr 4

697--704

EN

The article presents a definition of circadian radiation and its influence on human beings. Typical sources of this radiation have been discussed and compared. As the availability of devices designed for circadian radiation measurement is very limited, and their quality is rather poor, there is a need for the development of a new meter which would deliver precise data. The paper presents available methods of optical radiation measurement which can be used in a circadian radiation assessment. Advantages and disadvantages of presented methods have been discussed. A light path in typical measurement instruments has been analyzed, as well as the impact of each component on the final result (i.e. the influence of spatial correction, optical filters and detectors). Original results of authors’ research have been presented and the concept for decreasing the measurement error has been proposed.

10

Optyczna metoda pomiaru odkształceń stalowych belek teowych podczas gięcia na zimno

Marcinczak K., Lorenc W., Rowiński S., Kożuch M.

Materiały Budowlane

|

2018

|

nr 4

105--106

PL

W artykule omówiono optyczną metodę pomiaru odkształceń DIC (Digital Image Correlation). Zastosowano ją do pomiaru odkształceń stalowych belek teowych poddanych gięciu na zimno. Odwzorowano proces nadawania podniesienia wykonawczego w stalowych belkach mostowych z wyciętym środnikiem o kształcie linii MCL. Otrzymane rezultaty badań doświadczalnych porównano z wynikami analiz numerycznych.

EN

The paper presents non-contact optical technique for measuring strains DIC (Digital Image Correlation). The method was used to measured cold strains of steel T-beams during cold bending. The process of cambering of bridge beams with steel shape MCL dowel was simulated. The obtained results were compared to numerical analysis.

11

Wyznaczanie objętości wyrzutowej pneumatycznej pompy wspomagania serca siecią neuronową i transformatą falkową

Grad L., Sulej W., Murawski K.

Przegląd Teleinformatyczny

|

2017

|

T. 5, Nr 4 (45)

53--65

PL

W artykule przedstawiono wyniki uzyskane w trakcie badań będących kontynuacją prac nad wykorzystaniem sztucznych sieci neuronowych do określania relacji między widokiem membrany wiotkiej i objętością wyrzutową komory krwi mechanicznej, pozaustrojowej pompy wspomagania serca. Celem pracy było zbadanie możliwości zwiększenia dokładności obliczeń podczas wyznaczania objętości wyrzutowej przez sztuczną sieć neuronową. Badania koncentrowały się na technice ekstrakcji cech z obrazu. W ich trakcie użyto transformatę falkową. Otrzymane wyniki porównano z wynikami uzyskanymi uprzednio przez inne metody. Badania przeprowadzono na modelu pompy wspomagania serca, który był używany także w poprzednich doświadczeniach.

EN

The paper presents results obtained during research, which are the continuation of work on the use of artificial neural networks to determine the relationship between the view of membrane and the stroke volume of the blood chamber of the mechanical pneumatic prosthetic heart. The purpose of the research was to increase the accuracy of determination the stroke volume of the blood chamber. Therefore, the study was focused on the technique of the features extraction from the image. Received results were compared to the results obtained previously using other methods. Tests were conducted on the same model of mechanical prosthetic heart, which have been used in previous experiments.

12

Ocena dokładności geometrii powierzchni bocznej zębów koła zębatego wykonanego addytywną metodą SLS

Budzik G., Dziubek T., Sobolewski B.

Przegląd Mechaniczny

|

2017

|

nr 10

50--53

PL

W artykule zaprezentowano zagadnienia oraz wyniki prac związane z określeniem dokładności geometrii powierzchni bocznej zębów walcowego koła zębatego, wytworzonego z zastosowaniem przyrostowej techniki SLS (ang. Selective Laser Sintering). Przedstawione wyniki badań dotyczą prototypu zębnika, którego geometrię zamodelowano z zastosowaniem metody symulacji obróbki w środowisku oprogramowania Autodesk Inventor. Model fizyczny poddano procesowi pomiarowemu przeprowadzonemu z użyciem optycznego skanera 3D Atos II Triple Scan. Na podstawie otrzymanych danych pomiarowych przeprowadzono analizy dokładności otrzymanej geometrii, wykonane w odniesieniu do nominalnego modelu 3D-CAD. Analizie poddane zostało koło przed procesem piaskowania.

EN

The paper presents the issues and results of the work on determining the geometry accuracy of the teeth side surface of cilindrical gear manufactured using the Selective Laser Sintering (SLS) technique. The results of this study refer to a pinion prototype whose geometry has been modeled using the machining simulation method in an Autodesk Inventor software environment. The physical model was subjected to a measuring process carried out using the Atos II Triple Scan Optical Scanner. The accuracy analysis of the obtained geometry were performed on the basis of the received measurement data in refers to the nominal 3D-CAD model. The analysis was done before the sandblasting process.

13

Triangulation methods for effusion holes measurements in combustion chambers of aircraft engines

Lampa P., Mrzygłód M., Reiner J.

Mechanik

|

2017

|

R. 90, nr 12

1164--1168

PL

Ważnym problemem dotyczącym konstrukcji nowoczesnych turboodrzutowych silników lotniczych jest efektywne chłodzenie komór spalania, realizowane poprzez otwory efuzyjne. Kanały takie, drążone laserowo, stanowią jednak poważne wyzwanie metrologiczne ze względu na niewielką średnicę (poniżej 1 mm), nieregularny kształt i kątową orientację względem powierzchni. Pomiary metodami kontaktowymi CMM są więc czasochłonne, obarczone znaczną niepewnością pomiaru oraz ryzykiem uszkodzenia trzpienia pomiarowego. W artykule porównano dwie metody skanowania triangulacyjnego powierzchni komory spalania silnika z kątowymi otworami efuzyjnymi (w kierunku normalnym do powierzchni oraz współosiowo z otworem). Ponadto oceniono cztery opracowane algorytmy przetwarzania danych pomiarowych, których celem jest wyznaczenie położenia i średnicy otworów. Wskazano na problem zakłóceń dotyczących pomiaru i przetwarzania danych.

EN

An important problem of modern aero-engines’ construction is effective cooling of combustor liner attained by effusion holes. The laser-drilled channels are a critical metrological challenge resulting from their small diameter (below 1 mm), irregular shape and angular orientation to the surface. Hence, in this case, the tactile CMM measurement methods are timeconsuming, error-susceptible and hazardous to the measuring stylus. The paper compares two methods of triangulation scanning of the surface of the engine combustion chamber with angular effusion holes (according to normal to surface and coaxially with hole). Additionally, four algorithms for processing measurement data were developed and evaluated, aiming at determination of the position and holes diameter. The paper also discusses the problem of measurement and calculation disturbance.

14

Pomiar dokładności kształtu pióra łopatki wirnika ramieniem pomiarowym

Burek J., Turek P., Gdula M.

Mechanik

|

2016

|

R. 89, nr 11

1642--1643

PL

Przedstawiono wyniki badań dokładności pomiaru kształtu pióra łopatki wirnika ramieniem pomiarowym wyposażonym w głowicę laserową. Wyniki pomiarów zostały porównane z teoretycznym modelem CAD w programie GOM Inspect.

EN

The paper presents comparative study of analysis the accuracy of geometry rotor blade. Measurements was preformed using coordinate measuring arm with optical system. The results of measurements was compared with the theoretical CAD model in GOM Inspect software.

15

Methodology of increasing accuracy of gear models manufactured using additive FDM method

Budzik G., Dziubek T., Kozik B., Sobolewski B.

Advances in Manufacturing Science and Technology

|

2015

|

Vol. 39, nr 4

37--52

EN

The paper presents methodology of increasing the accuracy of models of gears made applying additive methods. As a part of activities related to this subject, it was necessary to develop 3D-CAD research gears, which were the basis for producing physical models made using incremental FDM manufacturing technology. The created models were verified in order to determine the accuracy of resulting geometry. Then modifications were introduced to models so as to increase their accuracy. On this basis, in an iterative process, compensation coefficients were calculated to ensure reduction of defects in geometry with respect to a nominal 3D-CAD model.

PL

W artykule przedstawiono sposób poprawy dokładności modeli kół zębatych wytwarzanych z zastosowaniem metod addytywnych. Opracowano model 3D-CAD badawczych kół zębatych. Stanowiły podstawę do wytworzenia modeli fizycznych wykonywanych z zastosowaniem przyrostowej techniki wytwarzania FDM. Modele poddano weryfikacji w celu określenia dokładności ich wykonania. Wprowadzono modyfikację tych modeli dla podwyższenia ich dokładności. W procesie iteracyjnym ustalono wartości współczynnika kompensacji odkształceń. Zapewniono zmniejszenie błędów wykonania modelu w porównaniu z nominalnym modelem 3D-CAD.

16

Innowacje w technologii obróbki korpusów żeliwnych

Adam W., Gessner A.

Przegląd Mechaniczny

|

2014

|

nr 10

41--45

PL

W publikacji przedstawiono metodę szybkiej oceny dokładności wykonania korpusów odlewanych z wykorzystaniem bezdotykowego skanera optycznego, a także propozycję metody ustawienia korpusu w przestrzeni obróbczej wykorzystującej wyniki pomiaru geometrii korpusu. Obie metody zostały zweryfikowane w warunkach przemysłowych.

EN

The paper presents a method of rapid evaluation of geometric accuracy of cast iron bodies with the use of optical scanner as well as a concept of cast iron body orienting within the machine tool space. Both methods were verified in the machine tool industry.

17

Analiza porównawcza badań pól powierzchni przekrojów

Kowaluk T., Ratajczak E.

Przegląd Elektrotechniczny

|

2014

|

R. 90, nr 8

216-219

PL

Celem pracy było porównanie pól powierzchni trzech różnych elementów za pomocą dwóch maszyn: tomografu komputerowego Metrotom 800 oraz maszyny optycznej OGP Zip. We wszystkich przypadkach zauważono istotny wpływ kroku próbkowania na wyniki największy wpływ podczas pomiaru elementów krzywoliniowych. Przeprowadzona analiza MANOVA wykazała ponadto, że istnieją istotne różnice w wynikach pomiarów uzyskanych na obu maszynach pomiarowych.

EN

The aim of the study was to compare the surface areas of three different elements using two machines: com-puter tomograph Metrotom 800 and optical machine OGP Zip. In all cases, significant influence of the sampling step on the results was noted. The greatest impact was noticed when measuring the curvilinear elements. The MANOVA analysis also revealed that there are significant differences in the results of measurements obtained from both measuring machines.

18

Badania wad head checking w szynach kolejowych metodą optyczną

Lesiak P., Wlazło M.

Prace Naukowe Politechniki Warszawskiej. Transport

|

2014

|

z. 104

33--42

PL

W artykule przedstawiono wyniki precyzyjnych pomiarów próbek szyn z wadami head checking (HC) optyczną metodą interferometrii CCI (ang. Coherence Correlation Interferometry). Zaprezentowano obiekt badań i uzasadniono potrzebę jego pomiarów. Omówiono zasadę pomiaru i parametry systemu badawczego opartego na profilometrze Talysurf CCI Lite firmy Taylor-Hobson. Dokonano pomiarów geometrycznych wycinków szyn z wadami HC o różnych parametrach oraz zarejestrowano ich obrazy 2D i 3D na tle tekstury powierzchni tocznej szyny. Wzbogacono wiedzę z otoczenia tych wad, wyznaczając miary podobieństwa ich obrazów z obrazami wzorców wad.

EN

The paper presents measurement results of head checking flaws occurring in the railway rail. The measurement was carried out by Coherence Correlation Interferometry (CCI). Research object and justification for measurement of its parameters were presented. The principle of operation and parameters for Talysurf CCI Lite Taylor-Hobson surface topography measuring device were given. The measurements of head checking flaws of different parameters and their 2D and 3D images were also presented. Calculation of similarity measure among head checking flaws and their patterns allowed for an enrichment of the research.

19

Porównanie wyników pomiaru deformacji próbki tensometrami elektrooporowymi i metodą fotogrametryczną

Nowakowski A., Sobczyk J., Nurkowski J., Gawor M., Lizak Z., Bujalski M.

Prace Instytutu Mechaniki Górotworu PAN

|

2013

|

Vol. 15, no. 1-2

95--109

PL

Praca poświecona jest zastosowaniu nowoczesnych optycznych technik pomiarowych do analizy stanu deformacji próbki podczas testu jednoosiowego ściskania. W ramach badań wykonano serie testów jednoosiowego ściskania na próbkach prostopadłościennych, podczas których wyznaczano odkształcenia lokalne i globalne badanej próbki z zastosowaniem metod tradycyjnych (tensometry elektrooporowe, indukcyjne czujniki przemieszczeń) oraz metody fotogrametrycznej bazującej na analizie wykonanych podczas eksperymentu zdjęć próbki. Badania wykazały, iż możliwym jest uzyskanie dobrej zgodności wyników pomiarów odkształceń lokalnych prowadzonych tensometrem elektrooporowym i metodą fotogrametryczną oraz duże rozbieżności wyniku pomiarów globalnych prowadzonych czujnikiem indukcyjnym i metoda fotogrametryczną. Przedyskutowano możliwe przyczyny zaistniałego stanu rzeczy i wskazania dla ewentualnych przyszłych badań.

EN

The work is devoted to the application of modern optical measurement techniques for the analysis of the deformation of the sample during uniaxial compression test. In the study a series of uniaxial compression tests on rectangular rock specimens was made. During the tests the local and global deformation of the sample were measured using traditional methods (strain gauges, inductive displacement sensors) and photogrammetric method based on the analysis of samples’ images taken during the experiments. Studies have shown that it is possible to obtain a good agreement between the results of local strain measurements conducted by strain gauges and photogrammetric method and large discrepancies between results of global measurements conducted by an inductive sensor and photogrammetric method. The possible causes of a given set of things were discussed as well as some indications for possible future research were formulated.

20

A novel, spherical shaped sun tracker

Wajss P., Filipowicz M.

Polska Energetyka Słoneczna

|

2013

|

nr 1-4

33--38

EN

A novel, spherical shaped sun tracker, capable of shifting the centre of gravity, has been built at the Faculty of Energy and Fuels at AGH-UST. First tilting tests were executed and the results of these measurements have been presented herein. To introduce the reader to the authors' concept of sun tracking, a revive of the recent literature concerning tracking has been mechanisms has been conducted and some interesting ideas as well operating prototypes have been described.