Wyniki wyszukiwania - BazTech

1

Model-based design approach to reducing mechanical vibrations

Czop P., Wszołek G.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 60, nr 1

39--47

EN

Purpose: The paper presents a sensitivity analysis method based on a first-principle model in order to reduce mechanical vibrations of a hydraulic damper. Design/methodology/approach: The first-principle model is formulated using a system of continuous ordinary differential equations capturing usually nonlinear relations among variables of the hydraulic damper model. The model applies three categories of parameters: geometrical, physical and phenomenological. Geometrical and physical parameters are deduced from construction and operational documentation. The phenomenological parameters are the adjustable ones, which are estimated or adjusted based on their roughly known values, e.g. friction/damping coefficients. Findings: The sensitivity analysis method provides major contributors and their magnitude that cause vibrations Research limitations/implications: The method accuracy is limited by the model accuracy and inherited nonlinear effects. Practical implications: The proposed model-based sensitivity method can be used to optimize prototypes of hydraulic dampers. Originality/value: The proposed sensitivity-analysis method minimizes a risk that a hydraulic damper does not meet the customer specification.

2

Slitting criterion for various rolling speeds in MSR rolling process

Stefanik A.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 27, nr 1

91-94

EN

Purpose: The main idea of MSR technology is the capability of producing two, three, four and even five rods simultaneously from a single strip in a hot rolling process. Correctly separation of the joined strips is the one of the mainly problem in MSR process. Changing the rolling speed may causes easier of the strand division. In this paper results of the computer simulation of the double slitting rolling process were presented. Design/methodology/approach: For numerical modelling of the multi rolling process a computer program Forge 2005, based by the finished element method was used. As a slitting criterion normalised Cockroft-Latham criterion was used. Findings: For the analysis performed in this study, it was found that increasing of the rolling speed causes of increasing the normalized Cockroft-Latham criterion. For the small values of rolling velocity the strip separation was easier. Research limitations/implications: Multi Slit Rolling process is applied in ribbed rods rolling. Adjusting of the rolling speed in multi slit rolling process could improve of the slitting band to the separated strips. Originality/value: Incorrect construction or bad gap matching could cause lack of separation propelled slitting rolls. The separation of the band is effected by means of separating rollers, which shape must be properly designed to suit to the slitting pass. Changing of the rolling speed could improve of the separation to the single strips.

3

Model of urban public transport network for the analysis of punctuality

Sobota A., Żochowska R.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 28, nr 1

63-66

EN

Purpose: The building of mathematic model, which enable description of urban public transport network is a purpose of the article. This model will make the estimation of public transport quality according to analysis of punctuality easier. Design/methodology/approach: The methodology of building the mathematical model of public transport network consists in application of the graph theory. The mathematical instruments make the description of real network easier. Findings: The mathematical model of public transport network on the proper level of aggregation may be effective instrument, which assists the decision process. It makes an estimation of chosen coefficients that describe public transport quality easier. Research limitations/implications: The research has been conducted only in the range of punctuality estimation for the sake of time-consuming and expenses. This limit also concerns database. It requires detailed description of public transport network to exact presentation in mathematic model. Originality/value: To make the calculations more efficient, the relative database has been built. It includes geometric parameters of the sections and junctions in network. It also covers all necessary detailed data of analysed public transport lines. The database is the ground for estimating punctuality in research area.

4

Constructional similarity in process of ordered construction families creating

Gendarz P., Chyra P., Rząsiński R.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 29, nr 1

53-56

EN

Purpose: The main reason for starting research concerning theory of constructional similarity was need to substitute traditional method of creating ordered families by new algorithmic methods orientated on computer aiding. Design/methodology/approach: The following paper treats about development and putting into practice rules of theory of constructional similarity as a main method realizing γ assignation (which determines relations between parameters of the future technical feature and its design features). Findings: The main achievements presented in this paper are developed theory of constructional similarity orientated on computer aiding, and used in designing process of new technical features. Moreover, method is highly susceptible to parameterization. Research limitations/implications: Analyzed methods develop algorithmisation of designing environment and support integration with the process of preparing the production. Intense research on the theory of technological similarity is being made nowadays. Practical implications: Described methods were being developed on practical examples of creating the module systems of hydraulic cylinders used in mining, slag cars used in metallurgy and gears series of types. Nowadays the gripping devices series of types is being made. Originality/value: Presented in the paper method of construction similarity is basis of selection of design features in the process of ordered construction families (series of types and module systems of constructions) creating. Presented method supports intensive development of the types of technical features and affects their competitiveness on the ready market.

5

Investigation and implantation of endoprosthesis in biological experiment on animals

Žitňanský M., Čaplovič L'., Rehák L'., Makai F.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 1

146-152

EN

Purpose: Purpose of this paper is to inform professional public about our research activities and results in the area of development of implants. Design/methodology/approach: Method used in the present study, was the computer design of 3D virtual model, rapid milling, rapid turning and special testing, to produce a new total endo-prosthesis for dogs. Findings: Results of these activities are eight complete total endo-prostheses for dog implantation and for test preparing in vitro and in vivo and finally, for biological experiments on animals - dogs. Research limitations/implications: This paper is the result of partly primary and partly applied research. The achieved results will be used for preparing of the total endo-prostheses into the human skeleton.

6

Introduction to use virtual reality visualisations in the exploitation and virtual testing of machines

Foit K.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 25, nr 2

57-60

EN

Purpose: Purpose of this paper: Due to quick evolution of virtual reality systems, this technology is more often used in processes of prototype's design. On the other hand it could be also effective in others applications like virtual manuals, help systems, catalogues, education, visualisation, testing and virtual prototyping. The aim of this paper is to show some properties of the selected virtual reality systems, which could be used in the exploitation and virtual tests of machines. Design/methodology/approach: All software tests have been provided on Windows platform using selected ActiveX plugins for browsers. Findings: Creation of presentations, virtual manuals or catalogues is not a difficult task. It can be done using widely available software. However, virtual prototyping and testing are harder to manage and requires more knowledge about computer simulation. EON/EonX and Cortona software are rather presentation than simulation tools, but there is still possibility to create interaction with other application or external hardware. Research limitations/implications: In described tests only selected software have been used. All results and conclusions are related to EON/EonX and Cortona applications. Practical implications: The use of ActiveX technology gives a possibility to use a ActiveX control in almost any modern Windows application that supports it. Windows platform is also often used in handheld devices and industrial applications, so it is possible to create a virtual manual or a presentation, which could be displayed directly on machine interface. Originality/value: VR technology is worldwide used in many areas. EON software creates new possibilities in the field of virtual reality by handling special interfaces and display features. In the paper it is shown that the software can be used for more conventional purposes, like creation of virtual manuals or interactive 3D presentation.

7

Identification of scanning errors using touch trigger probe head

Sokovic M., Cedilnik M., Kopac J.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

383-386

EN

Purpose: Creation of a mathematical model, which combine ball tip radius error and small tilt of the stylus to determine translational motion (in two directions) of the stylus ball centre, due to the surface slope. Design/methodology/approach: First error is described on two dimensional model, thus is very simple. Second model is based on 3D-mathematical model, which is a basis to determine (and plot) translational movement of the stylus ball according to surface slope. Findings: Accurate scanning process on freeform surface with touch trigger probe head could not be performed, due to number of reasons connected to the stylus ball and trigger probe head errors. Research limitations/implications: According to nature of this problem, 4D, 5D and 6D-graphs could not be plotted, which would define translational motion of the stylus ball centre at any slope surface. Practical implications: Understanding the physical model for described error is a basis to create mathematical compensation error model. Originality/value: No such mathematical model to determine translational motion (in two directions) of the stylus ball centre was published in any paper before.

8

Diskrete-continuum methods application for rotating machine-absorber interaction analysis

Stocko Z., Diveyev B., Topilnyckyj V.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

387-390

EN

Purpose: The main aim of this paper is improved dynamic vibration absorbers design with taking into accout complex rotating machines dynamic. Design/methodology/approach: The numerical schemes row is considered for the complex vibroexitated constructions. Methods of decomposition and the numerical schemes synthesis are considered on the basis of new methods of modal synthesis. Findings: Development of mathematical models of complicated machines and buildings in view of their interaction with system of dynamic vibration absorbers. Dynamic vibration absorbers - complicated rotating machines system design optimized on vibro- absorption properties. Research limitations/implications: The research must be done for non-linear rotor dynamics. Practical implications: The absorbers designed in accordance with this paper can be applied not only to electric machines or aeronautic structures, but to any other type of vibro-exitated structure, such as cars, chisel installation, optical, magneto-optical disks, washing machine, refrigerator, vacuum cleaner, etc. Originality/value: The paper has novelty both in theoretical, and in practical aspect. In order that optimal parameters of DVA be determinate the complete modeling of dynamics of rotating machine should be made. Traditional design methodology, based on discontinuous models of structures and machines are not effective for high frequency vibration.

9

Znaczenie twórczości w projektowaniu technicznym

Wrona R.

Archiwum Odlewnictwa

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2004

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R. 4, nr 14

582-592

PL

Twórczość i wiedza to pojęcia, które coraz częściej pojawiaja się w badaniach naukowych dotyczących projektowania. Sa potwierdzeniem, że dostrzega sie rolę twórczości jako źródła nowoczesnego rozwiązywania zadań projektowych. W artykule przedstawiono mechanizn=my myślenia twórczego oraz metodykę kształcenia projektantów. szczególną uwagę zwrócono na znaczenie informacji i metod służących rozwojowi twórczości.

EN

Creativeness and knowledge are the conceptions that appear in scientific research of the planning theory more and more often. It proves that one can see the consequence ofthe creativeness as a source of a modern way of solving of the planning tasks. The mechanisms of the creative thinking and methods of designers education were presented in this articIe. A special attention was paid to the meaning of information and methods of the creativeness development.

10

Znaczenie projektotwórcze informacji eksploatacyjnej dla konstruowania urządzeń dla osób niepełnosprawnych

Branowski B.

Zeszyty Naukowe Politechniki Białostockiej. Budowa i Eksploatacja Maszyn

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2001

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Z. 8

27-41

PL

W pracy przedstawiono koncepcje metodyczne wspomagania procesu projektowania obiektów technicznych dla osób niepełnosprawnych informacją eksploatacyjną. Dzięki strukturyzacji fazy eksploatacji na fazy częściowe ukazano znaczny potencjał projektowy. Pokazano dwie koncepcje scenariuszy procesów projektowania dla konstrukcji dopasowanych / wielowariantowych i konstrukcji nowych, wykorzystujące informację eksploatacyjną. Podano także przykłady wykorzystania analizy FMEA przyczyn i skutków wad określonego wózka inwalidzkiego w celu optymalizacji bezpieczeństwa eksploatacji oraz przeprojektowania konstrukcji.

EN

The methodical conceptions to support designing technical subjects for handicapped people, trough operation's information are presented in this paper. There has been shown designing potential due to structurisation operation on partly phases. Author described two conceptions of designing: for match constructions / a lot of variants and new constructions, using operation's information. The analyse FMEA determining causes and results invalid's truck defects also is presented. The aim is optimisation of security of operation and redesigning construction.

11

Komputery i oprogramowanie stosowane w projektowaniu technicznym

Lasota A.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2000

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z. 61

199-204

PL

W pracy przedstawiono wybrane wyniki dotyczące wykorzystania komputerów i oprogramowania w projektowaniu technicznym przez projektantów oraz konstruktorów. Rezultaty oparte są o przeprowadzone (pilotażowe) badania własne dotyczące zakresu i sposobu stosowania komputerów przez projektantów, konstruktorów maszyn i urządzeń oraz wykorzystania wiedzy o człowieku w projektowaniu technicznym.

EN

In this report were presented the selected results of computers and software use in technical design by designers and constructors. The results are based on pilot own reserches concerning: The range and way of computer use by designers, constructors, of machines and appliences and the use of the knowledge about the human in the technical design process.

12

Nowa procedura projektowania inżynierskiego z zakresu doboru materiałów i technologii uszlachetniania

Gawroński Z.

Inżynieria Materiałowa

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2000

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R. XXI, nr 3

108-114

PL

Zbadano wpływ azotowania próżniowego metodą NITROVAC na stan naprężeń własnych w warstwach wierzchnich stali SW7M. Stworzono bazę danych dotyczącą rozkładów naprężeń własnych w warstwie wierzchniej na podstawie metody Waismana-Philipsa. Na przykładzie mechanizmu krzywkowego rozdzielaczowej pompy DPA opracowano model numeryczny dla superponowania naprężeń własnych i pochodzących od obciążeń zewnętrznych. Symulację przeprowadzono Metodą Elementów Skończonych (MES) przy wykorzystaniu standardowego pakietu ANSYS 5.4. Na podstawie analizy widma naprężeń rzeczywistych w warunkach eksploatacji określono kryteria występowania poszczególnych (normalnych i patologicznych) postaci zużycia o charakterze zmęczenia stykowego. Wyniki modelowania zweryfikowano opierając się na obserwacji nadzorowanej seryjnych pomp wtryskowych na stacji prób oraz pomp zdemontowanych z pojazdów po długotrwałej eksploatacji. Zaproponowano nowy ilościowy sposób określenia struktury warstw azotowanych i granic jej tolerancji dla konkretnych warunków eksploatacji w warunkach skoncentrowanego naprężenia stykowego.

EN

The influence low-pressure nitriding - NITROVAC, on the state of the residual stresses in the surface layers of M2HSS steel, were investigated. The data base of the residual stresses distribution in the surface layers with use of Waismann-Philips method was elaborated. At the example of the cam mechanism of injection pump DPA, the numerical model for superposing the residual stresses and those coming from the external loads is shown. The simulation was made with use of Finite Element Method and the standard program ANSYS 5.4. The criteria of the occurrence of the particular contact wear shapes (normal and abnormal) were defined on the base of virtual stress spectrum analysis. The results of the modelling were verified by the injection pumps observation, both at the probe stand and coming from the field tests. The new, quantitative way of the designation of nitrided layer structure, and boundaries of its tolerance for concrete exploitation circumstances in the concentrated contact stress conditional is proposed.

13

Obliczanie ewolucyjne w projektowaniu i wytwarzaniu

Kusiak A.

Inżynieria Maszyn

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2000

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R. 5, z. 1/2

54-65

PL

Biologia i technika informatyczna będą miały wpływ na projektowanie przyszłych produktów i procesów. W artykule omawiane są ważne zadania, stojące przed projektowaniem produktu i procesu. Wprowadza się pojęcie obliczania ewolucyjnego i omawia się jego potencjalne zastosowania w projektowaniu i wytwarzaniu.

EN

Biology and information technology will have an impact on the design of future products and processes. In this paper, the product and process design challenges are discussed. Evolutionary computation is introduced and its potential applications in design and manufacturing are discussed.

14

Rozwój sztuki projektowania jako alternatywa metody prób i błedów

Pfitzner A.

Elektronika : konstrukcje, technologie, zastosowania

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2000

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Vol. 41, nr 10

6-11

PL

Przedmiotem artykułu jest ewolucja techniki projektowania technicznego. Autor porównuje dwie metody: metodę prób i będów oparta na intuicji i doświadczeniu oraz planowaną działalność trwórczą podbudowaną osiągnięciami naukowymi. Pierwsza jest zilustrowana przykładami z historii architektury i alchemii, zaś druga komputerowym wspomaganiem projektowania układów scalonych bardzo wielkiej skali integracji.

EN

Fundamental quality change in the history of technology is the subject of the paper. It shows a transformation from the technical activity based only on the intuition and experience successively gathered to many generations, to the planned creative based on the scientific methods and achievements. In other words, a substitution of the method of trials and mistakes by the conscious technical design is discussed. This two methods are compared and briefly chracterised. The first is ilustrated using examples in the dield of architekture and alchemy. The systematic design is shown as an result of the closer relationships between science and technology. The computer aided design is also presented in the context of the design methodology development nad is ilustrated by the design of the integrated circuits. Artistic and chemistic aspects of the design are also mentioned.