Formal method for planning the machining of ship machine parts

2021 ◽  
pp. 39-46
Author(s):  
В.Е. Лелюхин ◽  
О.В. Колесникова
Keyword(s):  
Machine Tools ◽  
Formal Method ◽  
Dimensional Space ◽  
Group Processes ◽  
Classical Geometry ◽  
Variable Approach ◽  
Manufacture Article ◽  
Machine Parts ◽  
Formal Design ◽  
Convergence Of Algorithm

При разработке технологии изготовления судовых машин, узлов и деталей используются типовые процессы-аналоги, либо описание опыта исполнителей. Известные зарубежные подходы также используют вариативный подход, основанный на типовых решениях, либо генеративный, который предусматривает как формализацию процесса проектирования, так и использование искусственного интеллекта. Как показано в статье одной из основных проблем формализации проектирования технологических процессов является невозможность однозначного представления геометрической конфигурации реальных деталей средствами современной классической геометрии. Для решения этой проблемы предлагается использовать геометрию неидеальных объектов, базисом которой является шестимерное пространство, объединяющее три линейных и три угловых измерения. Использование указанной геометрии позволило определить формальные связи между конструкцией детали и технологическим процессом её изготовления. В статье излагается разработанный авторами метод формального проектирования процессов обработки деталей на станках. Выявленные закономерности порождения геометрических конфигураций позволили разработать алгоритмы генерирования множества методов формообразования элементарных поверхностей. Также определены условия обеспечения сходимости алгоритма формирования комплектов технологических баз и последовательности их выполнения. Изложение материалов подтверждено рассмотрением процесса проектирования технологии обработки на примере реальной детали. When developing a technology for the manufacture of ship machines, units and parts, group processes are used, or a description of the experience of the performers. Well-known foreign approaches also use a variable approach based on standard solutions, or a generative one, which provides for both the formalization of the design process and the use of artificial intelligence. Main problem of formalizing the design of technological processes is the impossibility of an unambiguous representation of the geometric configuration of real parts by means of modern classical geometry. As a solution to this problem, it is proposed to use the geometry of non-ideal objects, the basis of which is a six-dimensional space that combines three linear and three angular dimensions. This geometry made it possible to determine the formal relationships between the design of the part and the technological process of its manufacture. Article describes the method developed by the authors for the formal design of the processing of parts on machine tools. Revealed patterns generation configurations of geometric made it possible to develop algorithms for formation a variety of methods for shaping elementary surfaces. Conditions for ensuring the convergence of algorithm for formation of sets of technological bases and the sequence of their implementation are determined. Presentation materials is confirmed by considering generating of technology using the example of a real part.

Komponentendämpfung als Werkzeug zur dynamischen Optimierung von Werkzeugmaschinen/Damping Properties of Machine Parts as a Tool to 0ptimize the Dynamic of Machine Tools

Konstruktion ◽  
2018 ◽  
Vol 70 (05) ◽  
pp. 76-82
Author(s):  
Christian Brecher ◽  
Daniel Christoffers ◽  
Michael Wagner ◽  
Marcel Fey
Keyword(s):  
Machine Tools ◽  
Wird Eine ◽  
Damping Properties ◽  
Machine Parts

Inhalt: In diesem Fachartikel soll der Einfluss der Dämpfungseigenschaften von Maschinenelementen auf das dynamische Maschinenverhalten untersucht werden. Hierzu wird das an der RWTH Aachen erlangte Wissen bezüglich dieser Eigenschaften angewendet und die Frage betrachtet, wie die gewonnenen Erkenntnisse im Konstruktionsprozess genutzt werden können. Zudem soll auch ermittelt werden, welche Genauigkeit bei der Bestimmung der Dämpfungsparameter notwendig ist. Zur Beantwortung dieser Fragen wird anfangs untersucht, welchen Einfluss ausgewiesene Modifikationen auf die Prozessstabilität und daraufhin, welchen Einfluss die Modifikationen auf die dynamische Nachgiebigkeit haben. Hierzu wird eine anhand einer Modalanalyse ausgewählte Mode untersucht und schließlich die gesetzten Fragestellungen beantwortet.

DEVELOPMENT OF STANDALONE SOFTWARE SOLUTIONS BASED ON GEOMETRIC KERNELS FOR CREATING DIGITAL ASSEMBLY MODELS OF MACHINE TOOLS

2020 ◽  
Vol 13 (3) ◽  
pp. 86-93
Author(s):  
Aleksey Yurov ◽  
V. Antsiferova
Keyword(s):  
Design Process ◽  
Machine Tools ◽  
Scientific Computing ◽  
Human Factor ◽  
Parametric Models ◽  
Technological Equipment ◽  
Electronic Catalogs ◽  
Machine Parts ◽  
Assembly Models

The article discusses approaches and solutions aimed at increasing the productivity of engineering departments, where CAD software solutions are actively used. In the manufacture of machine parts, it becomes necessary to design technological equipment. Elements of machine tools can be prepared and placed in electronic catalogs (libraries), which in an automated mode will create a set of parametric models of the required technological equipment of machine tools. In this case, the accuracy and quality of modeling will be achieved by excluding the human factor from the design process. The development of such software solutions is implemented by means and components of the open geometric kernel Open Cascade, which has great potential both in the field of modeling and scientific computing.

scholarly journals Construction of Plastic Parts on CNC Engraving Machines and 3D Printers

2018 ◽  
Vol 55 (1) ◽  
pp. 75-78
Author(s):  
Dan Prodan ◽  
Anca Bucuresteanu ◽  
Adrian Motomancea
Keyword(s):  
Machine Tools ◽  
Low Cost ◽  
Special Equipment ◽  
3D Printers ◽  
Machine Parts ◽  
Plastic Parts ◽  
Toothed Gears

This work presents some of researches performed by the authors on execution of plastic parts required for repair works specific to certain machines and plants. Authors focused especially on the repair and reconditioning of certain assemblies which include various machine parts: special spacers, machine-tools guides and toothed gears. Methods shown herein are very simple, accessible even to small workshop and they do not require special equipment, thereby involving minimal expenses. The use of simple programs allow fast and low-cost execution of parts with an accurately determined geometry.

Improving the efficiency of surface-thermal hardening of machine parts in conditions of combination of processing technologies, integrated on a single machine tool base

2021 ◽  
Vol 23 (3) ◽  
pp. 45-71
Author(s):  
Vadim Skeeba ◽  
◽  
Vladimir Ivancivsky ◽  
Keyword(s):  
Surface Layer ◽  
Energy Consumption ◽  
Machine Tool ◽  
Machine Tools ◽  
Energy Sources ◽  
Technological Equipment ◽  
Thermal Hardening ◽  
Processing Technologies ◽  
Machine Parts ◽  
Hybrid Machine

Introduction. In the manufacturing industry, there is a particular interest in the development of a new type of technological equipment, which makes it possible to implement methods for modifying the parts surface layers by processing it with concentrated energy sources. The combination of two processing technologies (mechanical and surface-thermal operations) in the conditions of integrated equipment makes it possible to neutralize the disadvantages of monotechnologies and obtain new effects that are unattainable when using technologies separately. The use of hybrid machine tools in conjunction with the developed technological recommendations will allow achieving a multiple increase in the technical and economic efficiency of production, resource and energy saving, which in turn will contribute to an increase in the competitiveness of products and the renewal of the technological paradigm. Purpose of work: increasing productivity and reducing energy consumption during surface-thermal hardening of machine parts by exposure to concentrated energy sources under conditions of integrated processing. Theory and methods: studies of the possible structural composition and layout of hybrid equipment during the integration of mechanical and surface-thermal processes are carried out taking into account the main provisions of structural synthesis and the components of metalworking systems. Theoretical studies are carried out using the basic provisions of system analysis, geometric theory of surface formation, design of metalworking machines, finite-element method, mathematical and computer simulation. Mathematical simulation of thermal fields and structural-phase transformations in the case of HEH HFC is carried out in the ANSYS and SYSWELD software packages, using numerical methods for solving the differential equations of unsteady thermal conductivity (Fourier's equation), carbon diffusion (Fick's second law), and elastoplastic behavior of the material. The verification of the simulation results is carried out by conducting field experiments using: optical and scanning microscopy; mechanical and X-ray methods for determining residual stresses. In the study, Uone JD520 and Form Talysurf Series 2 profilograph-profilometers are used to simultaneously measure shape deviations, waviness and surface roughness. Surface topography is assessed using a Zygo New View 7300 laser profilograph-profilometer. The microhardness of the hardened surface layer of parts is evaluated on a Wolpert Group 402MVD device. Results and discussion. An original method of structural-kinematic analysis for pre-design research of hybrid metalworking equipment is presented. Methodological recommendations are developed for the modernization of metal-cutting machine tools, the implementation of which will allow the implementation of high-energy heating by high-frequency currents (HEH HFC) on a standard machine-tool system and ensure the formation of high-tech technological equipment with expanded functionality. A unified integral parameter of the temperature-time effect on a structural material is proposed when the modes of hardening by concentrated heating sources are assigned, which guarantee the required set of quality indicators of the surface layer of machine parts, while ensuring energy efficiency and processing productivity in general. It is experimentally confirmed that the introduction into production of the proposed hybrid machine tool in conjunction with the developed recommendations for the purpose of the HEH HFC modes in the conditions of integral processing of a “Plunger bushing” type part in relation to the factory technology allows increasing the productivity of surface hardening by 3.5 ... 4.1 times, and reduce energy consumption by 9.5 ... 11.3 times.

scholarly journals Analysis of the eigenfrequencies of the basalt machine parts by the FEM

2021 ◽  
Vol 343 ◽  
pp. 08002
Author(s):  
Ilie Octavian Popp
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Machine Tools ◽  
Structural Elements ◽  
The Finite Element Method ◽  
Finite Element Program ◽  
Element Program ◽  
Beam Type ◽  
Machine Parts ◽  
Plate Type

The aim of this paper was to carry out a theoretical (numerical) scientific research on the behavior of cast and recrystallized basalt, in order to use it as a material in the manufacture of structural elements of machine tools. A unitary methodology has been established for studying the eigenfrequency of structural elements for machine tools by the finite element method. Two basalt structural elements (beam type and plate type) were modeled, which were also made physically, and with the help of the COSMOS / Mark finite element program, the eigenfrequencies of the models was studied.

The motion of a lunar orbiter

1966 ◽  
Vol 25 ◽  
pp. 373
Author(s):  
Y. Kozai
Keyword(s):  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Artificial Satellite ◽  
Equations Of Motion ◽  
Triaxial Ellipsoid ◽  
The Moon ◽  
Secular Motion ◽  
The Earth ◽  
Close Satellite ◽  
The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

The Chatterbox: A Device for Hearing Chatter as Sections are Cut

1973 ◽  
Vol 31 ◽  
pp. 360-361
Author(s):  
C. W. McCutchen ◽  
Lois W. Tice
Keyword(s):  
Machine Tools ◽  
Cutting Tool ◽  
Guerilla Warfare ◽  
History Of ◽  
Chatter Marks

Ultramicrotomists live in a state of guerilla warfare with chatter. This situation is likely to be permanent. We can infer this from the history of machine tools. If set the wrong way for the particular combination of cutting tool and material, most if not all machine tools will chatter.In more than 100 years since machine tools became common, no one has evolved a practical recipe that guarantees avoiding chatter. Rather than follow some single very conservative rule to avoid chatter in all cases, machinists detect it when it happens, and change conditions until it stops. This is possible because they have no trouble telling when their cutting tool is chattering. They can see chatter marks, and they can also hear a sometimes deafening noise.

Three Dimensional structure and organization of diploid chromosomes by optical section microscopy

1987 ◽  
Vol 45 ◽  
pp. 633-635
Author(s):  
David A. Agard ◽  
Yasushi Hiraoka ◽  
John W. Sedat
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Developmental State ◽  
Mitotic Cell ◽  
Biological Properties ◽  
Dimensional Structure ◽  
Specific Gene ◽  
Three Dimensional Structure ◽  
Complementary Techniques ◽  
Dynamic Structures

In an effort to understand the complex relationship between structure and biological function within the nucleus, we have embarked on a program to examine the three-dimensional structure and organization of Drosophila melanogaster embryonic chromosomes. Our overall goal is to determine how DNA and proteins are organized into complex and highly dynamic structures (chromosomes) and how these chromosomes are arranged in three dimensional space within the cell nucleus. Futher, we hope to be able to correlate structual data with such fundamental biological properties as stage in the mitotic cell cycle, developmental state and transcription at specific gene loci.Towards this end, we have been developing methodologies for the three-dimensional analysis of non-crystalline biological specimens using optical and electron microscopy. We feel that the combination of these two complementary techniques allows an unprecedented look at the structural organization of cellular components ranging in size from 100A to 100 microns.

Diffraction contrast of dislocations in icosahedral quasicrystals

1990 ◽  
Vol 48 (4) ◽  
pp. 454-455
Author(s):  
K. Urban ◽  
Z. Zhang ◽  
M. Wollgarten ◽  
D. Gratias
Keyword(s):  
Dimensional Space ◽  
Three Dimensional ◽  
Complete Characterization ◽  
Extinction Condition ◽  
Burgers Vector ◽  
Diffraction Contrast ◽  
Lattice Geometry ◽  
Reference Space ◽  
Icosahedral Quasicrystals ◽  
The One

Recently dislocations have been observed by electron microscopy in the icosahedral quasicrystalline (IQ) phase of Al65Cu20Fe15. These dislocations exhibit diffraction contrast similar to that known for dislocations in conventional crystals. The contrast becomes extinct for certain diffraction vectors g. In the following the basis of electron diffraction contrast of dislocations in the IQ phase is described. Taking account of the six-dimensional nature of the Burgers vector a “strong” and a “weak” extinction condition are found.Dislocations in quasicrystals canot be described on the basis of simple shear or insertion of a lattice plane only. In order to achieve a complete characterization of these dislocations it is advantageous to make use of the one to one correspondence of the lattice geometry in our three-dimensional space (R3) and that in the six-dimensional reference space (R6) where full periodicity is recovered . Therefore the contrast extinction condition has to be written as gpbp + gobo = 0 (1). The diffraction vector g and the Burgers vector b decompose into two vectors gp, bp and go, bo in, respectively, the physical and the orthogonal three-dimensional sub-spaces of R6.

Flavin radicals, conformational sampling and robust design principles in interprotein electron transfer: the trimethylamine dehydrogenase-electron-transferring flavoprotein complex

2004 ◽  
Vol 71 ◽  
pp. 1-14
Author(s):  
David Leys ◽  
Jaswir Basran ◽  
François Talfournier ◽  
Kamaldeep K. Chohan ◽  
Andrew W. Munro ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Kinetic Studies ◽  
Molecular Assembly ◽  
Conformational Sampling ◽  
Trimethylamine Dehydrogenase ◽  
Key Residues ◽  
Electron Transferring Flavoprotein ◽  
Electron Transfer Complex

TMADH (trimethylamine dehydrogenase) is a complex iron-sulphur flavoprotein that forms a soluble electron-transfer complex with ETF (electron-transferring flavoprotein). The mechanism of electron transfer between TMADH and ETF has been studied using stopped-flow kinetic and mutagenesis methods, and more recently by X-ray crystallography. Potentiometric methods have also been used to identify key residues involved in the stabilization of the flavin radical semiquinone species in ETF. These studies have demonstrated a key role for 'conformational sampling' in the electron-transfer complex, facilitated by two-site contact of ETF with TMADH. Exploration of three-dimensional space in the complex allows the FAD of ETF to find conformations compatible with enhanced electronic coupling with the 4Fe-4S centre of TMADH. This mechanism of electron transfer provides for a more robust and accessible design principle for interprotein electron transfer compared with simpler models that invoke the collision of redox partners followed by electron transfer. The structure of the TMADH-ETF complex confirms the role of key residues in electron transfer and molecular assembly, originally suggested from detailed kinetic studies in wild-type and mutant complexes, and from molecular modelling.

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