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Vartanov M.V.,University of Mechanical Engineering | Bojkova L.V.,University of Mechanical Engineering | Zinina I.N.,University of Mechanical Engineering
Assembly Automation | Year: 2017

Purpose - The purpose of this paper is to define the conditions for a failsafe coupling of parts when using adaptation and low-frequency vibrations. A model enables us to determine the reaction at the contact points of parts and time-based contact conditions changes. Therefore, the conditions of jamming parts can be defined in the process of conjugation. Design/methodology/approach - A mathematical model describing the trajectory of the part mass center in robotic assembly is created. An experimental equipment is also presented in the paper. Convergence of theoretical and experimental results that characterize the reliability of processes is estimated. Findings - The mathematical model of the connection process dynamics is found in the form of Lagrange's equations of the second kind. Originality/value - Applying low-frequency vibration and the adaptive gripper is proposed to extend technological capabilities of robotic assembly. © 2017 Emerald Publishing Limited.


Kalenkov S.G.,University of Mechanical Engineering | Kalenkov G.S.,Moscow Institute of Physics and Technology | Shtanko A.E.,Moscow State University
Optics Express | Year: 2013

We propose a novel method to obtain non-lens holographic images of micro-objects in white light with diffraction limit quality, based on fourier-spectroscopy principles. We developed a simple method for numerical acquisition of digital holograms of micro-objects at any spectral component from the set of two-dimensional interferograms, registered by fourier-spectrometer. In our experiments we used spectrally-spatial holographic fourier-spectrometer (SSHFS), equipped with supercontinuum light source and CCD camera for registration. Holographic images of several test objects acquired experimentally at different spectral components are presented. Visualization of local spatially-spectral inhomogeneities of micro-objects is discussed through the example of silver berry scaly hair sample. © 2013 Optical Society of America.


Kalenkov S.G.,University of Mechanical Engineering | Kalenkov G.S.,Moscow Institute of Physics and Technology | Shtanko A.E.,Moscow State University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

Novel method is suggested for a hyperspectral wave field holographic recording, based on asymmetrical Fourier spectrometer with a flat microobject placed in one of its arms. The output signal, which is the interference of the reference field with the field diffracted by the object, is registered by CCD. The process of recording is reduced to consecutive registration of two-dimensional interferograms by changing the optical length of the reference arm of the interferometer. One-dimensional Fourier transform of the interferogram in each pixel gives a spatial distribution of the complex amplitude for all spectral components of a hyperspectral object field. Inverse Fresnel transform of this field gives a hyperspectral object field in the object plane. Hyperspectral amplitude and average-phase profile images of standard microscope samples obtained experimentally are presented. Coloring, Fellgett's advantage and speckle noise © 2015 SPIE.


Kalenkov G.S.,Moscow Institute of Physics and Technology | Kalenkov S.G.,University of mechanical engineering | Shtanko A.E.,Moscow State University
Optics InfoBase Conference Papers | Year: 2014

New lens free holographic image acquisition method in polychromatic, unpolarized light is presented. Hyperspectral amplitude and average-phase profile images of standard microscope samples obtained experimentally are presented, speckle noise reduction is discussed. © 2014 OSA.


Petrov M.A.,University of Mechanical Engineering | Petrov A.N.,University of Mechanical Engineering | Petrov P.A.,University of Mechanical Engineering
Key Engineering Materials | Year: 2016

In modern technological operation, the original sample could be provided by so-called pre-operation or pre-forming follows prior the main operation. In such case, the surface roughness of the tool set is directly owned by the surface of the pre-formed workpiece, as less rigid body compared with the tool set. In metal forming practice there are mainly several pre-forming processes, among them roll forging, cross-wedge rolling and electro-upsetting. In any nonconvenient forging operation route, where pre-forming is done by casting, powder sintering or any additive technology (e.g. SLS, EBM), the surface roughness and wellness obtained pre-formed workpiece could influence stronger on the quality of the end part after main forging operation. In order to investigate the different materials' behaviours depends on the surface artificial roughness the finite-element analysis (FEA) was carried out for the simple compression tests, thereby the cylindrical, made from aluminium and titanium alloys, and ring specimens, made from steel, were compressed between two flat dies with modelled zero and non-zero roughness at room and elevated temperatures. The behaviour of the lubricant (fluid phase) positioned between two neighboured peaks of the roughed surface was investigated in one direction material flow test as well. The results have shown the strong pressure increase in the bottom area of the peaks, which correspond the practice case, when the fluid phase is not completely evaporated after lubrication. Further, it can course the different microstructure evolution during hot forging operation and during cold bulk forming operation, additional surface pressure can result the material hardening near to the contact zone (not investigated here). In commonly, in observed results the peaks of the roughness can be easily broken due to enormous tangential stresses, as it is well known from the fundamental investigations. Moreover, the computation of geometry scaled tools and workpieces of the ring compression and one-direction material flow tests resulted the exponential dependency against the deformation forces. © 2016 Trans Tech Publications, Switzerland.


Petrov M.A.,University of Mechanical Engineering | Petrov P.A.,University of Mechanical Engineering | Yafaev R.R.,University of Mechanical Engineering
Key Engineering Materials | Year: 2015

In many technological processes, friction results strong wear of the tool set and causes defect forgings. Many experimental investigations started in XX century had shown, that there are some laboratory methods with trustable results, which can be applied for friction prediction in real processes of metal forming. Among them such tests like ring compression test, direct and backward extrusion test, double cup extrusion test and T-shape compression test can be selected. Each of them has limitations that do not allow distributing the results of one certain test on all metal forming processes. Moreover, the tests should be done in a proper way to guarantee adequate results that could be time-consuming. With the help of FE-analysis, the authors investigated numerically the intensity of the pressure distribution on the tool's surfaces and coupled the results with the real situations, observed in the metal forming operations. For the relative young T-shape compression technique oriented on the high contact pressure values authors have examined the changing of the relative deformed material volume as the merit of the friction characterisation. © (2015) Trans Tech Publications, Switzerland.


Sheldakova J.,University of Mechanical Engineering | Kudryashov A.,University of Mechanical Engineering | Rukosuev A.,University of Mechanical Engineering | Lylova A.,University of Mechanical Engineering
Proceedings - 2016 International Conference Laser Optics, LO 2016 | Year: 2016

Recent results of formation of uniform beam intensity distribution at the focal plane of a lens by means of bimorph deformable mirrors are presented. An approach based on the use of Shack-Hartmann wavefront sensor together with focal spot sensor (M2 meter) is suggested. Advantages and disadvantages are discussed. © 2016 IEEE.


Petrov M.,University of Mechanical Engineering | Petrov P.,University of Mechanical Engineering
Key Engineering Materials | Year: 2014

The present paper reveals one of the energy efficient ways of science investigation of materials for light construction purposes. The small hollow spheres made from different materials could change the weight of a construction part essentially, used as acoustic and thermal insulation and also as protection against vibrations. They can be used as a unit cell for big parts and alone filled with an inert gas, e.g. fusion targets. Pure tin shells were produced in transient (thixotropic) state of materials at elevated temperatures (close to the melting point of the pure tin melt) and several simulation steps were used, to determine the preferable boundary conditions. To one of them belongs the investigation of the temperature fields during the formation process. The formation force was determined theoretically. Also a theoretical assumption, that the solid material needs the same deformation force value or close to it, the numerical investigation was also carried out in FE-code QForm-3D. © 2014 Trans Tech Publications, Switzerland.


Sheldakova J.,University of Mechanical Engineering | Kudryashov A.,University of Mechanical Engineering | Lylova A.,University of Mechanical Engineering
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

It is desired to use some special intensity distribution on the target for various industrial applications. The adjusting of the intensity profile can be implemented by means of adaptive optics. In this paper we present laser beam control in the focal plane of lens with bimorph deformable mirrors. Hill-climbing method and stochastic algorithm are compared. Advantages and disadvantages of two methods are discussed. © 2015 SPIE CCC.


Kononov V.M.,University of Mechanical Engineering
Gornyi Zhurnal | Year: 2015

The article describes theoretical and exploratory research and its commercial trial (in Severomuysky tunnel) aimed at explosive charge control in blastholes with preset orientation cuts made in the blasthole walls, that allow concentrating blast energy along the cut orientation and, consequently, reduction in powder factor, "smooth" excavation perimeter after blasting with minimized overrun/underrun and damage of adjacent rock mass (fracturing). The bench testing involved fracturing of various strength concrete blocks by charges placed in blastholes with and without cuts of various orientation, depth and shape; the principle parameters and relations have been determined, including the relation between the blasting energy content reduction coefficient KE and the cut depth and angle for various strength blocks, as well as the powder factor reduction. The pilot blasts carried out at a commercial level, considering the parameters obtained in the tests, proved the efficiency of the new technology.

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