ISSN 0021-3454 (print version)
ISSN 2500-0381 (online version)
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Summaries of the issue

INFORMATION TECHNOLOGIES AND SYSTEMS, COMPUTING TECHNIQUE

391
Specific of errors that occur in ternary code vectors due to distortions of one or more digits and are characterized by multiplicity and type, are considered. A classification of errors in ternary code vectors is pro-posed, and comparison with errors occurring in binary code vectors is performed. Definitions of various types of errors in binary and ternary code vectors are given, and examples are presented to illustrate features of such errors. The classification of errors in ternary code vectors allows to develop data encoding principles for detecting errors of a certain type and use them in both data transmission and synthesis of devices functioning in ternary logic that have the property of detecting faults. Some methods of constructing ternary codes aimed at detecting errors in information vectors or in code words in general are described. It is stated that the results can be used for developing a basis for synthesis of reliable and safe automation devices operating in ternary logic.
Formation of Ternary Sequences with High Structural Secrecy in Digital Information Trans-fer Systems Victor G. Starodubtsev, Vladimir V. Tkachenko, Elizaveta A. Bobrova
405
An algorithm for determining initial states of shift registers included in the Gordon-Mills-Welch (GMW) ternary sequence generation device with the period of N = 728 is presented. The algorithm is based on comparison of the initial states obtained by solving the system of linear equations in the finite fields and the states determined by decimation of characters of the basic M-sequence. Ternary M-sequences and GMW-sequences have the same two-level periodic autocorrelation function, but different structural secrecy, characterized by equivalent linear complexity. The GMW-sequence is formed using a basic M-sequence with a similar period when it is presented in the form of quasi-square matrix. It is shown that for each of the 48 primitive polynomials in the finite field GF (36), three GMW-sequences can be formed. For binary GMW sequences, the initial states of the shift registers are formed by decimating the symbols of the basic M-sequence, presented in canonical form, by decimation indices corresponding to the roots of indivisible polynomial factor factors. For ternary GMW sequences, the individual summable components have an additional half-period shift of the base M-sequence. It is argued that the obtained results can be used for generating broadband non-binary signals in digital information transmission systems.

DEVICES AND SYSTEMS OF AUTOMATIC CONTROL

Power Converter with Active Suppression of Higher Harmonics for Aircraft Power Supply Systems Alecksey S. Anuchin , Vasily I. Kulmanov, Strzelecki Ryszard , Galina L. Demidova
417
Two active filtering algorithms for a power converter with active suppression of higher harmonics are presented. The first algorithm is based on the discrete Fourier transform: by means of a synthesized control system, the inverted measured higher voltage harmonics are fed to the input of the inverter. The second con-trol method is based on an algorithm using the principle of self-learning, which significantly reduces the need for computing resources. Active voltage filtering in both systems provides the required output voltage quality with a harmonic distortion factor of less than 5% over the entire load range. Results of modeling and experi-mental investigation of a power converter for aircraft power supply with a sine-filter at the output are present-ed.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

Synthesis and Analysis of Interference Coating Structures for an Augmented Reality System Based on a Lightguide Combiner Gubanova Lyudmila Alexandrovna, Roman Е. Zeigman , Tatiana А. Koneva , Romanova Galina Eduardovna
429
Results of synthesis of interference coating structures used in an augmented reality system based on a lightguide combiner are presented. The lightguide combiner is made up of prisms with original coatings applied to their faces. Optical characteristics of the coatings at different angles of radiation incidence are considered and the structures of the coatings including layers made of refractory oxides with high transparency in the visi-ble spectrum range are calculated. As a result of the synthesis, coatings consisting of layers of unequal and non-multiple thickness are obtained. It is shown that multilayer coatings based on dielectric layers of non-equal thickness provide a constant reflection (transmittance) coefficient in the spectral range of interest for a given range of incident radiation angles. Correct operation of the optical system with developed interference coatings is demonstrated by presented results of computer simulation.

INSTRUMENT-MAKING TECHNOLOGY

436
A methodology for calculating and designing small-sized cylindrical kinematic gears made of mainly structural polymer-composite materials is proposed. The technique consists of four main successive stages, in which the basic calculation formulas are presented. The features of the use of composite materials for gears are determined. Recommendations are given on improving the gear transmission parameters based on the experience of cone-wedge ring gears employment.
Dynamics Analysis of the Membrane Elastic Element with Attached Concentrated Mass Tkalich Vera L., Mariia E. Kalinkina, Korobeynikov Anatoliy Grigorievich, Pirozhnikova Olga I.
444
The dynamics of unsteady oscillations of a rectangular membrane with one and two attached masses is studied. Adequate mathematical models are constructed using methods for solving direct problems in the mechanics of an elastically deformable body, namely, the Volterra equations and the Cramer method. It is noted that the obtained solution of the direct problem has an experimental application to the problems of analy-sis of displacements, deflections, deformations and stresses during unsteady vibrations of membranes with at-tached concentrated mass used in switching elements (membrane reed switches) and micromechanical pres-sure sensors. Based on the developed mathematical models, calculations of membrane elastic elements of a patented series of switching elements and pressure sensors are performed.
Tests of Multi-Chip IGBT-Modules for Resistance to Cyclic Power Current Vladimir V. Verevkin, Stanislav L. Strigunov, Anastasia P. Pilipenko, Kirill A. Volobuev, Valentina A. Lobanova
451
Results of experimental study of multi-chip IGBT-modules with different position of transistors on DBC are presented. A system for power cycling tests of IGBT-modules is developed. Experiments carried out to compare the multi-chip IGBT modules with different position of transistors on DBC after power tests in electro thermal cyclic mode demonstrate that the topology of multi-chip modules (the position of transistors on DBC) has an effect on the temperature distribution between the chips. The main features of the test setup include accurate monitoring of the sample status using two temperature sensitive parameters and high reliability of the test equipment. During the test with a type K thermocouple and the thermal imager, the temperature distribu-tion between the parallel connected chips of the tested samples and other conductive elements of the sam-ples, including copper wire bond connections, were calculated. The received data allowed to obtain experi-mental dependency curves for the electrical parameters of the tested modules vs the number of cycles to fail-ure. This can help to estimate the degradation degree of a sample before its failure. The temperature sensitive parameter value and, consequently, number of cycles to failure of a multi-chip module is found to depend on the hottest chip temperature. It is also found that the temperature of some wire bond connections in the multi-chip module can be comparable to the chip temperature and can cause the module constructive elements degradation due to the thermomechanical stress. These results can be used in development and design of the multi-chip IGBT-modules.
Investigation of Surface Pro¬perties of Alloys Using Indentation Instruments Margarita A. Skotnikova, Alexandеr A. Popov, Galina V. Ivanova, Galina V. Tsvetkova
460
Using indentation instruments, the features of elastoplastic deformation of samples made of alloys are investigated. The alloys of aluminum AMc, titanium VT23, and steels 45, HVG with FCC, HCP and BCC lattices, respectively, are studied. It is shown that when indentation depth increases, instrumental hardness (H1T), elastic modulus (Е1T), and their ratios (НIT / EIT) tend to the values of classical microhardness Нµ, Young's modulus E, and their ratio (Нµ/E). The nature of localization of plastic deformation of alloys near the surface of the indenter is analyzed. The reason for the hard workability of titanium-based alloys is determined.

SCIENTIFIC AND PRACTICAL DEVELOPMENTS

Algorithm of Structural-Parametric Synthesis of Adaptive Gripper Mechanisms with Varia-ble-Length Links Ivan I. Borisov, Roman A. Zashchitin, Olga V. Borisova, Kolyubin Sergey A
467
An algorithm is proposed for the structural and parametric synthesis of finger mechanisms of universal gripping devices that can solve problems of reliable manipulation of objects of arbitrary shape under external static contact influences and the use of relatively simple position and speed controllers. The required performance characteristics are achieved due to the mechanical decomposition of the control channels, in particular due to introduction of active or passive units of variable length into the robot design. The algorithm can be used to synthesize the mechanisms of both industrial gripping devices and anthropomorphic hand prostheses.
Optimization of the Structure and Properties of the Al-Cu-Mg System Aluminum Alloy Olga V. Paitova, Elena V. Bobruk, Margarita A. Skotnikova
476
Results of experimental investigation of aluminum alloy D16 of the Al-Cu-Mg system are presented. Using optical metallography, scanning electron microscopy, and electrical conductivity tests, the tendency of the alloy to natural and artificial aging after quenching and intense plastic torsion deformation under 6 GPa pressure at room temperature is studied. Dependences of the alloy microhardness and electrical con-ductivity on holding time are revealed. It is shown that heat treatment (quenching + intense plastic torsion de-formation + artificial aging) leads to a 2.3-fold increase in the hardness of the D16 alloy as compared to the standard HT (T4), while maintaining the level of electrical conductivity.
Automated Complex for Dynamic Positioning of a Person in a Gravitational Field Michael L. Podvyaznikov, Flexander A. Novichkov, Petr I. Tolkachev, Oleg А. Viktorov, Sergey V. Bozhokin , Nikita P. Tolkachev
483
An automated system for dynamic positioning Mechanor SA-05 developed and manufactured by JSC Obukhov Plant, is presented. The complex makes it possible to automatically control a human body move-ment in the gravitational field using a computer program that sets various directions and speeds, amplitudes, and angular vibrations. The complex is used for diagnostics and treatment of respiratory, cardiovascular, cen-tral and peripheral nervous systems, musculoskeletal system, as well as activation of microcirculation of blood and other biological fluids. Based on the wavelet theory, quantitative parameters of non-stationary ECG, EEG, pulse wave and respiratory rhythms were determined during dynamic orthostatic tests.