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

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

TRAJECTORY CONTROL OVER RIGID BODY MOVEMENT RELATIVE TO A MOBILE OBJECT Krasnov Aleksander Yu., Kapitanyuk Yuri A, Chepinsky Sergey A, Sergey A. Kholunin, Liu Huimin , Denis A. Khvostov, Chen Yifan
1003
The problem of synthesis of trajectory control algorithm for rigid body model in a moving frame is considered. Adopted mathematical description of the body is represented by a dynamic model with unidirectional thrust. A procedure for synthesizing the laws of trajectory control using differential geometry methods that solve the problem of motion relative to a mobile object is proposed. The efficiency of the synthesized control laws is confirmed by presented results of digital simulation.
1012
The problem of criterium formulation is considered as an important part of multidimensional estimation methods. The proposed formalization of the concept of criterium allows to establish a relation between methods developed in the framework of different theories and to separate the selecting methods into two groups.
1016
Design and principle of operation of developed two-dimensional electromagnetic-type sensor intended for fixing various movements of an object are presented. Results of experimental study of the sensor demonstrate the possibility of reducing the dimensions of the housing of the sensor and simplify its design. It is shown that when operating the sensor, the amplitude of the output voltage is converted into a code that is passed to the chain drives and manages their work. Because the conversion accuracy of stresses into the codes is much less important than the conversion accuracy of the sensor, it has almost no effect on the error of the measurement channel. From this point of view, the development and application of two-dimensional inductive sensor systems for numerical control machines used in engineering are of great importance.

COMPUTING TECHNIQUE

EFFECTIVE METHOD OF MODIFYING CODE WITH ON-BITS SUMMATION Sapozhnikov Valery V., Sapozhnikov Vladimir V., Ephanov Dmitry V.
1020
A new principle of modification of codes with summation of on-bits that allows to expand the class of modified codes and obtain codes with better characteristics of low multiplicity error detection is proposed. An overview of known methods of classical codes modifications with summation of individual information bits is presented. A method of constructing modified codes with summation, based on determination of the smallest nonnegative deduction weight incomplete information vector and control of "unused" information bits by using the correction coefficient, which is a convolution modulo two is described; in particular, the correction factor may include discharge, subject to a deduction of the weight. All the possible ways of constructing error-correcting codes modified with the summation are considered. Characteristics of error detection in the information vectors of these codes are analyzed.  The conditions, under which a code with summation detects the maximal number of double errors in the information vectors and the conditions under which the code will have the minimum number of monotone non-detectable errors are established. The presented principle of codes modification is shown to allow for increasing the number of well-known codes used in technical diagnostics of discrete systems.
1033
The discipline and a model of redundant service of request copies are proposed for a system with nodes represented by single-channel queuing model, in the case when different priorities of service are assigned to different backup requests. A request is considered handled successfully if at least one of its copies is served correctly. Possible ways to improve the efficiency of redundant service system by distributing priorities of backup requests. The efficiency of the proposed discipline of redundant priority service is demonstrated.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

1040
A way to control of CCD image sensor is proposed which allows active-pulse method of surveillance without using an image intensifier in the device. A positive effect is achieved by using the structural features of interline transfer CCD image sensor. The efficiency of the proposed approach is confirmed experimentally.
1048
A method is presented for analysis of manufacturing errors of the layers forming the optical coating structure to determine the layer that contribute most to the spectral characteristics of the coating. Sensitivity of the interference coatings to deviation of the layer geometric thicknesses from calculated value is estimated for each of the layers. In the process of identifying the layer which contributes most to the coating spectral characteristics stability, all the layers thicknesses are alternately replaced with a set of values differing from the calculated by a known amount. For the newly obtained structure, a merit function is evaluated. The layer, which corresponds to the maximum value of the merit function, is considered to be the most sensitive to geometric inaccuracies of manufacture.
1054
Analysis of refractive index gradient and design of a positive lens providing atypical correction of image field curvature is presented. The results are employed in design of optical schemes of endoscopic type and Pin Hole lenses.
1060
Relations between parameters of the trihedron-shaped reflector for autocollimation-based measurements of rotation angle are analyzed. In comparison to flat mirror, the use of the reflector allows to increase the operational distance of autocollimation measurements. Special configuration of the trihedron with reflective edge in the form of two separated sections is considered. It is shown that application of such configuration makes the effective reflection surface more than three times as large as for existing trihedron reflectors.

INSTRUMENT-MAKING TECHNOLOGY

1064
Experimental data on acoustic characteristics of the working area of cutting equipment in the idle mode are analyzed. Parameters are determined that affect the frequency characteristics of the active system recognized by the value of the error in relative position of groups of elements. Relationship between of the rotary milling system runout in the absence of applied load and the noise level recorded by sound analyzers is established. A method is proposed for predicting the level of vibrational activity of a milling system in the cutting zone that occurs during the finishing of hard-to-work materials.
FORMATION OF ANTIREFLECTION MICRORELIEF ON SILICON SURFACE IRRADIATED WITH NANOSECOND ITTERBIUM LASER Polyakov Dmitry S., Veiko Vadim Pavlovich, Aleksander A. Shimko , Nikolay M. Salnikov, Mikhaylova Aleksandra A.
1070
Specifics of morphology of microrelief formed on monocrystalline silicon surface under the action of series of nanosecond laser pulses of ytterbium fiber laser with intensities close to melting threshold are studied. It is shown that at multi-pulse irradiation the relief consist of micro cones with surface concentration depending on laser power density. The obtained microrelief has antireflective properties and its formation leads to decreasing of full reflection coefficient for 3—4 times in comparison with initial value.

SCIENTIFIC AND PRACTICAL DEVELOPMENTS

1077
The problems of the application and development of modern technologies in the field of driver assistance systems of the vehicle are considered. Systematizes of the technologies used today is carried out. Main classes of subsystems, responsible for different functions of the considered systems are recognized. A comparative analysis of several existing systems is presented. Potential of driver support systems and their openness to new developments are noted, as well as enhancing role of external services for systems of this class.
RASTER STRUCTURES AND VISION Fedorov Yury V., Fedorova Alexandra Yu.
1083
The simplest systems based on camera obscura to obtain an optical image of objects are considered. Raster structures located in front of the visual analyzer, initiate operation of the ciliary muscles of the eye to form a single sharp image on the retina. Properties of various raster structures are described, the possibility of the structures application as eye visual simulators are discussed.
HARDWARE AND SOFTWARE SYSTEM FOR CHROMATOGRAPHIC DETECTOR OF THERMAL CONDUCTIVITY IN THE MUSUN EXPERIMENT Ivshin Kuzma A., Peter A. Kravtsov, Viktor A. Trofimov, Kiselev Sergey S.
1088
Basic technical and methodical approaches to the problem of chemical impurities measurements in hydrogen are described. Two ways of increasing sensitivity have been developed in the international nuclear experiment MuSun. The first one is a modification of the sampling procedure. The second one is improvement of the measurement system based on a chromatograph. These techniques provide precise measurements of the atmospheric impurities concentration in hydrogen at the level of 1ppb (part per billion).

BRIEF NOTES

TEMPORAL ANALYSIS OF H.264 CODEC Sergey V. Kuleshov, Alexandra A. Zaytseva
1092
An approach to analysis of digital video stream compressed by H.264 video codec aimed at optimization of encoding parameters is proposed. Comparative analysis of various popular realizations of H.264 is presented. The proposed approach can be used as a tool to obtain the list of H.264 technologies implemented in given codec realization. The results of analysis provide an ability to optimize coding parameters for various usage scenarios.