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

INFORMATION TECHNOLOGIES AND SYSTEMS, COMPUTER TECHNIQUE

799
The problem of choosing a target object from a set of objects in the observer's field of view by a limited number of measurements of dissimilar selective features, is considered. To solve the problem with a required probability for a various number of measurements of the individual features, a combined dimensionless feature is introduced. The proposed approach does not require accumulation of large volumes of measurement information and can be used to make decisions in the case of physical dissim-ilarity of the measured values.
806
A mathematical model for ships distribution across area is developed effectively solve the problem of oceanological research. The distribution of ships in the area of hydrographic survey of the bottom relief is considered. A dynamic programming method is presented, which ensures optimal distribution of the ships involved, conditions for the optimization method application are formulated.
811
Preparing low quality video images for payload extraction is considered as a challenging task in the field of imaging and computer graphics. The most frequently used methods of image quality improvement are reviewed, such as full or partial exposure change, as well as algorithms for spatial and frequency filtering. The selected algorithms and methods are analyzed with the account for peculiarities of neural network operation with a finite video sequence. Based on the study, the main parameters and criteria of video images were identified to ensure the correct operation of the neural network.
NATURAL VIBRATION FREQUENCY OF STRUCTURES FROM A MACHINE PROFILE CONNECTED WITH A CONCEALED CORNER Ekaterina E. Kopets, Artur I. Karimov, Denis N. Butusov , Vyacheslav G. Rybin
821
Structures made of aluminum machine tools are widely used in 3D printers and CNC machines design. The designer must account not only for the static deformations of such structures, but also for vibration characteristics since they directly affect the quality of the device operation. A mathematical model of construction composed of two machine profiles in the form of a linear elastic hinge is proposed, and its parameters are experimentally determined. Comparison of results obtained using the proposed model as well as simulated by the finite element method in the Fusion 360 package with experimentally measured data is performed. The conclusion is made about the best correspondence of the proposed mathematical model to experimental data.

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

829
The PID controller is the main element of a quadcopter control system. The influence of each of the three components of the stabilizing PID controller of a quadcopter on its behavior in the air is analyzed experimentally. Regime of automatic tuning of the regulator parameters is considered using the example of the Autotune mode as part of the Misson Planner software, a popular flight controller with an open Ardupilot architecture. With the help of mathematical modeling and experiments, an algorithm for tuning the stabilizing PID controller was derived from the generalized data. Practical value of the developed algorithm lies not only in the precise tuning of the PID controller, but also in the possibility of its further tune-up during operation. So, in the case of a change in the type, weight or attachment points of the payload, as well as in the flight conditions, it makes sense to change the “character” of the vehicle stabilization. For example, when flying with a camera, to maintain image stability at a high magnification ratio, the regulator operation should be smoother. In the case of flight tasks performing in windy weather, it is advisable to set other parameters of the regulator, and possibly to resort to operating in a mode with controlled overshoot.
MATHEMATICAL MODEL OF THE MULTIFUNCTIONAL STAR TRACKER Danilova Tamara V. , Arkhipova Marina A. , Мarina А. Мaslova
839
A mathematical model of a multifunctional onboard star tracker with an expanded set of capabilities is presented. The capabilities of the tracker, in addition to star recognizing and calculating its geocentric orientation, include functions of generating operational estimates of random errors in measurements of the stars coordinates and magnitudes in various formats. The estimates obtained are necessary to ensure the normal operation of the device under conditions of degradation caused by prolonged operation or the influence of other factors. The formed estimates can be used to solve the problem of spacecraft navigation in onboard control complex.
852
The features of data routing in a multi-satellite low-orbit system providing communication of ground subscribers with each other and with spacecraft are investigated. The issues of constructing an orbital constellation, in which communication satellites form a network segment with a static topology, are considered. In this case, routing, in fact, boils down to solving two problems: the search for communication satellites that are in the zone of radio visibility of communication session respondents, and the search for data transmission routes in inter-satellite communication lines. To solve the first problem, an approach based on simulation of the structure of the orbital group is proposed. To solve the second problem, a method is developed that provides a search for routes with the account for current load of communication lines and balancing traffic in general. The lifetime of communication lines between the communication satellites and the respondents of communication sessions is limited by the time spent by the satellites in the radio visibility zones. In this regard, in addition to establishing initial connections, the task of moving the established connections is also considered.
INFORMATION AND MEASURING SUPPORT OF THE AUTOMATED CONTROL SYSTEM FOR METAL BLANKS ANNEALING AND MACHINING SECTION Javanshir F. Mammadov, Gurban S. Abdullayev, Tarana A. Safarova, Igor L. Korshunov
859
Technological operations of production modules and standard active elements of a flexible automated section for annealing and mechanical processing of metal blanks have been investigated. A mathematical analysis based on the use of N-oriented hypergraphs has been carried out. The incidence matrix is determined with the account for functional connections between the active elements in the flexible automated section layout scheme. In accordance with the layout of technical units in a 2-dimensional coordinate system, the main properties of the layout scheme of the flexible automated section for annealing and mechanical processing of metal blanks in a 3-dimensional coordinate system are determined, and a hypergraph scheme is constructed. Based on the layout diagram of unloading the conveyor of the annealing furnace for aluminum billets and loading them onto the conveyor of the production module of grinding machines, the types of sensors for the service industrial robot were selected. An algorithm for the selection of information and measuring elements of the automated control system for the annealing and machining of metal blanks is proposed.

INSTRUMENT-MAKING TECHNOLOGY

METHODS FOR ALIGNING A LASER HEAD ON A NUMERICALLY CONTROLLED MACHINE Aleksey D. Nikolaev, Kirill P. Pompeev, Pyae Phyo Aye
869
Several methods of aligning the laser head installed in the spindle of a CNC machine are described. The principal objective is to ensure precise positioning of the laser head in the operational space of the vertical-milling CNC machine relative to the zero setting of the treated blank. Precise positioning of the laser processing zone in the working space of the machine is an integral step in the process of setting up technological equipment. To solve the set task, the body of the laser head can be adjusted on the machine like the binding of the processing tool using similar technologies. Each of the proposed methods allows positioning the laser processing zone with high accuracy and provides the highest repeatability achievable for the machine. The focus is made on vertical (Z-axis) positioning because linear relocation in this direction forms the focal point on the machined surface. Alignment along other axes is not addressed since it completely repeats the alignment methods of the cutting tool. The alignment methods are multifunctional and can be applied to any vertical machining center regardless of the CNC software.