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

INFORMATION TECHNOLOGIES AND SYSTEMS, COMPUTER TECHNIQUE

199
For a complex system, the problem of refining a priori probabilities of hypotheses about the system state using the data obtained during its experimental adjustment and operation is considered. The proposed method for solving this problem is based on weighted accounting of the results of a priori and experimental studies of the system. The results of comparing a posteriori estimates with estimates obtained by Bayes formulas are presented. It is shown that, in contrast to the Bayesian solution, the use of the proposed method provides for accounting the proximity of the results of a priori studies of the system to the results of experiments, and does not allow a priori information to dominate the experimental data.
206
The frequency properties of a signal modulated by a random process with a nonzero average frequency are investigated. It is shown that the energy spectrum of frequency-modulated harmonic oscillation is infinitely wide and contains a discrete spectral line and a partial region at the frequency of the modulated oscillation, as well as partial regions corresponding to the harmonics of the middle frequency of the modulating narrow-band random signal relative to the modulated oscillation frequency. The spectral regions width depends on the variance and number of the corresponding harmonic of the average frequency of the modulating signal. Results of calculations of the energy spectrum of frequency-modulated harmonic oscillations are presented. It is noted that derived relations for the correlation function and the energy spectrum of the frequency-modulated signal can be used in study and development of information transmission systems with angular modulation of the carrier wave.

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

Improving the Accuracy of Compensation for Nonlinear Elements of Control Systems Dmitry О. Savelyev, Cherny S. P., Vyacheslav A. Solovyov
206
Principles of multi-stage control and methods for compensating for nonlinearities of static nonlinear elements of automatic control systems are studied. Due to the fact that in the case of complex nonlinear elements, compensation using only one of the known compensation methods does not always reduce the system error to the desired value, a new solution is proposed - a compensation method based on the principle of multi-stage control, which almost completely reduces the error to zero. Specific of tuning intelligent systems based on the theory of fuzzy sets to solve the problem of compensating for natural and artificial nonlinearities are described. The influence of various algorithms of fuzzy inference when implementing multi-stage fuzzy control technology to compensate for nonlinearities of various types, is analyzed.

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

222
Principles of development of static and full pressure sensor based on the use of an optical method of information conversion, is considered. A significant novelty of the proposed sensor is the use of optical CCD arrays as secondary converters, with which it is possible to convert the spatial distribution of the light flux into an electric signal. Results of theoretical and experimental studies of information processing procedures are presented, mathematical models and algorithms for microcontroller that provides for measuring linear displacements of the membranes center and processing signals from the output of the photodetector line when exposed to a light spot are presented. The proposed pressure sensor, in comparison with its analogues, has significantly smaller mass and size parameters, and energy consumption is reduced by more than an order of magnitude.
Integrated Endoscopy System for Monitoring Erosion Wear of Steam Turbine Blades Gennady A. Shut, Evgeny I. Puzyrev, Vasilieva Anna V., Vasiliev Alexander S, Nekrylov Ivan S., Artyom K. Akhmerov, Alexander Timofeev
228
The features of video endoscopy system for monitoring working blades of a steam turbine without opening the cylinder body in the operation mode of the turbine unit on a shaft-turning device are considered. The system concept and structural diagram including a flexible and rigid video endoscope, a synchro-sensor and a personal computer, are described. A digital image processing algorithm for calculating blade chords and evaluating the working blades wear dynamics is proposed. The static characteristics of the synchro-sensor are studied using the developed experimental bench simulating the turbine rotor, and the blade chord value is estimated. According to presented experimental data, the error in calculating the blade chord does not exceed 0,2 mm.
An Installation for Studying Optoelectronic Humidity Sensor Nurmamat Umaraliyev, Mahmud M. Matbabayev, Kahramon M. Ergashev
237
An installation is proposed for studying the principle of operation of an optoelectronic sensor for measuring relative air humidity. Description and structure schematic of a device for continuous monitoring of air humidity in a controlled object are presented. A device developed for calibrating humidity sensors, and algorithm for humidity sensors calibration are considered.

TECHNOLOGY OF INSTRUMENT MANUFACTURING

Digital Format for Preparation of Instrument Production. Part I. Design Stage Vyacheslav F. Bulavin, Tamara G. Bulavina, Victor V. Yakhrichev, Alexander S. Stepanov
242
Introduction of digital platforms in the design phase of production preparation at medium- and small instrument-building enterprises is discussed. The process is implemented with the active use of CAD-based and CAE-based products. The tasks performed during design preparation are considered, including 3D design, engineering analysis of the structure, creation of electronic prototypes of product components as one of the factors of digital production. Results obtained in the design solution simulation concerning temperature deformations of measuring instrument units are presented.
Digital Format for Preparation of Instrument Production. Part II. Technological stage Vyacheslav F. Bulavin, Tamara G. Bulavina, Victor V. Yakhrichev, Alexander S. Stepanov
250
The process of introducing innovative digital technologies during the technological stage of pre-production at medium and small instrument-making enterprises is considered. At this stage, a complete package of technical documentation is generated. The program "Vertical" is presented in detail, which provides the possibility of parallel work of process engineers in the design of complex engineering and technological objects in real time. An example of a control program based on a computer-aided manufacturing system is demonstrated; the application allows for visualization of the software product operation.

SCIENTIFIC AND PRACTICAL DEVELOPMENTS

257
An analysis is made of a new class of measurements of thermal quantities, based on the use of multi-valued measures. Using the thermal conductivity of solids as an example, the fundamental fallacy of the proposed approach and the illegality of using the polysemy principle for measures of intense thermophysical quantities are shown. The inconsistency of the declared metrological characteristics of the previously declared method of measuring thermal conductivity with achievable values is proved.
264
A method for evaluating the "production quality factor", developed for calculating the failure rate of radio engineering devices of unmanned automatic space vehicles, is presented. A distinctive feature of the proposed method is accounting for activities regulated not only by normative-technical documentation on the creation, production and exploitation of electronic devices, but also by a system of quality management and applying a structured approach to the development of the questionnaire for subsequent expert assessment of the external and internal audit. It is anticipated that application of formulas derived to obtain a numerical value of the "production quality factor" may increase the accuracy of calculations of the reliability characteristics of radio engineering devices of unmanned automatic spacecraft at the design stage.
Research in Biped Robot Platform Oscillation Islam A. Bzhikhatlov, Gromov Vladislav S.
278
The existing approaches to planning of biped robot motion are analyzes, the advantages and disadvantages of various approaches are considered. A model of biped platform is developed. The model repeats the kinematic structure of the lower human limbs with similar mass-dimensional characteristics and the platform with which the pedipulators are connected via hinges. A simulation model is created in the MATLAB program, which implements the algorithm for the sustainable control of biped robot. During the work, the inverse kinematics problem was solved by the numerical method. Using a control algorithm and a simulation model, the vibrations of the DSHR platform along the vertical axis, as the most critical due to the action of gravity, are studied.