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

INFORMATION TECHNOLOGIES AND SYSTEMS, COMPUTER TECHNIQUE

777
A method for determining information packets source in systems using communication protocols that do not allow generating messages longer than 10—15 bytes, is described. The method is based on determining whether a particular received packet belongs to a structured set of fixed size packets associated with the source. To identify the ownership, each information packet contains a hash sequence field formed on data from other packets of the source and the source unique numeric identifier. As a result of analysis of this sequence and sequences of other information packets, the receiver generates a set of packets that form a single source message and determines location of each packet in the message. Using the probability theory and the theory of random processes, numerical characteristics of the probability of occurrence of error in determining the packet generated source are derived. The error probability dependences on the information packet generating algorithm parameters — the hash field length and the power of the analyzed set of information packets — are obtained. Applicability of the method for separating messages from multiple sources is demonstrated, and the dependencies between the hash field length and the number of message sources are formulated.

INSTRUMENTS AND SYSTEMS OF AUTOMATIC CONTROL

786
794
Two methods for selecting the transfer function of a discrete correction filter are considered. With a simpler method, the control effect is significantly reduced, but the speed error increases. A more complex method of correction filter selection enables the speed error retention, as in the case of minimum damping time of the free process, but with a less significant reduction in the control effect and a small overshoot when working out the jump. An example of digital tracking system calculating is given. Numerical simulation of the calculated CSR in the MatLab system is performed for linearly increasing and stepwise reference signals. The simulation data are reported to coincide with the calculated results.
803
The task of synthesis of an algorithm for control of terminal maneuver of aircraft–type UAV landing on a mobile platform is formulated and accomplished by the method of reverse dynamics problems using the principles of flexible kinematic trajectories and pointing to the landing point. Results of the synthesized control algorithm for the landing maneuver of the UAV Aerosonde testing in the MATLAB environment for various wind disturbances are presented.
786

OPTICAL AND OPTO-ELECTRONIC INSTRUMENTS AND SYSTEMS

STATIC AND FULL PRESSURE MEASUREMENT SYSTEM USING INITIAL SIGNAL SPLITTING AT THE SECONDARY CONVERTER INPUT Ruslan A. Borisov, Ivan V. Antonets, Alexey А. Chertoriyskiy, Alexander V. Krotov
813
Pressure sensors are widely used in aircraft to measure the static and full pressure of the oncoming air flow as a primary information in on-board air signal systems. In the data system, the measurement results are recalculation automatically to determine the flight altitude, speed, true air speed, Mach number, and vertical speed, according to well-known algorithms. A sensor of the full and static pressure with elastic membrane sensing element is presented. The membrane deformation is measured by an optical system, consisting of radiation source and position-sensitive photodetector based on the photo-detector line, installed opposite each other, with a curtain attached to the membrane center and placed between them. The membrane deformation displaces the optical spots formed on the photodetector surface by the passed through slits in the curtain. A novelty of the proposed sensor consists in the use of splitting of the initial information achieved by application of shutter with n slits forming n light spots on the photodetector, and these spots are displaced depending on the change in the measured pressure. Thanks to this innovation, it is possible to obtain n independent values of the measured pressure for one cycle of sensor line polling and to increase the measurement accuracy by averaging the results. The absence of additional elements on the curtains (emitters and light detector) improves the dynamic characteristics of the sensor. The proposed solution made it possible to minimize the influence of external disturbing factors (in particular, the aircraft vibrations) and to increase the accuracy and speed of the pressure sensor. Experiments carried out using a laboratory facility have confirmed the high level of the pressure sensor metrological performance.
DISC RESONATORS FOR ANGULAR VELOCITY SENSORS Elena А. Vyuzhanina, Viktor V. Krishtop
823
Disc and ring resonators are used as sensitive elements in angular velocity sensors. The sensitivity, or minimum detectable angular velocity is determined by the quality factor of the resonator. An approach is proposed for implementation of new types of gyroscopes based on disk mini-resonators with whispering gallery modes is proposed, and characteristics of two samples of passive disk resonators with a diameter of 5 mm, made of CaF2 and MgF2, are determined theoretically and experimentally by analyzing the resonance curve. The quality factor obtained from experimental data comprises about 5·108 and coincides with the theoretical result. The derived estimate for minimum detectable angular velocity Ωmin = =0.3°/h allows to use such gyroscopes with whispering gallery resonators in a wide range of different devices, e.g., robotics, drones, etc.

INSTRUMENT-MAKING TECHNOLOGY

APPLICATION OF MACHINE VISION IN THE TASKS OF AUTOMATIC POSITIONING OF MODULAR EQUIPMENT TOOL Afanasiev Maksim Ya , Fedosov Yury V , Krylova Anastasiya A., Shorokhov Sergey A.
830
Modular equipment is characterized by versatility in use and can perform processing operations as well as supporting ones. It is obvious that modules can vary in size and in the tool axis position, which makes it difficult to install and configure in manual mode. A technique for automated positioning of removable modules for a three-coordinate platform based on the use of a computer vision system is proposed. An algorithm is developed that combines an observing camera located above the working area with incremental encoders of the platform servo drives. A library of optical labels is used to determine the configuration of the workspace and the dimensions of the module. This technique allows to avoid the error of manually installing modules by comparing the coordinate systems of the module and the platform, as well as to increase the level of automation of the product workflow.
INDUSTRIAL CYBER-PHYSICAL PLATFORM FOR SMALL SERIES PRODUCTION OF POLYMER PARTS Artemiy V. Chukichev, Timofeeva Olga S., Yablochnikov Yevgeny I.
840
An approach to the creation of an information technology platform for conducting research on organization of production processes using technologies of industrial cyber-physical systems is considered. The process of technological preparation of the products production with injection molding machines using replaceable polymer forming parts made by additive installations is presented. Possibilities of improving physical production processes by using information obtained by monitoring of the production system objects are analyzed. The necessity of using systems for simulation modeling of technological processes and the possibility of their development by collecting and analyzing digital data at all stages of production preparation are noted.

SCIENTIFIC AND PRACTICAL DEVELOPMENTS

847
The type of optical absorption gas analyzer for monitoring freons concentration in the air is specified. Characteristics of the gas analyzer to be developed are determined. A functional flow diagram of the optical absorption gas analyzer is presented. A method of modulating the pressure of the analyzed gaseous medium in the working chamber is developed and analyzed. A system of interference filters for the analyzer is designed.

BRIEF NOTES

METROLOGICAL ASPECTS OF MATERIAL HARDNESS MEASURING BY THE METHOD OF DYNAMIC INDENTING Irina A. Kashapova, Fedorov Alexei V, Mikhail V. Kuzmichev
857
The problem of application of hardness measurements based on the dynamic indentation approach in the Russian Federation is reviewed. Metrological aspects of using the dynamic indentation method to control the hardness of materials are discussed. Principles of the hardness measurement method are described. Metrological support of the dynamic indentation method is considered and recommendations for the method improvement are formulated.
862
The problem of modernization of the system for control over the fuel combustion efficiency is considered. The necessity for the system to be adapted to conditions of aggressive environment of the boiler house is substantiated. The modernization is anticipated to provide a reliable data on an ongoing basis, to simplify equipment operation and relieve the operators having to perform their own calculations. The stages of the proposed modernization are described briefly. Modern methods of measuring the parameters of fuel combustion efficiency are taken as a basis, sensors capable of operating in difficult conditions of a boiler house are investigated, a structural-functional diagram and an algorithm of a modernized system of fuel combustion control by the main channels for measuring concentrations of flue gas components are proposed. Improvement of built-in combined intelligent gas analysis systems is predicted to significantly improve the characteristics of the system for monitoring the efficiency and quality of fuel combustion.