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


The prospects for using a distributed onboard computer complex as a part of an orbital tether system are considered. The possibilities of using small spacecraft, which are elements of the orbital tether system, are analyzed. The composition of the onboard equipment of the basic and small spacecraft is determined. It is noted that a distributed onboard computer complex must be included in its composition. The structure of onboard computer complex is discussed. As an example of possible mathematical models describing the dynamics of orbital tether system elements, a simplified analytical model of the movement of a small spacecraft in the direction perpendicular to the base orbital plane is given. The use of a distributed onboard computer complex as part of the orbital tether system is shown to expand its functionality in the near-Earth space, improve the reliability and stability of the base spacecraft and associated mini- and microsatellites operation.


The forward and inverse design tasks of an incomplete-drive hopping robot capable of energy-efficient dynamic locomotion are considered. A solution to the direct design problem of simulating a robot in a virtual environment in order to study its behavior and performance is presented. A solution of the inverse design problem is obtained, which consists in the formation of requirements and the search for robot parameters that ensure its best performance. Since simulation modeling does not fully reflect the processes occurring in real life, the design results tested exclusively in a virtual environment cannot fully describe the results of a real experiment and replace them. The results of virtual and full-scale experiments of a prototype of a non-wheel drive jumping robot are compared, and the rationale for the discrepancies in the data obtained is given.


The problem of algorithmic minimization of electromagnetic torque pulsations in a five-phase asynchronous electric drive is considered. The principle of constructing an algorithm for space-vector modulation with a monotonic trajectory of the hodograph of the output voltage vector and an algorithm that makes it possible to reduce the torque ripples in the speed control range of 100:1 by an average of more than two times, and in the region of low speeds by more than ten times compared to the main algorithm currently in use, are proposed. This allows to consider a five-phase asynchronous electric drive as an alternative to a synchronous drive in the tasks of precision control of the movement coordinates. However, at a rotation frequency above half the nominal, resonant phenomena are observed, leading to torque ripples up to 30 %, which requires special measures and can completely exclude the possibility of using such a drive for a number of tasks.


On the basis of computational and experimental studies, topical problems of choosing the most effective tools for determining the wear of materials by the method of artificial bases are considered and solved. The main attention is paid to the problems of ensuring the accuracy, reliability and availability of tools, taking into account the required range of linear and volumetric wear when using friction pairs with constant and variable specific pressure.
OPTICAL FIBER AS A BASIS FOR CREATING SENSORS FOR IDENTIFYING LIQUIDS AND DETERMINING THE CONCENTRATION OF SOLUTIONS Andrej O. Zenevich, Tofig M. Mansurov, Tatiana G. Kovalenko, Evgeny V. Novikov, Siarhei V. Zhdanovich, Tatiana A. Matkovskaia
Currently, sensors based on optical fiber are widely used to control various kinds of objects. Compared with other types of sensors, such sensors have a number of advantages, such as: electrical safety, immunity to electromagnetic influences, the ability to use in combination with optical fibers that transmit data on the state of controlled objects or environments. Fiber-optic sensors are chemically neutral and sufficiently resistant to chemical effects of various kinds, and can also be used to monitor the condition of objects with flammable and explosive liquids. Of particular interest in this regard is the use of such sensors in the chemical and food industries to determine the presence and level of liquids in production containers and measure the concentration of solutions. The possibility of using optical fiber as the basis for sensors for identifying liquids and sensors for determining the concentration of substances dissolved in water is established. Reflectograms of an optical fiber obtained by immersing the end of the fiber in various liquids are analyzed. It is found that magnitude of the peak of the optical fiber reflectogram corresponding to the location of the interface between the core of the optical fiber and the environment, and depends on the refractive index of the liquid in which the end of this optical fiber is located. It is proposed to use the value of this reflectogram peak as an information parameter for identifying liquids having different refractive indices, as well as determining the concentration of substances dissolved in water. The possibility of using an optical fiber in combination with the method of optical reflectometry to create sensors for identifying liquids and determining the concentration of solutions is proved.


NUMERICAL ASSESSMENT OF A DEVICE NOVELTY ACCORDING TO THE INVENTION FORMULA Bushuev Alexander B., Dudarenko Natalya Alexandrovna, Litvinov Yury V. , Mansurova Olga K.
A technique for numerical evaluation of novelty is proposed for two types of technical system models, compiled on the basis of the patent formula of a new solution and a prototype. The first type is a block diagram in the form of a directed graph of the features of the invention. The second type is built as a flow of energy and information conversion from the input of the device to its output. The novelty coefficient is estimated by the degree of asymmetry of the schemes for the prototype and the new solution. The signs of the invention included in the restrictive part of the formula have symmetry. The distinctive part of the formula introduces asymmetry. In the block diagram of the graph, features are ranked by levels, and each level is assigned its own weight. In the information-energy model for the numerical evaluation of physical quantities, the theory of dimensions is used. The resource intensity of values is calculated in the system of kinematic values of Bartini. An example of a numerical assessment of the novelty of a membrane pressure sensor is considered in detail.


In the current conditions, one of the promising areas of research in the IT-domain is the creation and widespread use of integrated decision support systems for proactive management of complex objects based on the integrated coordinated use of digital twins of these objects describing the process of implementing the stages of their life cycle. According to presented analysis, within the framework of such an approach it is possible to find optimal (reference) parameters, programs, and laws of practical management of the complex object, and it may be guaranteed that their robustness and stability can be checked and ensured using data from the digital twin. To date, a large number of digital objects and processes have been developed for various subject areas. However, the processes of creating and using the digital twins of complex objects are synthesized in most cases on a heuristic basis due to the lack of appropriate scientific foundations. It is shown how, using the system-cybernetic interpretation of the processes of managing the life cycle of the digital twin of complex object, it is possible to form a methodological foundation of the corresponding theory. The methodology and technologies for the creation and use of digital twins of complex objects with respect to distributed complexes of cyber-physical systems are described.
Modeling of complex objects is always associated with the solution of problems not only of a methodological, but also of a methodical nature. Such problems include, for example, the problem of the formation and use of the factor space in solving the problem of estimating and predicting the state of the complex object. As part of the problem statement, the main rules are formulated that an expert should use when choosing a factor space for the synthesis of various classes of models, including the example of constructing a fuzzy-possibility model of complex object based on explicit and implicit expert knowledge. An example of constructing a factor space and the corresponding model for a technological process associated with solid-phase roasting of a sulfide concentrate is considered using two fundamentally different approaches to describing this process. These approaches are the classical balance approach and fuzzy-possible approach. On a practical example, it is shown that a reasonable choice of the factor space composition and structure, especially dependent variables (output parameters), plays an important role in achieving the desired result - building a model for estimating and predicting the state of the complex object, which describes the process under study with the required degree of adequacy.
The creation of ships is a complex multi-stage process. There is a need to solve the problems of assessing and analyzing the production potential of the enterprise, as well as the synthesis of technology and operation plans. From the point of view of optimal control, these are problems of assessing the controllability of a complex system and proactive control of its structural dynamics. A method for solving these problems is proposed based on reachability domains for non-stationary deterministic finite-dimensional differential dynamical systems with a tunable structure. As a result of solving the problems under consideration, pessimistic and optimistic estimates of the feasibility of the production program are formed, as well as the optimal technology for implementing the production plan and the work schedule of the equipment of the shipbuilding enterprise.