Informatics, computer technology and management. Рубрика в журнале - Siberian Aerospace Journal
On the construction of stress discontinuity lines for a two-dimensional plastic region
Статья научная
The paper considers the plasticity equations in case of two dimensions and the construction of stress discontinuity lines. The construction of stress discontinuity lines is based on the fact that they are located at the intersection point of lines of the same family (characteristics) and are directed along the bisector of the angle formed by these characteristics. Therefore, to find these lines, we constructed characteristics. Such a problem is easier to solve in case of plastic torsion, then there is only one characteristic, it is directed along the normal to the outer contour, and finding the sliding lines and their intersection points is quite simple. Consequently, most of the works devoted to the construction of stress discontinuity lines solve the problem of plastic torsion for isotropic and anisotropic media. For problems of plane strain of plastic ma-terial, this method is not sufficiently developed. This is due to the complexity of constructing sliding lines for such problems and the presence of two families of sliding lines. In this paper, we construct a homotopy of two known exact solutions: that of Prandtl and of Nadai, that is, a continuous transformation of one solution into another. In this case, one can observe the evolution of characteristics that depend on the group parameter a: for a = 1, the characteristics of the Prandtl solution are obtained; at a = 0, the characteristics of the Nadai solution, at a = 0.5, the characteristics of one fami-ly begin to intersect and lines of stress discontinuity appear. These lines are constructed in this paper.
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On the function of time distribution of a complex computing system uptime
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Any space computing complex is a complicated system. A complicated system is understood as a set of functionally related heterogeneous devices designed to perform certain functions and solve problems facing the system. One of the important characteristics of a system is its uptime. This characteristic is often considered to be a random variable. However, such a mathematical model is quite limited, since the uptime depends on many characteristics (parameters) that describe a system. Therefore, the uptime can be assumed to be a continuous random field (that is, a random function of many variables). It is this approach that is used in this work. If there are certain restrictions on the uptime of a computing system, upper estimates are found for the distributions of a random number of system failures. Therefore, the problem of estimating Gaussian field distribution in Hilbert space arises. Two theorems that allow calculating the probability of a Gaussian vector falling into a sphere of a given radius are proved in the paper. The paper is devoted to the reliability of a computing system. The random number of a computing system failures v(r) is a characteristic of its reliability. The v(r) distribution is the distribution of the sum of a computing system random uptime. It is impossible to write down the distribution v (r) explicitly. Therefore, one has to look for an estimate of these distributions from above. Assuming that the uptime of a computing system is the sum of many variables, the authors of the paper obtained the following results: it is shown that the problem of estimating the distributions of a random number of system failures can be considered as the problem of estimating the convergence rate in the central limit theorem in Banach spaces; if there are certain restrictions on the uptime of a computing system, upper estimates are found for the distributions of a random number of system failures. The estimates obtained can be used for further research in the theory of computing systems reliability. Knowing these upper estimates, it is possible to predict the level of average costs for computer systems restoration, as well as for the development of special mathematical and algorithmic support for analysis systems, for management, decision-making and information processing tasks.
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On the location of spacecraft in a given number of orbits
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Space vehicles are an expensive product. For example, just putting such a device into orbit costs at least one hundred million dollars plus the cost of the satellite itself and scientific equipment it carries. However, the cur-rent state of human civilization does not allow us to do without the presence of satellites in orbit. There were 2,062 active satellites in the international database as of March 2019. Compared to 2018, the number of new devices increased by 15 %. Experts warn that in the coming years, the world is expecting a «satellite boom» with a projected increase in the number of devices of about 15–30 % annually. All these satellites are rather different. Currently, several orbits are used for placing satellites on them, depending on the tasks they solve. A geostationary orbit is used for live television broadcasting. Low satellite orbits are used for communication between satellite phones. There are some orbits for navigation systems (GPS, Navstar, GLONASS). Naturally, under these conditions, there is a prob-lem of placing spacecraft over a given number of orbits, with some restrictions on the location of the spacecraft in certain orbits, depending on the purpose of the spacecraft. The solution to this problem is considered on the condition that the number of spacecraft coincides with the number of possible orbits in which they can be placed with some additional re-strictions on the possibility of their placement in orbit. Several solutions to this problem are obtained that allow us to calculate the number of possible combinations for such placement of spacecraft over a given number of orbits.
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One class of solutions to the equations of ideal plasticity
Статья научная
Much attention is given to the study and solution of nonlinear differential equations in the modern mathematical literature. Despite this, there are not many methods for researching and solving such equations. These are point and contact transformations of equations, various methods of separating variables, the method of differential connections, the search for various symmetries and their use to construct solutions, as well as conservation laws. The paper considers a nonlinear differential equation describing the plastic flow of a prismatic rod. A group of point symmetries is found for this equation. The optimal system of onedimensional subalgebras is calculated. Conservation laws corresponding to Noetherian symmetries are given, and it is also shown that there are infinitely many non-Noetherian conservation laws. Several new invariant solutions of rank one, i. e. depending on one independent variable, are constructed. It is shown how classes of new solutions can be constructed from two exact solutions, passing to a linear equation. Thus, in this short article, almost all methods of modern research of nonlinear differential equations are involved.
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Статья научная
Currently, the development of large-sized space structures and, in particular, transformable reflectors is actively developing. A feature of these devices is a small volume during transportation and large dimensions in the expanded working condition. Therefore, it is important to carry out a reliable and smooth deployment, adjust the shape of the active radio-reflecting surface with a given accuracy, and adjust the orbital position. In outer space, the system is constantly exposed to radiation, there is a large temperature difference in near-Earth orbit, there is a solar wind, which mainly affects the radiation pattern. In this paper, the process of deployment of the reflector spokes in the presence of disturbances and measurement errors is considered. The solution to the problem is presented using the separation theorem. To estimate the parameters of the system in the presence of measurement noise, the Kalman filter is applied. Its performance is shown at various values of the noise intensity. A random process such as white noise was selected as external disturbances and measurement noises. The control problem is solved using the optimal control algorithm according to the hierarchy of target criteria. The possibility of minimizing energy costs by means of interval switching on of measuring sensors is shown. The results of numerical simulation are presented.
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Optimization control actions for the electrolytic method of aluminium production
Статья научная
The most common indicator of the aluminium production process managing efficiency is the cost of the metal production, but this concept includes a lot of components. First, this is the cost of raw materials and electricity in this region, as well as the labour cost per ton of products, consumption coefficients of raw materials and energy, capital costs for construction and repairs, waste disposal cost, environmental payments, etc. At the same time, there is no single functional of the process quality, depending on technological parameters, that is, the problem of complete and relatively strict mathematical process optimization as a whole is currently not solvable, not only because of its volume, but because of the lack of a complete efficiency model. In this study, particular efficiency criteria are considered, the improvement of which is aimed at the optimization model of control actions developed by the authors, which are selected based on the possible levers of the current automated process control system (APCS) for aluminium electrolysis. All tests were carried out on Virtual cell software without transfer to a real control object.
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Optimizing the readability of tests generated by symbolic execution
Статья научная
Taking up about half of the development time, testing remains the most common method of software quality control and its disadvantage can lead to financial losses. With a systematic approach, the test suite is considered to be complete if it provides a certain amount of code coverage. At the moment there are a large number of systematic test generators aimed at finding standard errors. Such tools generate a huge number of difficult-to-read tests that require human verification which is very expensive. The method presented in this paper allows improving the readability of tests that are automatically generated using symbolic execution, providing a qualitative reduction in the cost of verification. Experimental studies of the test generator, including this method as the final phase of the work, were conducted on 12 string functions from the Linux repository. The assessment of the readability of the lines contained in the optimized tests is comparable to the case of using words of a natural language, which has a positive effect on the process of verification of test results by humans.
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Статья научная
The article proposes an approach to developing the architecture of a service-oriented information processing system, modeling and process control. The system, which is being developed, is a tool for identifying, predicting and controlling discrete-continuous processes. Its mathematical apparatus is based on nonparametric algorithms of identification and control. The software architecture includes the following main modules: the module for processing data, modeling and forecasting output process variables and the process control module. The first module includes data preprocessing algorithms: normalization, centering and analysis of outliers and omissions. The modeling module is an algorithm for research and recovery dependencies between process variables, process identification using nonparametric estimation of the regression function from observations. The last module is an implementation of nonparametric dual control algorithms. Control devices built on the basis of these algorithms perform functions of both object control and its study. The article discusses the application of architectural solutions based on two proven approaches in the field of software development: the composite approach and the service- oriented approach.. The main principles of composite architecture as a set of software systems with many characteristics that perform a specific task and service-oriented architecture as a modular approach to software development are described. The advantages of the applied composite service-oriented architecture over other variants of software architecture for control systems are shown, in particular, monolithic software architecture is compared with composite service-oriented architecture. This means that a researcher can use a single operation, which is a logically isolated, repeated task related to the production process of the enterprise. At the same time, it is necessary to ensure positive results when integrating with existing software products of enterprises which greatly complicates and requires the development of new components, as well as support for the "inherited" parts of the system.
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Piecewise approximation based on nonparametric modeling algorithms
Статья научная
In this research the issue of inertialess processes modeling is under study. The main modeling algorithm is the non-parametric recovery algorithm of the regression function. The algorithm allows to build a process model under conditions of low a priori information. This feature may be particularly important in modeling processes of large dimensions prevailing in the space industry. One important feature of the algorithm for nonparametric estimation of the regression function is that the accuracy of modeling using this algorithm highly depends on the quality of the observations sample. Due to the fact that in processes with large dimensions of input and output variable vectors observation sampling elements are in most cases unevenly distributed, the development of modifications to improve the quality of mod-eling is relevant. The modification of the nonparametric dual algorithm based on piecewise approximations has been devel-oped. According to the proposed modification, the process area is divided into sub-areas and a non-parametric esti-mate of the regression function for each of these sub-areas is recovered. The proposed modification reduces the impact of some observation sampling features, such as sparseness or voids in observation samples on the quality of the built model. The computational experiments were carried out, during which a comparison was made between the classical algorithm of non-parametric estimation of regression function and the developed modification. As the computa-tional experiments have shown, with uniform distribution of the sample elements of observations, the developed modification does not lead to the improvement of the quality of modeling. With a substantial uneven distribution of the observations sample elements, the developed modification resulted in a 2-fold improvement in the quality of the simulation. The results suggest that the proposed modification can be used to model complex technologi-cal processes, including those in the space industry.
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Статья научная
Inspection of underwater objects, such as underwater archaeological sites, sunken technical objects, and un-der water located technical structures, requires the use of specially trained divers, manned or unmanned, re-motely operated or autonomous underwater vehicles. A relatively rarely used design for such underwater vehicles is a design in the form of a quadrotor with posi-tive buoyancy. This article discusses the design and the control system of the remotely operated underwater vehicle in the form of a quadrotor. The aim of the work is the selection and justification of the shape of the vehicle, the selection of the optimal structure of the control system with the expectation of the subsequent use of the vehicle as an au-tonomous one. The potential advantages of the selected design in the form of a quadcopter with a cylindrical body are de-scribed, in particular, the large volume of the sealed space of the vehicle, the possibility of installing capacious power sources, the potential for stabilizing the vehicle in a given position if there is a current at the place of work. The sealed case of the device is designed to place control electronics, power electronics and battery power of the device. The selection and justification of the shape of the sealed enclosure were made using a hydrostatic modeling apparatus and theoretical mechanics. A solid cylinder made of polycarbonate was selected as a form of the sealed housing of the vehicle. The advantage of the selected form in comparison with the parallelepiped-shaped case is shown under the condition of the same material parameters. The control system of the device includes software and hardware components. The choice of hardware com-ponents is justified, their key characteristics are described. As the control device of the top level, a single board computer (SBC, Single Board Computer) Orange Pi PC was selected, the direct control of the motor of the vehi-cle is performed using the Cortex-M3 microcontroller. The software architecture of the device is described. The choice of architecture is determined by the requirements of poorly connected components (which makes it easy to replace particular software elements without the need to modify the other elements), the simplicity of the potential replacement of the top-level control modules (which potentially allows switching from a remote control model to an autonomous control model). Some software components are described. The control system is implemented with the high-level lan-guage Python version 3.7, the basis of the control mechanism is message passing, the MQTT protocol maintained by the Mosquitto server is selected as a messaging mechanism. Testing of the vehicle was carried out in pools with standing water and with a simulated current. Testing showed the need to gain experience to control the underwater vehicle. The study will allow us to further develop a new version of the underwater vehicle, taking into account the wishes and identified problems.
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Статья научная
Today, there are many approaches to developing parallel programs. It is considered that it is more efficient to write such programs for a particular computing system. The article proposes to ignore the features of a particular computing system and outline plans for the development of a certain automated system that allows trying to improve code efficiency by developing programs with unlimited parallelism, as well as explore the possibility of developing more efficient programs using the restrictions imposed on maximum parallelism. This approach was demonstrated on the example of the analysis of various matrix multiplication algorithms. As a mathematical apparatus, the study considered various approaches to the description of algorithms to increase their implementation, including an approach based on unlimited parallelism and, also, an approach based on various restrictions on parallelism is proposed. In the course of the work, sequential and parallel methods of matrix multiplication were studied in detail, including tape and block algorithms. As a result of the study, various matrix multiplication methods (sequential, with left and right recursion, parallel methods) were studied and more effective ones were found in terms of the resources used and the restrictions imposed on parallelism. A sequential method and a cascade summation scheme were analyzed and proposed as possible ways of convolving the results of solving the problem obtained after the decomposition stage. Also, a number of programs with different levels of parallelism were developed and implemented in the functional-stream parallel programming language. In the future, such transformations can be carried out formally, relying on a knowledge base and a language that allows equivalent transformations of the original program in accordance with the axioms and algebra of transformations laid down in it, as well as replacing functions that are equivalent in results and have different levels of parallelization. These studies can be used to increase the efficiency of developed programs in terms of resource use in many branches of science, including in the field of software development for the needs of astronomy and rocket science.
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Saint-Venant and Karman equations for an orthotropic pre-stretched plate under tem-perature
Статья научная
Thin plates that are preliminarily stretched with the help of forces in their plane and attached to rigid ribs are used in space technology. In fire rescue technology, plate designs are being developed that repre-sent a life net supported by drones to cancel the energy of a person falling from a height during his evacua-tion both from a high-rise object and in other exceptional cases. The plates are thin and usually consist of a composite material. Shear forces predominate as loads; to reduce deflection, the life net is pre-stretched onto a rigid contour. In this work the equations of B. Saint-Venant and T. Karman for an orthotropic plate are obtained, tak-ing into account the temperature increment. The former are the equations of equilibrium in displacements with initial forces, and the latter are a system of non-linear equations of deformations continuity and non-linear equations of equilibrium. The form of models’ representation is differential. Examples of plate calculation for the action of a concentrated force and preliminary stretching are con-sidered. The plate continuum is replaced by a discrete region; differential ratios are replaced by finite-difference analogs. Nonlinear equations were solved by iterations. The calculation of a thin plate for the action of a concentrated force showed that the resulting longitudinal forces are so large that the stresses are two to three orders of magnitude higher than the stresses allowed for the considered orthotropic material. To reduce stresses, the plate is pre-stretched. The bending surface be-comes more monotonous, the deflection decreases, which leads to a decrease in the stress level. Comparison of calculations obtained from the action of a concentrated force and temperature changes showed that in this flexible plate of small thickness, the effect of temperature exposure is insignificant. The apparatus of the Karman theory is relatively complex in numerical implementation. The mixed form of the model in stresses and displacements requires additional studies of the convergence of solutions. The Saint-Venant deformation model as a model of a flexible plate with a small deflection makes it possible to solve the problems of ensuring the rigidity and strength of a complex longitudinal-transverse bending of orthotropic plates.
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Savostyanova I. L. 3-dimensional solutions from two variables
Статья научная
In this paper, we consider stationary 3-dimensional equations of ideal plasticity with the Mises flow condition. The material is assumed to be incompressible. The case when all three components of the veloci-ty vector and hydrostatic pressure depend only on two coordinates x, y is studied in detail. For this case, a new name is introduced – 3-dimensional solutions from two variables, to distinguish it from the generally accepted two-dimensional state, when only two components of the velocity vector and hydrostatic pressure differ from zero. It is proved that the system admits, in the sense of S. Lie, a Lie algebra of dimension 10. It is shown that all 3-dimensional solutions from two variables is a superposition of the plane stress state and plastic torsion around the z-axis. Two invariant solutions of the equations describing the 3-dimensional deformed state are constructed. The first solution can be used to describe plastic flows between two rigid plates that approach at different speeds. The second solution is used to describe the stress-strain state of the material inside a flat channel formed by converging plates.
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Search for broadband signals ground-based radio navigation system
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In the present paper, a method of temporary search for broadband of frequency manipulation with minimal shift keying (MSK) signals of ground-based radio navigation systems (RNS) is considered. The method is based on a multi-alternative optimal signal detection (the signal may belong to one of the orthogonal signals) using the evaluation-correlation principle of processing (ECPP) under conditions of a priori uncertainty. The problem of representing broadband MSK signal as a signal with double discrete frequency-phase modulation (FPM) was solved. The law of phase manipulation in the form of a binary sequence of elements lb of a length code τ э L (in the “Sprut” RNS, 16383 L , 2.5 э mcs is the duration of the signal element) is defined through the law of frequency manipulation in the form of a binary sequence of elements ld of a known length L code. The representation of the signal in the form FPM allows, during correlation processing, to replace the correlation integral on the interval [0, τ]э L by L the sum of correlation integrals on the intervals [0, τ]э or by L the sum of element-by-element correlations. The calculation of element-by-element correlations allows the use of a matrix apparatus for the ECPP of the analyzed signal. With the technical implementation of the “search” procedure, there is no need to form 2L pairs of reference quadrature signals with the length L of the modulating code, and instead of that a pair of element-by-element correlations is memorized and over time τэ , according to a code element lkd , cyclically shifted by 1 k elements, frequency manipulation and a code element klb , cyclically shifted by 1 k elements, phase manipulation, block-by-block accumulation L of quadrature correlations is performed. The use of upper-left and lower-right triangular matrices with binary elements klb makes it possible to search for broadband MSK signal with additional phase manipulation of a discrete information message. The structure of the optimal algorithm of parallel search for ECPP of the broadband MSK signal with the use of a matrix apparatus, which allows to implement the optimal algorithm “of search” during the duration τэ L of the signal in real time.
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Semi-analytical method for calculating elastic-hydrodynamic contact
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A semi-analytical method for calculating elastic-hydrodynamic contact based on the partial use of Computer Aided Design / Computer Aided Engineering (CAD / CAE) packages and solutions of the integral equation of functional relationship between pressure and deformation have been described. The pressure in the lubricating layer is described by solving the modernized Reynolds equation taking into account the factors such as elastic deformation of surfaces in the contact zone, cavitation effect in the low-pressure region, and variable viscosity of the lubricant layer, which depends on thermodynamic parameters. Based on the stationary solution, a tensor damping coefficient has been obtained, with the help of which calculations of transient non-stationary modes that occur in cases of a sharp change in the external load have been further performed. A comparison of the results of modeling a plain bearing obtained by using the proposed semi-analytical method has been made and the full calculation performed using CAD / CAE programs such as ANSYS and COMSOL Multiphysics. The comparison showed good convergence of all numerical methods. At the same time, the “hybrid” method showed a number of advantages over direct calculations in CAD / CAE packages, such as: faster calculation speed, low requirements for computing resources and accounting for the cavitation effect. The described semi-analytical method allows to create digital twins of bearing units, centrifugal pumps and hydraulic supports used in satellite cooling systems and in rotary mechanisms of ground-based satellite dishes.
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Simulation computer model for virtual research of optoelectronic measuring systems
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The paper considers a simulation computer model of an optoelectronic system for measuring the point objects coordinates. The model allows optimal coordination of the system links parameters in order to minimize the measurement error. The method of multiple statistical tests which allows accumulating the results of single computational experiments for each specific measurement event with a unique random distribution of links parameters and characteristics, and then carrying out statistical processing of the accumulated results is the main method of computer simulation. As a result of multiple analyses, multi-parameter functional dependencies that provide optimal coordination of parameters controlled by the designer or operator according to the criterion of the resulting measurement error minimizing are realized. The article presents the results of evaluating modeling parameters that reduce the measurement error. It is relevant to apply this method when using the same measuring system in different operating conditions, for different measured objects and when performing various functional tasks since it allows adapting the system for a specific application. The model presented in the article can be concretized for the purpose of evaluating and multi-parameter optimization of particular object parameters, as well as for developing a virtual measuring stand on the basis of the model and its modifications.
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Статья научная
The implementation of efficient communication systems with high data transfer rates requires the usage of signals with a high modulation order. Current trends in the development of communication systems are aimed at orthogonal frequency multiplexing of signals (OFDM – Orthogonal Frequency Division Multiplexing) usage, which allows you to flexibly change the data transfer rate, to reduce the frequency resource by improving spectral efficiency, as well as to combat frequency-selective fading and selective interference. However, the price of such a solution is also high. The high peak-to-average power ratio (PAPR) OFDM signals imposes a requirement for the linearity of the analogical path, significantly reducing the efficiency of the transmitter and receiver output amplifiers, increasing the dimensions and power consumption of the communication system as a whole. The practical novelty of the work lies in the possibility of using the developed method for reducing the PAPR factor in systems with complex communication channels, such as troposcatter and near-field magnetic induction communication systems, where significant effect of selective interference, intersymbol interference, and frequency-selective fading is present. The results of this work give the opportunity to navigate a large number of algorithms for reducing the peak factor of OFDM signals and apply the desired algorithm in a specific task.
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Статья научная
Obtaining electricity from renewable energy sources is primarily due to the exhaustion of traditional natural energy sources, such as coal, oil, gas. Today it is a promising area of development. The adverse impact on the environment of the use of traditional energy technologies is well known and scientifically proven. The use of traditional technologies inevitably leads to climate change, so the topic of the transition from traditional to alternative energy sources is undoubtedly relevant. Using of solar power plants with photovoltaic modules recently has gained relevance. However, the efficiency of such installations depends largely on their correct orientation to the Sun: the more precisely the system is installed, the more energy it will be able to convert. This article presents the results of the development of a simulation model of the solar panel orientation control system. To maximize the production of solar energy, the control system with tracking the Sun is built using fuzzy logic: fuzzy rules are formulated to control the positions of the object relative to the vertical and horizontal planes. The use of fuzzy logic is based on the product model of knowledge, which implies the use of linguistic variables to avoid the limitations inherent in classical product rules. The use of fuzzy control allows to correct the movement of the panel in the shortest time in the autonomous mode, thus reducing the arising power losses. Russian SimInTech dynamic simulation environment for technical systems is used as the system development environment. Simulation model is represented by several subprojects, united in a single database. The system model is implemented using standard blocks and a set of submodels, as well as a programming unit. The result of the work can be tracked in the 3D module of the built-in visual editor, which allows you to display the interaction of three-dimensional models objectively. In order to simplify and more finely implement the work of the project, a system of loading data, sunrise and sunset points, from an external Excel file was used.
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Software system for mathematical simulation of the electronic beam welding process
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Within the framework of this study, a software system for modeling the distribution of the temperature field in the steady-state mode of the electron-beam welding process for thin-walled aerospace structures is proposed. The purpose of creating such a software system is to improve the quality of control of the electron-beam welding process and, accordingly, to reduce the number of defects in welded joints of thin-walled structures. The software system has a model structure and implements the energy distribution models proposed earlier by the authors. The MySQL database management system and the Embarcadero RAD Studio programming system were chosen as the means of implementing the program. The central link of the system is a database that allows you to store and process information both on mathematical modeling and on the results of simulation and field experiments. The article describes the structure of the developed software system, and also presents algorithms for the operation of its constituent modules. The system provides the user with the opportunity not only to carry out simulation according to the specified technological parameters (welding speed, accelerating voltage, beam current, boundary conditions, simulation time, product material), but also to visualize the results and save them in a single database. The use of the proposed system allows not only to minimize the costs of the enterprise for the development of technological parameters of the steady state for the electron-beam welding process, but also to create a flexible information base for collecting experimental information with the aim of further automating and intellectualizing the technological process of creating permanent joints in the framework of Industry 4.0.
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In this paper, we consider the solution of the filtering problem using the Kalman filter with the optimal tuning of the radio-reflecting net. A large-sized transformable space-based reflector is considered. In the process of this structure placing in orbit, it is possible that the real form of the radio-reflecting net can deviate from the desired one. To ensure point-to-point adjustment of the active part of the mesh, a cable-cable system is used. The nodal points of the radio-reflecting surface are connected to the back side of the net through cables. They have built-in actuators that allow one to change the length of the cables. A piezo actuator was selected as a control device. By point-by-point adjustment of the piezo actuators the net is stretched to the required shape. This ensures a high-quality radiation pattern and a high signal level when receiving and transmitting data. Specific values of the disturbing influences are given. To measure the supply voltage on the piezo actuator and the cable length, a voltage converter and a laser scanner are used. Possible deviations from the calculated initial position are determined. In accordance with the principle of separation, the estimation problem is solved first, then the control problem. The estimation problem is solved using the Kalman filter. The control problem is solved using the optimal control algorithm according to the hierarchy of target criteria. The results of numerical simulation are presented. The successful solution of the problem is shown with variable values of measurement noise and disturbing influences. Comparison with trajectories obtained applying various optimal control algorithms is given.
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