Mathematics. Physics. Mechanics |
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Gidaspov V. Y.
Development of the physico-mathematical model of the process, computational algorithms and program complex for simulation of combustion and detonation of combustible mixtures, consisting of particles of metals and air. The calculation of the fine structure of stationary waves, combustion and detonation, determine the ignition delay minimum speed of detonation and the maximum speed of burning.
Physical and mathematical model, numerical algorithms and complex of the programs for calculation of stationary waves of ignition and detonation in a combustible mixture of magnesium particles from the air, which can be used in the modelling of multi-dimensional currents.
The numerical modeling of stationary waves of burning and detonation in the standard terms in respect of the initial mass of magnesium and air in the range from 0.03 to 2. Calculations of the stationary waves of combustion and detonation structure, including heating, melting, evaporation, inflammation and composition change of particles and the corresponding change f the temperature and composition of gas-phase products of combustion, forming of magnesium particles, magnesium oxide and nitride magnesium. The effect of a mass fraction of magnesium at a minimum rate of fixed detonation, and the maximum speed of the stationary combustion wave.
Сalculations, which show that the parameters of the stationary waves of burning and detonation of an asymptotically tendency to the equilibrium point to the equilibrium adiabat.
The developed numerical algorithms and computer software can be used for the design of advanced propulsion systems, as well as study of the combustion and detonation parameters of fuels which are composed of dispersed particles of metals.
Keywords: numerical simulation, metallized fuel, chemical reactions, phase transitions, combustion, detonation |
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Bezglasnyi S. P., Khudyakova M. A.
The necessity to realize of the set motions and orientation of satellites and spacecraft in orbit requires the development of a mathematical theory of control and new algorithms of control. Work is devoted to the active control of randomly set of the spacial motions of a satellite-gyrostat variable structure relative to its center of mass.
The main purpose of this work is analytical construction of active external program and stabilizing controls to ensure the stability randomly set of program motions of a satellite-gyrostat.
A satellite-gyrostat variable structure is simulated by a system of two co-axial solids with moments of inertia which depend on the time. The equations of motion of the system are displayed in the form of the Lagrange equations of the second kind. Program control is constructed as solution of the inverse problems of dynamics; stabilizing control is synthesized on the principle of feedback. The property of asymptotic stability of motions was proved on the basis of Lyapunov's direct method of classical stability theory by using the method of limit functions and limit systems, allowing to build and apply Lyapunov's function having constant signs derivatives.
In this work the equations of a spacial motion relative to the center of mass of a balanced gyrostat with variable structure are derived. Active control attached to the satellite-gyrostat to realize the manifold of its randomly set program motion in orbit is received. Stabilizing control which ensuring the property of asymptotic stability realized motion is synthesized.
Results which were received in this work are develop and generalize the corresponding results in area of a control of the gyrostat’s motion in two directions: firstly, Lyapunov’s function having constant signs derivatives allows to build control is much easier without the terms of the third order of smallness of the variation; secondly, this problem was solved for the gyrostat with variable moments of inertia in the first time. Results of work can be used for the design of systems of active control of the satellites-gyrostats in orbit.
The necessity to realize of the set motions and orientation of satellites and spacecraft in orbit requires the development of a mathematical theory of control and new algorithms of control. Work is devoted to the active control of randomly set of the spacial motions of a satellite-gyrostat variable structure relative to its center of mass.
The main purpose of this work is analytical construction of active external program and stabilizing controls to ensure the stability randomly set of program motions of a satellite-gyrostat.
A satellite-gyrostat variable structure is simulated by a system of two co-axial solids with moments of inertia which depend on the time. The equations of motion of the system are displayed in the form of the Lagrange equations of the second kind. Program control is constructed as solution of the inverse problems of dynamics; stabilizing control is synthesized on the principle of feedback. The property of asymptotic stability of motions was proved on the basis of Lyapunov's direct method of classical stability theory by using the method of limit functions and limit systems, allowing to build and apply Lyapunov's function having constant signs derivatives.
In this work the equations of a spacial motion relative to the center of mass of a balanced gyrostat with variable structure are derived. Active control attached to the satellite-gyrostat to realize the manifold of its randomly set program motion in orbit is received. Stabilizing control which ensuring the property of asymptotic stability realized motion is synthesized.
Results which were received in this work are develop and generalize the corresponding results in area of a control of the gyrostat’s motion in two directions: firstly, Lyapunov’s function having constant signs derivatives allows to build control is much easier without the terms of the third order of smallness of the variation; secondly, this problem was solved for the gyrostat with variable moments of inertia in the first time. Results of work can be used for the design of systems of active control of the satellites-gyrostats in orbit.
Keywords: gyrostat, program motion, functions with a constant sign, Lyapunov's function, asymptotical stability |
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Kurennov S. S.
This article is dedicated to the development of the method of calculation of adhesive joints. Here is proposed to model the adhesive layer with a two-parameter model of the elastic foundation.
Here is given an analytical model for calculation of the stress-strain state of a three-layer beam. Connecting layer is simulated by the two-parameter elastic foundation, bearing layers are considered as the beams of Timoshenko.
The problem is reduced to a system of differential equations which is solved by matrix method.
The new model of the adhesive joint allows more accurate simulation of the stress state in the neighborhood of the boundary points of the connection, in the most loaded areas.
The technique, proposed here, can be developed for a multi-layer joints.
To determine the stress state of the adhesive joint here was used a multi-parameter Vlasov-Pasternak elastic foundation model, which takes into account the relative shifts of the layers and their derivatives.
Keywords: single lap joint, analytical solution, adhesive joints, Timoshenko beam |
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Kasumov E. V.
The purpose of this paper is stepwise development of complex of nonlinear mathematical models of design and checking calculations of aircraft mechanical systems.
The paper discusses techniques of numerical simulation using the finite element method for early stages of mechanical system design for aircrafts.
Mathematical models of kinematic and power analysis of mechanical system with flexible links are considered as a basis for determination of preliminary data of design parameters calculation of links including the load-bearing surface.
This paper concerns issues of determination of preliminary endurance of aircraft mechanical system elements at early stages of design thereof. The technique of design calculation is built on usage of numerical methods for determination of load amplitude spectrum.
Examples of calculation of load-bearing surface made of composite materials, lightweight helicopter control system mechanisms are presented. Application possibilities of nonlinear problems solution at initial stages of aircraft development are examined.
The obtained function of face panels thickness is determined as a rational function of material distribution in design calculation at preset field of loads and temperatures.
Approaches to calculations of structure rational parameters are considered with which the most smooth and level low stress field is obtained. This allows enhancing fatigue strength characteristics. On the basis of calculation results the determination of preliminary endurance for idealized structure of aircraft assemblies is performed. Main assumptions in preliminary endurance calculation are a uniformity of material properties, surface smoothness, and absence of processing defects. Results of tests of laboratory patterns of materials used in the structure are utilized in source data.
Mathematical models for design calculation of load-bearing surface made of composite materials are intended for determination of rational values of maximum stiffness.
Component simulation of forthcoming bench and flight testing on the stage of flying vehicle designing allows to increase efficiency of full-scale test as well as to define optimal design parameters more precisely.
Keywords: the mathematical model, numerical simulation, kinematic analysis, power analysis, designing |
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Myint Z. M., Khlopkov A. Y.
To create a useful engineering program for determination of main aerodynamic characteristics of complex-shaped bodies in rarified atmosphere. The program should provide for sufficiently short calculation time to be applied at early stages of high-speed vehicle design. To determine the main aerodynamic characteristics of reentry vehicles in rarified atmosphere on all segments of their trajectories – from orbital flight to landing on Earth.
Cognitive approach in computer science is a combination of methods; algorithms and software used for modeling the cognitive abilities of the human brain to solve specific application problems. Numerical methods are considerably complex, which makes it difficult to apply them at the preliminary design stage when a lot of options are considered. Therefore, models, which are based on cognitive approach, become useful. They are built on the basis of scientific and intuitive analysis of data obtained by means of theoretical, experimental and numerical studies. Even specialized computer systems such as Knowledge Based Engineering are created to reduce project time and the number of expensive full-scale tests. Two engineering methods of calculation of aerodynamic characteristics of actual hypersonic vehicles are described in this paper. Cognitive approach was used for selecting the method for solution of the posed problem. Thus engineering research method was used to determine the aerodynamic characteristics of the hypersonic vehicles with the additional application of semi-empirical theories. The hypothesis that the momentum flux on a surface element is determined by its local pitch angle relative to the approach flow was used as well.
A detailed description is given for the process of calculation of aerodynamic characteristics of hypersonic vehicles according to the selected engineering method. In particular, the results are presented for the investigation of the layout aerodynamic characteristics of actual hypersonic vehicles: “Clipper” Russian project and “Falcon HTV-2” USA project.
The method does not take into account the interaction of the boundary layer with the non viscous flow. Thus during calculations for low angles of attack it is necessary to use more detailed models, which take into account the boundary layer presence. This method works well for nearly spherical and other blunt bodies and cannot be used for very thin bodies.
The program and its results can be used for the development of advanced hypersonic vehicles and estimation of their characteristics at early design stages. The method gives good results for the drag coefficient of simple body shape; the trend for the lift coefficient is also correct. The proposed method is also suitable for taking into account the influence of Reynolds number in various design modifications and provides for research of various body shapes as well as taking into account the boundary conditions at a molecular level.
Keywords: engineering methods in aerodynamics, characteristics of aerodynamics hypersonic cruise vehicle, Reynolds number , transient aerodynamics |
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Myint Z. M., Khlopkov A. Y.
Investigation of aerothermodynamics in space is a key technology for the design and optimization of space vehicles since it provides the necessary databases for the choice of trajectory, guidance, navigation and control, as well as for thermal protection and propulsion systems. The purpose of this work is to provide a method for calculation of aerothermodynamic characteristics during the flight in rarefied, transitional and continuum regimes, which could be used for rapid engineering calculations at early stages of reentry vehicle design.
Space vehicle design basically depends on databases, which provide the forces, moments, temperatures and heat fluxes along the chosen trajectories. The particle-based Direct Simulation Monte Carlo (DSMC) method may be used for the rarefied flows, and Navier-Stokes equations may be solved by using algorithms from Computational Fluid Dynamics (CFD) for the continuum regime. Thus aerothermodynamic characteristics of the high-speed rarefied gas flow are obtained by using the DSMC method on the basis of three different gas-surface interaction models — Maxwell, Cercignani-Lampis-Lord (CLL) and Lennard-Jones (LJ). The local-bridging method is used in transitional regime.
The paper presents the results of aerothermodynamic characteristics calculations for reentry vehicle with the use of DSMC method. Results show that the values of heat transfer coefficients are sensitive to application of various gas-surface interaction models. Also results of calculation of heat transfer coefficient on sphere in transitional regime by using local-bridging method are described. Comparison of the calculation results for the spherical body in transitional regime with experimental data has shown that the modeling results are correct and the calculation error is below 5%.
The DSMC method was used during the analysis of aerothermodynamic characteristics of reentry vehicle in free molecular flow to circumvent the complexity of solving the whole Boltzmann integro-differential equation. As the flow changes from rarefied to continuum regime, the DSMC method requires many more simulated molecules, larger computer memory and longer CPU runtimes. Thus local-bridging method is used to rapidly obtain aerothermodynamic characteristics for this transitional regime.
The paper shows that it is possible to study the aerothermodynamic characteristics of the space vehicle at altitudes from 120 to 60 km by the use of local bridging method. Presented methods and results may be useful for the design of the thermal protection systems of modern and advanced reentry vehicles and construction of their de-orbiting trajectories.
Keywords: aerothermodynamic characteristics, high-altitude aerodynamics, heat flux in transitional flow, local bridging method |
Aviation technologies |
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Nikolsky A. A.
Purpose – The purpose of this paper is to describe a new general approach for airfoil shapes parameterization. Applications to airfoil optimization are also discussed.
Design/methodology/approach – The concept of a base airfoil spline which allows approximating a contour of an airfoil with necessary and sufficient geometrical accuracy is entered. The concept of an aerodynamic airfoil spline which allows approximating a contour of an airfoil with accuracy sufficient for problems of aerodynamic design is entered.
Findings – The results of numerical solving an inverse problem for helicopter and transonic airfoils demonstrate the effectiveness of the established method for optimization of airfoil performance. The results are verified by RANS calculations. All possibilities of technique will be seen in further researches.
Originality/value – The paper provides a new general airfoil geometry description. The advantage of this technique over the other parameterization methods is its generality and simplicity. Just ten design variables are enough to describe an arbitrary airfoil in optimization processes considered.
Keywords: airfoil, spline, optimization, designing |
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Nedelin V. G., Parafes S. G.
One of the most important problems of the maneuverable unmanned aircraft designing is a security from a flutter and aeroelastic stability with the help of automatic control system (ACS). The aeroelastic interaction between unmanned aircraft and ACS can be presented in the form of a multiply-connected loop. There are two line feedbacks in this loop: through the malleability of the actuator and the control loop. This structure indicates that in addition to the flutter the stability losses in the system «actuator– rudder» and in the loop «elastic aircraft– ACS» are possible. The problems associated with stability of the multiply-connected loop «elastic aircraft– ACS» should be considered at the stage of preliminary design. Detection of the oscillations presence fact in the multiply-connected loop only in the design final stages (the laboratory and the flight tests) leads in significant additional to great money costs and time consuming to eliminate undertaken measures. In this paper the iterative approach for solution to the problem of ensuring of maneuverable unmanned aircraft aeroelastic stability at the stage of preliminary design is considered. The approach includes three stages. The first stage is the choice of the structure and main parameters of aircraft circuit stabilization from the view pointof its regarded aeroelastic characteristics. The second stage is subsystems rational individual design: the air frame and the ACS (including stabilization system and actuator). The third stage – the harmonization of the structure and parameters of the airframe and ACS with the purpose of safety requirements satisfaction for the flutter and aeroelastic stability with the help of ACS.
- There are developed with the purpose of proposed approach implementation
— mathematical models of stability of the system “actuator – rudder” and the loop “elastic aircraft – ACS”;
- coordination methods for parameters of constructive-technological solution to the airframe and ACS (the actuator and stabilization systems) with the viewpoint of requirements compliance of the aircraft aeroelastic stability.
- An example of solution to the problem of airframeand ACS parameters coordination with the related requirements to aeroelastic stability is shown. The example illustrates the possible recommendations for ensure of aircraft aeroelastic stability with the help of ACS.
Keywords: unmanned aerial vehicle, design, automatic control system, flutter, aeroelastic stability |
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Yaremenko A. V., Nikitchenko Y. A., Popov S. A.
To investigate the mutual influence of hypersonic vehicle airframe and functioning scramjet engine at various angles of attack.
A special algorithm of calculation of performance in cruising flight mode has been developed to carry out numerical research on the basic engine characteristics and external aerodynamics of the hypersonic vehicle. This algorithm connects main engine performance with external vehicle aerodynamics. Characteristics of the engine and its influence on tail part of the vehicle are calculated for two-dimensional flow model by using “Fluent” Computational Fluid Dynamics (CFD) software. External aerodynamics of the hypersonic vehicle is calculated for three-dimensional flow model by using «Newton» software, which was developed in Moscow Aviation Institute (MAI, Department 105, «Aerodynamics of aircrafts»).
The paper considers the specific features of numerical research of integrated “airframe-scramjet” aircraft configuration. Such configuration is typical for hypersonic vehicles. A special method that combines standard CFD software with in-house created tools was developed to perform the calculations. The calculations have shown that the deviation of the angle of attack of a hypersonic vehicle from its cruising value causes significant divergence of airframe aerodynamic performance from linear variation law and leads to considerable reduction of the scramjet engine thrust.
The developed algorithm and calculation results can be used at early stages of development of the advanced hypersonic vehicles.
The research on creation of hypersonic air vehicles attracts a lot of attention during the recent decades. These vehicles include both manned and unmanned aircraft of different types with various missions as well as guided missiles. Development of hypersonic vehicles with scramjet engines requires special methods, which differ fundamentally from those used for development of aircraft with other types of engines. The developed algorithm takes these differences (in particular, the airframe-engine interactions) into account.
Keywords: hypersonic vehicle, ramjet, aerodynamic characteristics, engine thrust, computational fluid dynamics , CFD, integrated aircraft configuration «airframe-scramjet» |
Space technologies |
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Letova T. А., Yakovishina D. D.
In this article the development task of algorithmic and simulator complex software allowing to form the plan of information transfer from the space vehicles tandem onto the receiving information points is considered.
Analysis is carried out for two variants of the plan transmission informations obtained as a result of fulfillment supporting observation plan: in the first case the information from tandem goes to the receiving information points; in the second case the information from tandem goes directly to the receiving information points as well as through relay satellite onto the receiving information points.
The simulated results can help to choose a data transferring plan when the volume of transmitted information will be maximum (maximized).
The present study provides a starting-point for the further research in the international aerospace industry.
Necessity for the practical solution to such kind of tasks arises because of the radar interferometric survey of earth surface now is in use on the basis of space vehicles tandem, which gives a chance to create the digital models of relief and earth locations with high precision, allows to carry out all-weather monitoring of natural and man-made disasters consequences, makes possible to solve the problems of ensuring defense and safety.
Keywords: spacecraft, zone of radio visibility, relay satellite, motion forecast, plan transferring information, volume of on-board memory, supporting observation plan |
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Karagodin V. V.
Object of the research is the approximate and numerical methods for flight vehicles trajectories calculation, used in ballistics design during cycle development, and estimations of their basic design-ballistic characteristics.
Article theme is comparison of solution methods to the motion differential equations at the extra-atmospheric site of a trajectory in accuracy, main parameters, algorithmic and program methods of speed calculations increasing.
The activity purpose is working out and selection of the most effective methods of motion differential equations solution by "accuracy-speed" criterion, allowing to reduce volume and time of calculations with the decreasing of calculation accuracy level of trajectory kinematics parameters in design-ballistic problems.
The accuracy characteristics of the known and new methods of the motion equations solution are received with the help of numerical calculation computer methods with their corresponding increasing of process and calculation time.
In this article it is shown that for motion problem at the extra-atmospheric active trajectory leg the known approximate numerical methods of the motion equations integration are more effective in accuracy in comparison with others. The analytical solution to linear motion equations is received. Numerical methods which can be used for the approximate of solution to the motion equations with large step of integration are resulted. Algorithmic methods of calculation speed increasing are offered. Semianalytical formulas are developed for derivative calculation of motion parameters according to factors of the pitch program.
Results of activity can find application in the field of ballistics design and selection of the basic design-ballistic parameters of flight vehicles. For the considered problem the most effective parameter "accuracy-speed" is the modified by Nuström’s method with semianalytical expressions for derivative calculation of trajectory kinematic parametres. The use of this method allows to reduce solution time of regional ballistic problem not less than in 2-3 times in comparison with other considered methods.
Keywords: motion equations, the extra-atmospheric trajectory active leg, solution method, accuracy, response |
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Nogov O. A.
The article presents materials about creation of general (long-term) and detailed (daily) plans for conducting of data relay and communication sessions in the Data Relay and Communications Control Center of Multifunctional Space Data Relay System “Luch”.
The planning of information relaying different types is carried out on the basis of applications consumers — Mission control centers of Low Earth Orbit spacecraft (SC), boosters, launch vehicles. Requests are subdivided: on long-term ones – during a weekly period, operational ones – are distributed in less than one day before the planned work beginning, emergency ones – may be issued in less than 3 hours before the planned relay session. Managing Space Objects are taking advantage of up to 3 relay satellites.
The aim of this work is to offer a satisfaction methodology of multiple received varying degrees of urgent requests with given limitations of applications by ground relay stations (GRC) and airborne relay systems, exceptions enabled the same ground relay stations by various spacecraft-subscribers with overlapping range of communications sessions opportunities. Hence it is needed to address the optimization of planning relay sessions.
As the objective planning mission function is taken by the functional, so we need to take into account the implementation of the planned relay sessions with the resource use of ground relay stations. The criterion of plan optimality is to ensure the maximum number of declared sessions presented to the alignment of all remaining resources used by GRC.
To solve the problem of optimal planning relay and communications sessions is used a so-called greedy algorithm. For this task, the principle of optimality can be formulated as follows: for the first step we obtain the certain (running) solution to the spacecraft (SCm) using a “greedy” algorithm. Then, the best solution to sessions distribution for the next spacecraft (SCm+1) is the set of “close” and current solutions. The resulting solution will be a new current solution. This process is repeated until you have examined distribution of sessions for all declared spacecraft.
The resulting method allows for anyone to quickly obtain a practical solution, which is close to the optimum.
So, one of the basic problem was scrutinized by the Data Relay and Communications Control Center of the sessions planning.
The methodology and the obtained results are interesting for researchers in the field of space technology, as well as for graduate and undergraduate students.
Keywords: data relay, communication, planning |
Aerospace propulsion engineering |
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Vazhenin N. A.
As recent studies of thin time structure of electromagnetic emission of stationary plasma thruster (SPT) have shown, such stochastic process, in addition to a purely thermal component, contains a non-thermal component representing stochastic seguence of radio pulses with complicated internal structure.
The purpose of the paper is compare results on electromagnetic emission of stationary plasma thruster obtained by mathematical models and by test.
Mathematical models, suitable for the phenomenological description of self electromagnetic emission of stationary plasma thruster are analysed on the basis of results of test studies for such emission statistical characteristics. The comparative analysis is made for statistical characteristics of signals obtained by test and characteristics of phenomenological models of such signals.
Depending on the SPT operating mode and the frequency range used the models Middlton, Hall, Merts, Vejbull, Laplas or Hilbert frequency range for the description of statistical characteristics of radiation SPT models of Middlton's, may be used of SPT emission. The obtained results allow reasonable approach to the development of mathematical models for the emission of specific types stationary plasma thrusters.
The study presented provides a starting-point for further development of simulation models for stationary plasma thruster emission.
The results obtained can be used to analyze the effects of stationary plasma thruster electromagnetic emission radiation on the operation of satellites radio systems.
Keywords: space communication, pulse noise, stationary plasma thrusters, mathematical models |
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Bogomolova T. V., Melnikov O. V.
The results of the calculations of the static strength of long blades of steam turbines with the software package ANSYS-WORKBENCH are presented. Described and illustrated the basic steps of calculations. The results are compared with data of known methods.
Long blades of last stages of steam turbine.
The method of strength calculation in software package ANSYS-WORKBENCH is based on finite element theory. For solid model finite element grid was constructed. The tensile stress was calculated by applying of rotation (3000 rpm). And the bending stress is result of applying computational fluid dynamic software package ANSYS-FLUENT. Boundary conditions for this case are total pressure on inlet and static pressure on outlet. The turbulence model is k-ε Realizable.
The strength of blades was calculated. Comparison between calculated stresses and data of known methods was done. All results in a good agreement. The maximum stress for 1760 mm blade is 361 MPa.
Keywords: strength of blades, static loads, tensile stresses, bending stresses, breaking point |
Material authority |
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Odnokurtsev K. A., Vlasevsky A. A., Lukin P. A.
Movements of manipulator drives when performing coordinate positioning of an object in space.
Movements calculating methods for manipulator drives when performing the object coordinate positioning, based on the initial and final coordinates of three of its points.
Positioning manipulators drives movements’ calculation when performing the installation of assembling equipment and assembling works in aircraft manufacturing in order to reduce laboriousness of the positioning process performing.
Matrix transformations and trigonometric functions calculations.
Initial coordinates of tree object’s points are obtained by measuring on the object with any coordinate measuring machine (CMM). Final coordinates of tree object’s points are obtained by measuring on geometrical model of the object. Some methods of calculating for two special cases of coordinate positioning are offered. The first one is for 6-dimensional manipulator with three linear and three rotational drives and the second one is for a complex consisting of three 3-dimensional linear manipulators. Also, application software to performing both calculating methods has been developed. The offered methods of calculating provide the possibility of object’s positioning with non-iterative movements.
Performing of assembling equipment installation and assembling works in aircraft manufacturing.
Keywords: positioning, manipulator, coordinates, movements’ calculation, automation |
Control and navigation systems |
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Afonin A. A., Kurmakov D. V., Yamashev G. G., Sulakov A. S.
This article deals with questions of small-sized microcontroller computer module design for modern systems and complexes of orientation and navigation, gravimetry and guidance of air-sea dynamic moving crafts. The main goal is development of printed circuit board of the computer module on the base of up-to-date microcontrollers for collecting and processing data as a component of a strapdown gravitation-inertial navigation complex (SGINC).
When creating the computer module on the base of up-to-date microcontrollers we used computer aided design and modern methods of collecting and processing data in integrated navigation systems construction. On the base of required performance analysis of the SGINC computer module in the whole and technical characteristics of up-to-date microelectronics chips we have chosen a rational variant of the computer module hardware. The main criterion herewith was the processing power of microelectronics chips that could support the SGINC performance.
A general concept of the computer module creation for strapdown gravitational-inertial navigation complex (SGNС) was presented along with computer module schematic diagram. We give a description of the computer module software features, we map out a further work vector aimed at the computer module improvement both in the direction of enhancement of its functional capabilities and optimization of the process of the device development for the purpose of ensuring its compliance with the requirements of international aircraft standards. We present the results of work on the computer module prototype creation.
The SGINС presented has no analogs in the world navigation and can be used for correlated extremal navigation and for gravimeter surveying on board of unmanned aerial vehicles. Design of SGINC computer module allows for creation of completed semi-natural model of SGINC and carrying out testing of the integrated complex.
Keywords: microcontroller, computer module, printed circuit board, topology, software, real time operating system, gravimetry, orientation, navigation, strapdown graviinertial navigation complex |
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Kurshin A. V.
The problem of location determining of an artificial Earth satellite (AES) using the Global Navigation Satellite Systems (GNSS) GPS and GLONASS was considered. To improve the accuracy of navigation it is proposed to use a modified navigation algorithm, which, in addition to measurements of GNSS, uses information about the motion of the satellite model in non-central gravitational field of the Earth. There is also considered the specific challenges with which the companies pursuing international manufacturing strategies are faced.The mathematical modeling of the orbital segment GNSS GPS and GLONASS, disturbances, and movement of space consumer were used for the research. The disturbances on the satellite, inaccurate knowledge of satellite ephemeris and time were mathematically modeled.The resulting navigation algorithm can be used for navigation of nano-satellites, remote sensing satellites and scientific satellites. In addition, these algorithms can be used in navigation of aircraft moving along the ballistic trajectory.The present study provides a starting-point for further research on advanced model of orbital consumers. Research can be carried out by the refined model of the consumer motion. The correct motion model is able to compensate the perturbations provided by non-spherical gravitational field of the Earth, gravity of the moon and the sun, the pressure force of sunlight.The use of modified navigation algorithm can significantly improve the accuracy of consumer navigation space, especially in the field of continuous navigation. The appliance of this method allowed to increase the accuracy by 75% in comparison with the least square method. Keywords: satellite navigation, artificial satellite, space consumer, modified Kalman filter, satellite motion model |
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Afonin A. A., Sulakov A. S., Yamashev G. G., Mikhailin D. A., Mirzoyan L. A., Kurmakov D. V.
This paper presents a new approach to creation of integrated informative-measuring complex for unmanned aerial vehicle (UAV) automated guidance. The authors consider a variant of the integrated complex including flight planning system, automatic UAV guidance system, and strapdown gravitation-inertial navigation complex — the main source of attitude, navigation, and gravimetric information both for operation of UAV guidance system, and for realization of the flight objective function — execution of automatized vector gravimetric survey. Operation of the main modules of the integrated complex is illustrated with functional and structural diagrams, mathematical models, and operation algorithms. The new approach offered can provide qualitative and quantitative benefits when carrying out aerial gravimetric surveying both at the part of mobile gravimetric measurements, and at the part of planning, information provision, and UAV guidance optimization.
The authors consider the complex, which consists of flight planning system, UAV automatic control system and strapdown gravitation-inertial navigation complex, which is the main source of attitude, navigation and gravity information both for the guidance system and for the target function of UAV mission – automated vector aerial gravimetric surveying.
The suggested technology of aerial gravimetric surveying represents a new qualitative technical and economic level of solution using modern achievements in the field of strapdown and satellite navigation technologies, up-to-date means of electronics, computer science and computer engineering on the basis of a small-sized, agile, low-cost UAV.
The new approach to the design of integrated high-precision navigation and gravimetric complex for UAV guidance considered in the paper substantiates actuality and promising availability of proposed solution, expounds principal fundamentals of the new technology concept of strapdown aerial gravimetric survey by small-sized UAV, presents structures, composition, mathematical models and algorithms of the basic components of the complex.
The results of research conducted demonstrate that creation of the integrated complex will provide an effective solution for orientation, navigation, and guidance problems of UAV, as well as for vector gravimetric measurements problem in accordance with the new aerial gravitational technology.
Keywords: strapdown graviinertial navigation complex, functional algorithm, gyroscope, accelerometer, satellite navigation system, magnetometer compass system, anomaly, vector gravimetry, flight planning system, automatic control system, neural network system, optimum estimation, control law, autothrottle control |
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Ivanchenko A. J.
The purpose of this study is to develop an adaptive control system radar antenna based on the classic proportional and integral differential (PID) controller with application to modern technology management as a fuzzy control module.
The article describes the research challenge and contains a calculation of the mathematical model of a radar antenna and the synthesis of a PID controller. Furthermore, the use of a fuzzy controller to manage the parameters of a PID controller is proposed.
Fuzzy Control is a method used in control systems, in which the mapping of real input and output parameters is presented by the rules of fuzzy logic. Application of the described method with fuzzy logic will automate the tuning process of a PID controller, thus avoiding the manual setting of parameters.
The process of tuning the controller using the fuzzy logic block starts by finding the initial approximation of the coefficients of the regulator. This is usually done using the Ziegler-Nichols method, based on the natural period of oscillation in a closed system and the loop gain. Furthermore, a criterion function is formulated, which is required to find the optimal settings values for the optimization methods.
The simulation results show that the response of the adaptive fuzzy PID controller is comparatively better than the classical PID controller. These experiments show that the usage of an adaptive fuzzy controller to control the radar antenna will lead to positive results.
An approach to improve the characteristics of the radar antenna control system based on the application of fuzzy control is proposed. A comparison is provided with similar systems which use the classical control methods.
Keywords: control system, control radar antenna, adaptive control setting, PID controller, adaptive tuning PID controller, antenna control radar, adaptive control system |
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Khrustaliov M. M., Rumyantsev D. S., Tsarkov K. A.
Numeric and approximate analytical methods in problems for optimal control of quasilinear stochastic dynamic diffusive systems with information restrictions. Galerkin method in problems for optimization of quasilinear dynamic stochastic systems with information restrictions.
Making an algorithm for solving the optimization problem of quasilinear stochastic dynamic diffusive systems. The purpose of research concludes in synthesis of the simple optimal control. Also it is required to get the result corresponding with the earlier made numeric methods.
It is possible to apply the Galerkin method for solving the tasks with the system of matrix differential equations, received using the known results and earlier made numeric algorithms. Then we can use the resulting solution in the general scheme of optimal control synthesis. Finally, the obtained numeric values of the criteria function can be compared with the known ones.
An algorithm based on Galerkin method for optimal trajectories synthesis in problems of quasilinear stochastic dynamic diffusive systems control has been successfully created. Its application allows to use profitable a computer memory in comparison with the numeric methods. The results obtained in terms of the criteria function values correspond with the previously made numeric algorithms.
The algorithm used for solving the problem of the Earth satellite orbit stabilization, where only some of the state vector components can be accurately measured. This situation may correspond to the partial measuring systems failure. In general, information restrictions conclude in the fact that each control strategy component depends on the apriori given set of accurately measured state vector components and can manifest themselves in the different situations.
Keywords: optimal control, incomplete feedback, Lagrange method, Galerkin method, Ito stochastic differential equation, probability density, Earth satellite |
Electrotechnology. Electromechanics |
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Kirillov V. Y., Tomilin M. M.
Intentional electromagnetic interferences which are generated by special technical devices can cause degradation of performance, disruption of operation modes, total loss of operating capability, and damage of elements, modules, and devices onboard of a space vehicle. Cables, connecting the on-board devices and units, due to their large length and presence in different parts of a space vehicle especially on the outer surface of the space vehicle construction can become the main receivers of intentional electromagnetic interferences. Therefore, it is important to provide the required level of electromagnetic interference immunity of on-board cables. For this purpose one must know values of conducted electromagnetic interferences in the on-board cables and coupled transmission lines of space vehicles whichcan arise because of intentional electromagnetic influence. This problem is considered in this paper.
A theoretical basis for solution of the problem is based on classical electrodynamics and electrical engineering. Theory of functions of complex variable and operational calculus were used also.
The paper present results of evaluation of electromagnetic interferences generated in the on-board cables and coupled transmission lines of space vehicles which can arise because of intentional electromagnetic influences. On the base of these results it can be concluded that under the influence of electromagnetic interferences in the form of directional pulsed electromagnetic field in the on-board cables and coupled transmission lines there could be generated voltages and appropriate currents which can cause damages of the on-board elements and devices of space vehicles.
The paper presents a part of research work devoted to calculation of electromagnetic interferences in the on-board cables of space vehicles.
Keywords: electromagnetic interference, electromagnetic field, on-board cable, coupled transmission line, spacecraft |
Technical cybernetics. Information technology. Computer facilities |
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Zvonareva G. A., Ibragimov F. R.
There are the aspects of control software development of the interface device considered in this work. The interface device is a part of the onboard equipment of the satellite service control channel and this device plays key role in the controlling the satellite from the ground control station. The main functions of the interface device is receiving messages from the ground control station and sending telemetry data to ground station. Additionally the device must receive and handle the control signals from satellite onboard apparatus. The interface device consists of hardware and software. The most important functions are performed by the control software.
The previous versions of the satellite also contained interface device. However from version to version the functions of interface device are becoming more complex and the amount of functions is also increasing. Therefore control software development of the new version of the interface device is an actual issue.
In previous versions of interface device functions were performed consequently according to a predetermined cyclogram. But by increasing complexity and amount of the tasks performing by the interface device there is a need to consider the new approaches in the organization of the computational process including approaches using real-time operation systems. It was decided to develop the control software of the new interface device with using the real-time operating system, which is based on the modular concept and the blackboard style.
The using of this operating system allows to split the whole control software into separate modules. Each module can be developed and used relatively independently of the rest modules. The blackboard concept allows to degree the amount of interactive interfaces between modules of the control software. The modules interact with each other only by using the global database called blackboard. The selected operating system also provides ways of flexible priority assignment and performing mode configuration of the different modules of the control program that allows to free up the CPU time of the interface device microprocessor and to meet the specified time limits. These facilities allow to increase functionality of the interface device or to modify the existing functions of the device in the short term.
There was performed self-contained debugging of the control software to verify correct operation of the separate modules. Testing and debugging software by using simulator of external connections showed the correct functioning of the whole interface device in the near-real conditions.
Keywords: interface device, satellite, control software, real time operating system, «blackboard» style, telemetry, simulator of external connections |
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Belskiy A. B., Choban V. M.
An object of the proposed article is the theoretical basis of thermal imaging sighting system formed by electrooptic systems of the aircraft used for analyses, processing and development of recognition algorithm
The aim of the work was developing of the system concept for problems of the attribute space formation, target recognition with the help of thermal imagery of target environment and detection of angular deviation between the target and sight axis of aircraft electrooptical sighting system.
Mathematical and algorithmic description was used for solution the target recognition problem of forming image generated by aircraft sighting system.
A mathematical model and a thermal image recognition algorithm were developed.
Described in this paper methods and algorithms for target recognition of thermal image in aircraft sighting system make it possible to conclude:
- mathematical model of thermal imaging provides images of phono-target environment for further analysis, processing and research, based on algorithm of image recognition;
- algorithms for analysis and pattern recognition provide:
- perform pre-processing thermal image phono-target environment (image smoothing and underscore boundaries),
- get a segmented image as a separate object with known coordinates of the boundary points of the contour,
- calculate the geometric characteristics of the selected objects,
- perform an assessment azimuth targets, determine the expectation function and mean squared deviation of the geometric characteristics used to classify each object,
- analyze the selected objects and define the target,
- calculate the angular coordinates of the object-target.
Keywords: mathematical model of thermal umaging, image preprocessing, image segmentation, edge enhancement of the image, image recognation |
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Shatovkin R. R., Likhachev V. P., Ryazantsev L. B.
A maneuvering target has the strong influence on the performance of the automatic tracking system. The failure to detect the beginning of its maneuver often leads to the failure of tracking due to the appearance of large errors because of the wrong gauges of the real behavior of target. Modern and future electronic systems of this class have to include special devices to detect and determine the intensity of maneuver – indicators intended to correct the settings and filters support structure in accordance with the real situation.
Information used to make decisions about a maneuvering air target and its intensity can serve as a tool to accelerate the solution convergence using an approach based on target echo signal which is the carrier of special information used to accelerate convergence.
The particular research interest is the building up these filters by means the theory of systems with random jump structure. The characteristic feature of the data processing algorithms in the system with random jump structure is the ability to integrate different models of the aircraft motion and integrate information gauges and indicators.
The main goal of the present work is the developing of the algorithm for automatic tracking of maneuverable aircraft with the usage of the information contained in the echo signals; in the interest of correction filters automatically track structure.
To assess the accuracy characteristics of the algorithm support determined the standard error estimates range this algorithm. To realize this, the simulation space fighter was moving on 30 different linear target trajectories, performing "battle turn". The obtained values of the deviation estimated the range from the true range values of the aircraft were then averaged by the number of tests.
The proposed algorithm based on the theory of systems with random jump structure in conjunction with the additional information from the phase difference maneuver indicator was compared to the algorithms based on Kalman filtering. Research results showed that the developed algorithm provides more stable tracking of the target range, than the algorithm based on the model with fixed parameters.
Keywords: on board radar, optoelectronic system, no signal state, air target, line speed |
Radio engineering. Electronics. Telecommunication systems |
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Anamova R. R.
Subject of research include waveguide transmission lines of the ground-based large-sized phased antennas for the aeronautical communication.A problem of waveguide layout is typical for antenna arrays with great number of emitters because of bounded space of antenna aperture and great number of waveguide elements to place in it andseveral types of waveguide transmission lines using in the antenna arrays.The modern computer-aided design systems don’t solve the waveguide layout problem completely.
Waveguide layout in the antenna arrangements for the aeronautical communication.
The main purpose of the research is the developmentof the software module for layout design of waveguide transmission line from a power divider to antenna emitters. This module will give an opportunity to optimize waveguide layout and to decrease design and engineering time and costs.
A proposed theoretical framework is based on the topological routing algorithm, set theory and graph-theoretic methods. Delone triangulation is used for the routing fielddecomposition.
Methods of connection routing are reviewed. A new methodology of automatic waveguide layout is suggested. Mathematical models of antenna aperture and waveguide transmission line meeting the topological routing methods’ requirementsare developed. A methodof equal length waveguide transmission lines routing is suggested.The present study provides a starting-point for further research in the waveguide layout automation.
It is planning to apply proposed methodology for waveguide layout algorithmization. Suggested method of equal lengthlines routing can have different applications. Automation of waveguide layout is useful especially for the ground-based large-sized antenna arrays.
Keywords: topological routing, waveguide transmission line, phased antenna array, computer-aided design system |
Economics and management |
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Ershov D. M.
The paper proposes a new quantitative model of strategic performance (QMSP) which is considerably extended in comparison with the original model proposed by M. Hell, S. Vidačić, and Z. Garača. Within the scope of original model linear optimization problem was formulated to find the optimal resource allocation and evaluate strategic performance corresponding to this allocation. In this problem the criterion function was the total level of main strategic objectives’ accomplishment while constraints were dictated by the structure of cause-consequence relationships between strategic objectives and limitations on resource amounts. Objectives and activities were suggested to be linked with one-to-one(zero)relationships. For an objective to reach x percent accomplishment level, corresponding activity has to be implemented the same percent.
We propose to extend the original QMSP so as to take into account three additional conditions which seem reasonable for us:
- Implementation of one strategic activity can influence reaching the set of objectives
- Strategic activities are divided into two groups. The first group is formed byproject activities. If an activity is of project type then it have to be implemented completely (all necessary resources must be spent to its implementation) or not be implemented at all. The second group is formed by process activities. If an activity is of process type then it can be implemented partly depending on resource amounts spent to implementation of this activity (all activities in original model are process activities).
- For each objective several alternative activities (groups of activities) can be specified. Optimization process must enable choosing only one activity (group of activities) which should be implemented.
To find optimal resource allocation considering new conditions the optimization problem containing binary and continuous variables is formulated. This problem (initially it isn’t linear) can be transformed to mixed 0-1 linear problem and solved with branch-and-bounds method or with some heuristic (metaheuristic) algorithm.
The new QMSPE was proved to be more suitable for evaluation of aerospace enterprise’s strategic performance. It was applied within strategic planning process of “ESTO-Vacuum”(this company produces vacuum equipment for production of avionics)and demonstrated its high potential as a planning instrument.
Keywords: quantitative model for enterprise’s strategic performance evaluation, problem of optimal resource allocation, , strategic planning, balanced scorecard |
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Kulikova A. N., Golovanov P. V.
The presented paper studies economic relations associated with the management of an aviation enterprise, which uses a budgeting system integrated with a quality management system.
The paper covers the problems of defining key performance indicators and performance criteria for the processes that take place within the framework of the budgeting systems of aviation enterprises.
The paper aims at developing a methodological approach for the creation of budgeting systems of aviation enterprises, which would be integrated with their quality management systems.
The published works of domestic and foreign economists in the field of planning, internal operation cost accounting, budgeting, quality management systems, restructuring and crisis enterprise management served as methodological basis for this research. The distinctive features of the methodological approach are the achievement of the stated objectives and performance criteria values, which were defined within the framework of the budgeting system, and management of deviations within the framework of the mechanisms of the quality management system.
The results of the research can be used for the development of a single integrated system aimed at achieving the set goals and results. This integrated system would incorporate the quality management system and budgeting system. Usage of the developed method allows determining the performance criteria and assigning people, who would be responsible for the achievement of their desired values within the aviation enterprise with the help of the abovementioned system. Usage of this method also allows working effectively while attaining the planned indicator values and improving the system, if the targets are not accomplished.
The research resulted in distinguishing the basic principles of the creation of budgeting system for performance indicator management within the framework of management that is carried out according to the objectives and performance criteria of the quality management system.
Practical application of integration of quality management system with the budgeting enterprise subsystem covers the demand for a management subsystem, which would allow the following: planning, ensuring the resources availability, comparing actual and planned indicator values, as well as implementing necessary measures according to the comparison results.
The problem of quality assessment and management is a very topical issue of today. The paper offers a way to improve the overall quality of aviation enterprise operation via integration of the quality management and budgeting systems.
Keywords: quality management system, budgeting, system of key performance indicators, competitiveness |