Vol 18, No 1 (2017)

The purpose of reducing the prime cost and time of manufacture was always timely. The additive technology can be the alternative to the traditional one which uses tools treatment of materials. The first commercial equipment to make products by additive technology was made more than 30 years ago. Due to the termination of the patent restrictions the rapid development of this technology has been observed recently. The equipment operating by the additive technology is called 3D printers and manufacturing process 3D-printing. The application of additive technology can significantly reduce the use of instrumental treatment or completely abandon it. One of the main advantages of the additive technology is the possibility of manufacturing products of complex geometric shape, it can also include internal cavities. Many types of 3D printers were designed; it varies not only by a pressing method, but using materials. In present time it becomes available to print by metal, ceramic and plastic which can be filled with glass or carbon. The framework of electrical drive-flywheel, which is used at orientation system of satellites, was printed to test the additive technology. The printing was done by FDM and SLS printers. The frameworks have been exposed to unfavorable external factors such as vacuum, elevated temperature and humidity. SLS technology of printing by powder of polyamide was identified as the most promising one.

Creation of a number of new mobile communications technologies has led to the development of a variety of mobile applications, in particular in the field of distance education. It is information and satellite technology, ie distance learning technologies based on the use of space mainly satellite-based data transfer, as well as global and local networks for interaction between the participants of the educational process, student’s access to information and educational resources that is the most innovative and popular. Absence in remote and inaccessible areas, where insufficient or completely absent cellular and wireline telecommunications, will no longer be an obstacle to the implementation of distance learning through a safe and reliable Internet access. Mobile satellite technology makes it possible to use fast data channels and can send and receive e-mail, files, access databases, corporate networks, browse Internet pages, video conferencing. Regardless of geographic location of mobile users of distance learning satellite network will help easily transfer large amounts of data, such as files of the executed works. One of the purposes of mobile satellite communications is to provide communication during outdoor events (training, seminars, presentations, etc.). There is a mechanism of support and development of distance and e-learning in distance learning system (LMS) Moodle - a formal cross-platform mobile 2 Moodle Mobile app, the code of which is publicly available. By order of distance learning technologies SibSАU Center, which uses the Moodle LMS, the terms of reference were drawn up for the modification of Moodle Mobile 2 in order to provide the user with more information about the learning process. As a result of studying the structure of Moodle Mobile mobile applications and further development, the server component was unfinished, by creating a php script. Additional modules are also implemented in Moodle Mobile by using HTML, CSS, JavaScript, Ionic framework, Apache Cordova, which reflect: the contact information of the course teachers; curriculum with the presentation to the user a list of subjects per semester, the teacher’s name and the final unit discipline. Applications for the Android operating system have been assembled. The app has been tested by the service TestFairy, integrated into the system of distance learning SibSАU and posted on the portal of distance learning SibSАU called “Moodle Mobile SibGTU” with the brief instructions for installation. Additionally developed possibilities of this application enhance the level of communication, information and academic performance of students, as well as provide access to information in offline mode (without internet access) provided that before this information has been viewed. Learners can be both students and students of additional education who are trained remotely, that is, employees of various fields, which created courses.

Sandwich panels are widely used constructional parts of modern spacecraft bodies and have various edge-fixing conditions. In designing of such panels there is always a need for an analytical formula to determine with reasonable accuracy the fundamental frequency which is a convenient assessment of sandwich construction efficiency that takes into account the mutual influence of its stiffness and mass. The article observes fundamental frequency determination for rectangular sandwich panel with all edges rigidly clamped. The panel has symmetrical layer package, consists of two identical face-sheets and orthotropic core. The approach uses Galerkin’s method to solve motion equations and the solution of a bending problem of the beam with rigidly clamped edges as a function that approximate panel shape. This reduces the problem of determination of the dimensionless frequency parameter which depends on the panel geometry, inertial and elastic characteristics. The frequency parameter is calculated both including and excluding rotation inertia. In the latter case, an analytical formula for fundamental frequency is the result of this approach. Influence of geometrical, elastic and inertial parameters of the sandwich panel to its fundamental frequency have been analyzed by using the analytical formula. Comparison of calculation data with finite-element package modal solution shows that obtained formula gives high accuracy and low usage of computational resources, which is especially useful in designing process where restrictions are imposed on the first frequency of sandwich panels.

The article deals with the functional and algorithmic implementation of multi-version execution environment of modules as components of the onboard software of autonomous pilotless objects by means of real-time operating system. One of the approaches to implement multi-version execution environment implementation of the principle of a pseudo-parallelism (imitation of concurrent execution of tasks (threads) by dividing the time of their execution) are given. It was determined that the functional capacity of the operating system, expressed in the presence of threads scheduler and time base, as a tool for the implementation of actions through a strictly selected intervals, queuing mechanism, messaging, capable of being used as a functional support of sought environment. The article also announced the possibility of porting, which is adapting to the execution on the single-chip microcomputers (microcontrollers), which, in turn, contributes to capability of testing the idea on available workbench. Messaging process between multiple threads has been implemented by cyclogram, as the procedure of returning of voting result by queuing mechanism, which is a safe way of interaction of threads with each other and solves the problem of sharing multiple threads to the same hardware resources, whose role in this case played by memory. The main API-functions accompanying process of algorithmization of the exchange of messages, such as start scheduler, the creation of threads, creating of the queue, entry in the queue, reading out and others are shown. In the article it is viewed messaging mechanism, in conjunction with the scheduler and priority system implemented by real-time operating system, allow building more flexible algorithms of voting, that can vary the weights of N-versioned modules, and as a result, affect the reliability indices of multi-version software, including for implementation multi-version execution environment of onboard software of autonomous pilotless objects.

Separating of homogeneous production batches of the electronic components used in the electronic units of the space systems is one of the most important problems which must be solved for improving quality of such units, their lifetime and reliability of the space systems. The quality of the electronic units is increased due to both more coordinated work of the EEE components which have identical parameters and increase of quality level and the accuracy of the destructive tests due to a new opportunity of guaranteed selecting electronic elements for these destructive tests from each production batch. In this paper, we solve the problem of precipitations of homogeneous batches of industrial products using Gaussian spherical mixture models and the EM algorithm with agglomerative greedy heuristic procedure. The EM (Expectation Maximization) algorithm is an efficient means of splitting a mix of various distributions. However, in case of multi-dimensional Gaussian distributions in a space of very large dimensionality, this algorithm is actually unworkable. In case of large volume of input data, this algorithm demands too complicated calculation for rebuilding its correlation matrices at each iteration. In case of small data volume, algorithm leads to detection of fake correlation in data. In our paper, the shipped lot of the electronic components for space industry is represented by a data set of non-destructive test results which is considered as a mixture of spherical Gaussian distributions (SGD). It is shown that this algorithm allows to efficiently determine homogeneous products batches which are rather large (thousands units) using of high-dimensional array of data (up to some hundreds dimensions). We show that, using this mathematical model in combination with new algorithms is capable to separate the homogeneous batches of the electronic components efficiently and reach more accuracy and stability of results in comparison with random multiple start of the algorithm.

This article deals with the development of the mathematical model of oil price forming. To develop a proper mathematical model the methodological principles are defined: three axioms that establish specific properties of oil as a commodity including tight oil. Among the factors of oil pricing the major factor was selected, the dominant factor is an imbalance of supply and demand for oil in the world market. The principles of the mathematical model are presented in three theorems. The first one assumes that for any excess of supply over demand, the price of oil tends to zero, i. e., for a sufficiently large number of auctions it is below any given level. The second theorem states that, in the case of the excess of demand over supply price of oil tends to infinity (a finite number of sessions exceeds any given level), in case of the dominance of the imbalance. The third theorem asserts that the most probable forecast implied by the hypothesis that the mathematical model is accurate is a longstanding process of price auto-fluctuations in so called the tight oil range.

Encoding information with error correcting codes provides ability to control the integrity of transmitted messages. In some cases, it also allows correcting errors that appeared during transmission over noise channel. The article provides description of polar codes - binary block linear error correcting codes that achieve capacity for symmetric memoryless channels. Polar codes are based on the channel polarization operation based on idea of polarization transformation of N-bit binary symmetric memoryless channel. The article describes non-systematic and systematic polar encoding operations with bit reversed and non-reversed bit order. It also describes systematic polar encoding method based on two applications of non-systematic encoding of polar codes. The paper introduces polar codes precoding operation which means expansion of information vector of length K into vector of length N corresponding to some polar code C. There is a hardware implementation of precoding operation based on usage of shift registers, which allows precoding any vector of length K corresponding to any (N, K) polar code. The article gives a review and comparison of non-systematic polar encoder architectures with bit reversed and non-reversed bit order. Both architectures are based on pipelined computation principle, partially parallel and have input capacity P multiple of the codeword length N. The paper proposes pipelined architecture of systematic polar encoder for (32, 16) non-reversal polar codes including precoder block and two non-systematic encoders, pipeline diagram is provided. There are two methods of architecture scaling. Scaling in width means increase of capacity of input signal P, scaling in length means increase of number of pipeline stages for each non-systematic encoder. Proposed encoder is simulated using Altera Quartus II 13.0 and ModelSim 10.1. The results of simulation are fully coincide with results of modeling using MATLAB R2016b.

The subject of this research is modern domestic and foreign aviation technology. Technical specifications of civilian and military transport aircrafts, 25 of which made in Russia and 54 abroad, were inspected. The main purpose of investigation is exploration of dependences between aviation technology development and certain major aircraft parameters. Correlation and regression analysis was used for research of dependences as mathematical apparatus. The article contains the results of statistical analysis of relationship between chosen aircraft parameters. The most correlation was found between payload capacity and unloaded plane weight. This was the reason for further analysis and development of dependences. As a result of this analysis all aircrafts were divided by the following parameters: dry weight (less then 75 tons and more than this value) and the place of origin (Russian and foreign). Chow’s test was used to examine the applicability of such grouping. Linear model of dependences gives the same accuracy as nonlinear model so it was used in this research. Dependence of aircraft payload on dry weight was obtained for aircrafts of all groups. Integrated parameters were used for analysis. Confidential intervals for dependence of aircraft payload on dry weight prediction was found. Parameters of only 7 aircrafts were out of 90 % interval. Domestic aircrafts have more payload spread and on the average trail by 2.5 tons of foreign ones. Statistical principles obtained using chosen mathematical apparatus allow analyzing existing design technologies and prognosing the level of development aircraft construction. The similar method of research can be used in various areas of development and manufacturing prospective high tech production, including space-rocket hardware.

The paper investigates the feasibility of the design of space truss structures made of composite materials. The problems arising in the optimal design of multicell composite space truss have been formulated and analyzed. It’s necessary to mount the required equipment on the space trusses, what depends on the number of connecting nodes. On the other hand, a large number of sections and connecting nodes made the structure more heavily and complicate. Thus, the first task is to develop an algorithm for calculating the optimal geometric characteristics of the truss, that is, the number of sections in the longitudinal and in the circumferential direction. Loads on the different elements of the space truss are different. Therefore, it is evident that the different sections of the truss rods must have different characteristics. In the case of composite materials the solutions of further optimization task are necessary. This task is to determine the optimal structural parameters of multilayer beams - such as multilayer structure, the number of layers, reinforcing angles and layer thicknesses. The problem of optimal design of connecting nodes is an important task. The article explores the possibility of connecting nodes, which would be entirely made of composite materials. There are two types of composite connector assemblies, one of which is already known and used in the truss structures of space, and the second proposed by the authors of the article. In order to analyze the strength of the composite connector assemblies and their comparison with the metal assembly finite element modeling of the load nodes was carried out. For this purpose the beam model of total truss was created. This model was used for getting loads in the most loaded node. These loads are used in the more detailed modeling of strength of composite node. The results of simulations suggest promising applications of composite connecting nodes in the space truss.

Rechargeable energy storages are one of the basic components of spacecraft power systems. Characteristics of such energy storages significantly effect on the duration of the spacecraft life cycle in the orbit. In recent years, designers of spacecraft power systems frequently use Li-ion batteries as rechargeable energy storage. This is due to the fact that the inherent energy characteristics of Li-ion batteries are distinctly higher than that of other types of batteries with a similar cycle life. To verify whether a battery satisfies the stated requirements, battery manufacturer performs a series of qualification tests, in particular, the specially designed cyclic tests, which allow estimating the battery cycle life. These tests can take several months (the exact duration depends on the battery model), which negatively affects the overall spacecraft production duration and cost. Performing of the cycle testing according to the principles of Dynamic Stress Test can significantly reduce the overall time of development and production of batteries, which in turn allows reducing the cost of designing and testing of the spacecraft power systems. Dynamic Stress Test is a type of loading testing that allows verifying whether the battery can deliver the specified power to the consumer under all anticipated operating conditions. Basic principles of Dynamic Stress Test are charging and discharging of the battery by currents of large magnitude, and discharging of the battery at constant power, according to special program. Performing of Dynamic Stress Test requires special charge-discharge units that allow performing a full cycle of electrical tests of batteries, including cyclic testing. Providing the required accuracy of measurement and stabilization of certain attributes of Li-ion battery operating modes is one of the problems that arise during the development of such charge-discharge units. The following attributes are of particular interest: charge and discharge currents, discharge powers, battery voltages. The analysis of the charge-discharge unit as a control system allows evaluating the steady-state stabilization error of the required attributes of the developed device. Moreover, using a digital integrator in the control system of the charge-discharge unit allows providing specified values of steady-state stabilization error of required attributes in different test modes.

For launching a spacecraft to the geostationary orbit, it is desirable to start from the area closest to the equator that will allow the launch of vehicle to maximize the speed of rotation of the Earth. To resolve this problem in 1995 in California the Sea Launch Company was registered. For launches of satellites a two-stage rocket “Zenit” was used. Launcher and the technological equipment were mounted on a modified self-propelled oil platform. From 1999 to the conservation of the project “Sea launch” in 2014, with a floating platform in the Equatorial waters of the Pacific ocean 36 launches of spacecraft were made. However, in 2009 Sea Launch ran into financial difficulties and filed for bankruptcy, and the company agreed with the RSC “Energia” on the exit from bankruptcy. And it was reported that RSC Energia sold commercial spaceport to the Russian airline, S7 Airlines. However, both technical and economic problems will remain at the same level. Therefore the possibility of more cost-effective launch of the SPACECRAFT using submarines was studied. Such experience has already taken place. On July 7, 1998 for the first time from a submerged position with missile submarine cruiser of the Northern fleet project “Novomoskovsk” with the waters of the Barents sea with the help of the carrier rocket two micro-satellites were launched into low earth orbit. And on May 26, 2006, also from the waters of the Barents sea from the nuclear submarine “Yekaterinburg” using rocket “Shtil-1” the satellite “Compass-2” was launched into heliosynchronous the orbit. The material shows promising start of the spacecraft from any point of the World Ocean at different orbit using submarines, which is more reliable and efficient than launches from the application project that uses the combination of a launch platform and Assembly-command ship. A comparison of the dimensions of the silos of the submarines, at least, those which have already been carried out launches and mass-overall characteristics of the spacecraft for various purposes, confirms this possibility.

At the moment the Earth’s remote sensing spacecrafts (ERS SC) have found a wide practical application for solving different social and economical objectives, such as getting the information from emergency areas or areas with a low developed ground infrastructure. The major disadvantage of modern ERS SCs is a low efficiency of getting the information from the specified areas of the ground. The existing ways to decrease supervision frequency for a specified ground surface area suppose a vast increase of ERS SC group’s number. However, this way requires large economic costs. The authors have proposed a dual-mode method for monitoring the Earth’s surface. This way foresees to use a mode of global supervision and a mode of regional supervision while in ERC SC operation. The transfer from one mode to another is proposed to be performed by the period change of SC’s circuit of Earth with changing the bigger semi-axis of working orbit using a service propulsion system. In the frames of performed researches a method was created to define the main orbit parameters for global and regional supervisions. To ensure an ERS SC to pass a way through the defined area of the Earth’s surface, we considered phasing when transferring to the mode of regional supervision. As the result, it was developed a definition method of time and financial costs for the supervision mode changing. As it was required to describe mathematically the interconnection of working point, referring to the phasing orbit, with the geographical coordinates of the defined ground area, the authors have developed the method to calculate the ERS SC ways, operating with the application of the dual-mode method for monitoring. The mentioned above methods are the integral parts of the mathematic model, describing the dual-mode method for monitoring, which will become a basis for forming the requirements to the future engines and power plants of spacecrafts. The comparing of the two-mode supervision way with other known ways of increasing the efficiency of getting information from defined regions shows that the application of the dual-mode method allows to decrease essentially the period of survey frequencies with relatively low economic costs and acceptable power consumption.

The optical cluster of a satellite laser range is used for the next goals: to expand laser beams, registering the laser impulses reflected from the satellite and visual observing of the satellite. The perspective decision for these purposes is a combined optical scheme. The purpose of the research was to calculate the optical cluster of the satellite laser ranger. The expander of the laser beam works at the same time for a wide range of wavelengths without any additional refocusing. A laser beam expander is a catadioptric system with the entrance pupil diameter about 42 mm and approximately 300 mm outlet. The optical system of the expander of laser beam for the satellite laser ranging station in the optical and near infrared wavelengths is presented. The collimation of the laser beam takes place in the expander without any additional refocusing for wavelengths from 435 to 2098 nm with a sevenfold increase. The beam divergences for monochromatic radiation are defined as well. In the reverse ray path the expander can be the feeding optics of object tracking lens in the optical range. To avoid vignetting when using the expander as feeding optics of CCD-camera for the satellite tracking (in the reverse ray path), the light lens diameters are calculated. The authors presented two options of a lens of camera: lens containing usual optical glass and lens containing optical glass with special dispersion path: special crown (OK4) and special flint (OF1). Equivalent focal length of a lens is ~ 1760 mm. In the article the analysis of the RMS spot diameter and radial energy distribution of spot has been shown. In the presented optical system Coudě focus is used which allows using the equipment installed permanently. When calculating the optical system, the radii of curvature of all spherical surfaces are recommended by All Union State Standard 1807-75 which reduces the cost of manufacturing technology. The expander of laser beam may be used for satellite laser ranging station and laser radars on the Earth surface.

Ni-Ti alloy has been intensively studied over the past decades. The unique properties of the alloy have allowed using it as a structural material for the creation of instruments and devices in various fields of science and technology, including mechanical engineering, aerospace, instrumentation. Measuring magnetic hysteresis loop is shown that after the deformation of the alloy having ferromagnetic properties. According to the equilibrium phase diagram, the alloys of Ni-Ti at a Ti content above 10 at. % is non-ferromagnetic. Due to lowering of the crystal phase symmetry with a cubic lattice the magnetization appears. In this work we have investigated the magnetic properties and the structure of deformed Ni51Ti49 samples by electron microscopy and X-ray diffraction methods. In Ni51Ti49 samples after plastic deformation the lenticular crystals containing bending contours with a high concentration of internal stresses were found. Bending contours indicate a large distortion of the crystal lattice. The curvature of the crystal lattice occurs due to the large displacements of the atoms. As a result, it can be formed and icosahedral cluster with the structure of the Frank-Kasper. An icosahedron is a twelve vertex polyhedron, which is denoted by FK-12. Furthermore, the crystal can be formed in other Frank-Kasper structures, e. g., FK-16. FK-16 is a sixteen vertex polyhedron with atom located in the center of the cluster. Indexing paintings electron diffraction and X-ray showed that the alloy phase of the Ni-Ti coexist with the structure Ti2Ni and Ni4Ti3. For explaining the possibility of the appearance of magnetization in Ni-Ti alloy samples spin-polarized electron density of states and magnetic moments Ni10Ti6 clusters (FK-16), Ni7Ti5 (FK-12) alloy Ni51Ti49 for electrons with different spin projections: “up” and “down” was calculated. The calculation by the scattered waves (RF) was performed. The results of calculation can be seen that the total electron density of nickel tends to zero faster than the density of titanium. Also shows that nickel becomes negative spin density in the area of r = 3.25-6.7 a. u. and titanium for r > 4.5 a. u. This may result depending on the value of the interatomic distances and to the effects ferromagnetism and antiferromagnetic in order to establish a magnetic clusters. The spectra show a high density of states near the Fermi level that is a characteristic feature of metals, besides there is an increase in the magnetization of the alloy during deformation. The calculations showed that the investigated clusters, not susceptible to deformation, also have a magnetic moment (the average magnetic moment per atom cluster FK-12, is about 1,0 μB, and for the FK-16 is about 0.3 μB. Overall, however, the average magnetic moment is zero, due to the absence of a preferred direction (the chaotic distribution of clusters) for the alloy. However, if the cluster is subjected to tension, the compensation of the magnetic moments of clusters occurs in the alloy, since there is allocated for all atoms direction due to deformation. At the same time, the average magnetic moments of the atoms in the cluster for the Deformed increase to 1.6 μB and 0.8 μB respectively for the FK-12 and FK-16.

This article presents the results of experimental studies of electrochemical dimensional machining model sample in the form of thin-walled hemispherical shell. The studies were carried out using a specially designed and manufactured laboratory installation for local electrochemical machining of details using rotating electrode-instrument. The article presents the main units of used installation for research and the methods of used experiments are decrypted. In this case varying factors during carrying out a series of experiments were composition of electrolyte, electrolyte temperature and also current density. The studies were conducted using as electrolyte an aqueous solution of sodium hydroxide, and also an aqueous solution of ammonium nitrate. When used as an electrolyte 15 % water solution of sodium hydroxide at a rotation speed of the electrode-instrument 20 rpm, at a current density 2-5 A/cm2, temperature of electrolyte 30-40 °С it has been found alignment of the sample surface through the thickness in the radial axes, moreover, the thickness extreme deviations are negligible. Using 15 % of aqueous solution of ammonium nitrate as a main component and 2.5 % of ammonium citrate as a complexing agent does not allow to achieve the desired results. During the analysis of the results extreme deviations in thickness in the radial direction amounted from ±0.05 to ±0.09 mm when removing 0.1 mm of metal. Non-uniformity of metal removal was detected in the axial direction. Thus, it is established, that for carrying out electrochemical machining process of thin-walled oversized details of responsible appointment, which are applied in the aerospace industry, an aqueous solution of sodium hydroxide is most expedient to use as an electrolyte. The main feature of the proposed process is its controllability, efficiency and reducing the environmental impact on the ecological conditions due to lower temperature of used electrolyte and lower concentration of electrolyte.

The article is devoted to the assessment of modern state of enterprises of the military-industrial complex and the analysis of trends and prospects of development. Assessment of the current state was conducted by examining legislative enactments, orders, long-term development strategies of the economy and other documents allowing assessing the quantitative structure of defense industry companies and reflecting their real position. The definition of tendencies of development of the military-industrial complex is made by analyzing the messages of the President to the Federal Assembly for 2010-2015. Almost in each of these messages, one way or another, the President touches on the theme of military-industrial enterprises, reveals further plans for their development, or, after the annual address, there is a list of the orders of the President of the Russian Federation directly related to the defense industry. In the last 5 years the topic of military-industrial enterprises and their development trends are very well represented in the President’s Message, in this regard, this article conducted their analysis and highlighted the key points highlighted in the Letters from 2010 to 2015. The analysis allowed identifying the main directions of further development of defense industry, namely: modernization of production; innovative development; scientific and technological development; the implementation of the rearmament program to 2020; capacity utilization; development of the production of civilian goods; the work on the program of import substitution. The main perspective of the defense enterprises is an innovative development which includes the above trends, and scientific and technological development in this case represents a certain layer, the execution of these prospects. Based on the foregoing, the logical structure of the main trends in the development of enterprises, for each of the schemes justification was created. The typology of enterprises, including such groups as: the research enterprise; the enterprise brand of science; the other (the rest) of the enterprise was proposed. This typology not only helped to divide enterprises according to the nature of the activities, but also on the prospects of innovative development.