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The article is devoted to the application of a group of robotic complexes for military purposes. The current state of control systems of single robotic complexes does not allow solving all the tasks assigned to the robot. The analysis of methods of controlling a group of robots in combat conditions is carried out. The necessity of using a multi-level control system for an intelligent combat robot is justified. A multi-level control system for an intelligent robot is proposed. Such a system assumes the possibility of controlling the robot in one of four modes: remote, supervisory, autonomous and group. Moreover, each robot, depending on the external conditions and its condition, can be in any control mode. The application of the technique is shown by the example of the movement of a group of robots with an interval along the front. The problem of the movement of slave robots behind the leader is considered. When forming the robot control algorithm, the method of finite automata was used. The algorithm controls the movement of the RTK in various operating modes: group control mode and autonomous movement mode. In the group control mode, the task is implemented: movement for the leader. For the state of "Movement in formation", an algorithm for forming the trajectory of the movement of guided robots was implemented. An algorithm for approximating the Bezier curve was used. It allows you to build a trajectory for the slave robot. On the basis of the obtained trajectory, the angular and linear velocity were calculated. In the autonomous control mode, two tasks are solved: moving to a given point and avoiding obstacles. Vector Field Histogram was used as an algorithm for detouring an obstacle, which determines the direction of movement without obstacles. The state of "Movement to a given point" is based on Pure Pursuit as a simple and reliable algorithm for solving such problems. A computer model of the movement of a group of robots was developed. The model is implemented in the MATLAB program using the Simulink and Mobile Robotics Simulation Toolbox libraries. Several different variants of the movement of the RTK group are modeled, which differ from each other in the initial location of the robots and the position of obstacles. The conducted computer simulation showed the efficiency and effectiveness of the proposed method of RTC control.

Purpose: The article covers issues related to providing personal protection equipment (PPE) for medical staff exposed to coronavirus (or similar infection) in the face of global pandemic and insufficient supply of infectious hospitals with disposable overalls As many polymeric materials used to make such overalls do not feature required thermal stability and consequently they cannot be treated with heat disinfection, radiation treatment of protective overalls with electron accelerators for the purpose of their reuse was considered Due to rich experience in addressing the issues of providing high-efficient, physiologically acceptable PPE for the personnel of radiation and chemical hazardous facilities, in particular during Chernobyl nuclear disaster elimination, the Laboratory of PPE for the Personnel of Hazardous Production Facilities, Burnasyan Federal Medical Biophysical Center, could extend methods of assessment and techniques of human protection against high-toxic substances to establishment of protection against microbiological threats Results: The article provides results of analysis and tests of materials for overalls and respiratory PPE currently in use Based on the material tests for radiation stability, air permeability, liquid penetration and protective properties with respect to aerosols, recommendations for improvement of efficiency and comfort of the PPE suite have been developed Conclusion: The study showed feasibility of reusing overalls after radiation treatment However, such treatment is appropriate only in periods of major emergencies during peacetime and wartime, when there are no production capabilities for manufacturing of new products Location of the irradiation facility in the vicinity of consumers (e g medical institutions) is a prerequisite for this treatment It should be emphasized that radiation treatment must be performed under strict supervision of accredited test facilities Further research is required for development and enhancement of PPE and system of its application This will allow to make longtime wear of PPE more comfortable without sacrificing its protective efficiency and develop a manual on product-specific radiation treatment © 2020 State Research Center, Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency All rights reserved

This paper presents an automated method for fault diagnostics in the mechatronic modules of the optical-location stations. Apart from the existing methods, the use of an object native control system for the diagnostics purpose is discussed. It allows us not to use an external hardware during the diagnosis process, because all the information concerning the state of a mechanical structure could be acquired from the control loop information (data from the feedback sensors, outputs of the equalized filters, etc.). This data is enough to detect even the smallest mechanical defects. In future automatization of the control loop data analysis will allow even a low-qualified staff to diagnose and eliminate complex failures, critical for the precise mechatronic modules during the serial production. This is extremely important, because even small mechanical defects can influence the tracking precision of a complete system. This method was successfully implemented for the serially produced modules for the optical-location stations. Realization of the described method requires construction of an adequate mathematical model of a mechatronic module. The authors describe development of an ideal system model, including a servo-drive, a control system and additional hardware, such as sensors and servo-controller parameters. A list of typical failures for these types of systems is presented. This list was obtained after experimental diagnostics of over 100 produced units. The authors also describe how these failures can be presented in a mathematical model. An experiment is required to prove the effectiveness of this method by comparison of the model data with the data acquired.

The task of control for group of special robots for use in high-risk environments (for example, for extinguishing fires, searching for dangerous substances, or eliminating the consequences of accidents) has been solved. Under the terms of the task, robots operate in an industrial-urban environment, that is, the movement of robots is flat. There were analyzed various strategies of group interaction between robots and literature reviewed. Based on the specifics of the task, a decentralized control strategy was chosen. To solve this problem, an algorithm was proposed for the movement of a group of mobile robots with a subsequent visual check of the operation of the obtained algorithm. The developed algorithm includes the following components: constructing the working environment graph of the robot; determining the shortest distances between the base point of each robot and each target point; distributing targets between robots; checking the absence or preventing collisions between robots; building a global trajectory. The implementation of the algorithm works in the MATLAB environment. Group models are developed in the Simscape Multibody package, which allows you to perform physical modeling of both each robot and the group. To make realistic contact between the surface and the wheels of a mobile robot, the use of the Contact Forces Library add-on is required, which considers all the friction and slip forces. This software package can be used to pre-test the work of a group of robots in the context of the task. As a result of the test, the program and model successfully solve the problem, but the simulation time is high due to the large computational complexity of the model and the novelty of the Contact Forces Library package, which will be updated in future versions of the package.

The article reviews such problems as global trajectory forming upon the plane surface for mobile robotic complex, obstacle detection and local detour trajectory building using MatLab standard built-in libraries. The algorithm was divided into several logical parts: fuzzy rule set construction based on prior knowledge about initial vehicle orientation and target position for the global routing; avoiding critical hindrance, which do not allow to continue planned movement; fuzzy knowledge base forming for the local detour trajectory building; ensuring a stable return to the original global

The article presents procedures for modeling the dynamics of the tracked mobile robot. The dynamic simulation of the mechanical part, including the vehicle hull, the wheel system, track assemblies and the virtual track, and the calculation of the interaction with the supporting surface, are performed in the RecurDyn software package using the High Mobility Tracked Vehicle Toolkit (HMTV). The mechanical part is described here as a system of solids, joints and force elements. The software package allows you to specify the type of interaction of tracks with the supporting surface: a caterpillar - a solid body (for example, movement on asphalt), a caterpillar - soft soil (loams, sandstones, etc.). The Becker’s theory is used to calculate the parameters of the interaction of tracks with the ground. Almost all the necessary quantities are available for analysis: coordinates, velocities, accelerations, reaction forces in the hinges, forces in the springs, contact interaction of the track, track tension, etc. The control system cannot be created by means of RecurDyn, therefore the model of such a system was built in Matlab / Simulink. The control system is an artificial neural network, which aim is to maintain a specified longitudinal motion velocity. Using co-simulation toolkit CoLink, the model of the mechanical part is exported from RecurDyn and included in Simulink for the subsequent simulation. The simulation results verified the effectiveness of the co-simulation model, and the method is of great benefit to study motion tracked mobile robot control algorithm in the next step.The article presents procedures for modeling the dynamics of the tracked mobile robot. The dynamic simulation of the mechanical part, including the vehicle hull, the wheel system, track assemblies and the virtual track, and the calculation of the interaction with the supporting surface, are performed in the RecurDyn software package using the High Mobility Tracked Vehicle Toolkit (HMTV). The mechanical part is described here as a system of solids, joints and force elements. The software package allows you to specify the type of interaction of tracks with the supporting surface: a caterpillar - a solid body (for example, movement on asphalt), a caterpillar - soft soil (loams, sandstones, etc.). The Becker’s theory is used to calculate the parameters of the interaction of tracks with the ground. Almost all the necessary quantities are available for analysis: coordinates, velocities, accelerations, reaction forces in the hinges, forces in the springs, contact interaction of the track, track tension, etc. The...

A mathematical model of a single mobile robot is developed. One of the possible situational tasks is considered. The paper deals with the problem of reconnaissance in the premises and the detection of explosive objects. This task is divided into three subtasks: exploration, detection of explosive object and its classification, neutralization. An algorithm for solving this problem is developed. The computer model of the multi-agent system consisting of two robots is designed, proposed algorithm is simulated. Modern tools such as MATLAB, as well as additional libraries such as Robotics Simulation Toolbox, Robotics System Toolbox were used in the simulation. It is necessary to use intelligent robotic systems for the successful solution of special tasks of robotics. To successfully perform real-world tasks, it is necessary to use groups of robots, and each robot can have its own set of sensors and target equipment. The paper describes the composition of a group of heterogeneous robots, the sensor composition and the necessary target equipment to perform one of the typical tasks. Based on the literature review, the structure of the control system of a group of heterogeneous robots was chosen, a hierarchical centralized control system was proposed, as the most suitable for the successful implementation of the task, taking into account the practical implementation. The interaction of the control point with a group of robots is described.A mathematical model of a single mobile robot is developed. One of the possible situational tasks is considered. The paper deals with the problem of reconnaissance in the premises and the detection of explosive objects. This task is divided into three subtasks: exploration, detection of explosive object and its classification, neutralization. An algorithm for solving this problem is developed. The computer model of the multi-agent system consisting of two robots is designed, proposed algorithm is simulated. Modern tools such as MATLAB, as well as additional libraries such as Robotics Simulation Toolbox, Robotics System Toolbox were used in the simulation. It is necessary to use intelligent robotic systems for the successful solution of special tasks of robotics. To successfully perform real-world tasks, it is necessary to use groups of robots, and each robot can have its own set of sensors and target equipment. The paper describes the composition of a group of heterogeneous robots, the sensor composition ...

The microstructure and orientation of TiSi2films produced by pulsed illumination of Ti layers on (111) Si with incoherent light and by vacuum evaporation of Ti onto heated (111) Si substrates were studied by transmission electron microscopy. Both theC49- and C54-TiSi2grains were found to have a number of orientations satisfying the basic crystallographic rules: a high density of coinciding sites at the interface and continuity of high-density planes across the interface. The TiSi2 /Si interfaces studied were shown to be incoherent. The major structural defects in TiSi2layers were identified.

An experiment to study cosmic ray protons and nuclei in the 10 11 –10 14 eV energy range is discussed. The instrument measures the number of particles in a shower, generated by the primary particle in a lead absorber (∼14 cm thick). The instrument consists of two Cherenkov charge detectors, and two plastic scintillators viewed by 4 photo multipliers under a lead absorber (see Fig.1). The geometry factor of the instrument with account for the probability of particle recording is 0.015 m 2 sr. Computer simulations of the instrument operation were made to make sure that the instrument is capable of measuring irregularities in the proton spectrum, which presumably exist at E∼10 12 eV.

Different flame propagation regimes, including a two-wave regime, are studied in a closed pipe with single ignition of GeH4−O2 mixtures. It is shown that, depending on the initial conditions and, in particular, on the composition of the initial mixtures, spatially separated chemical reaction waves for oxidation and decomposition of monogermane are observed in certain parts of the reaction vessel which lead to the formation of a two-layer deposit of GeO/Ge. The temporal sequence of the separated combustion wave and wave from which layers of solid products are deposited, as well as the location of the deposition zones in the reaction vessel, are determined by two interacting chain processes—the oxidation and decomposition of monogermane. The thermal relaxation kinetics of the reactive mixture after passage of the combustion waves is determined by the rate of conductive heat transfer from heated solid particles (reaction products) to the gaseous phase.

The article contains detailed analysis of current scientific approaches and practical achievements in organizing personal protection of the personnel working in conditions of external radiation exposure and air and surface contamination with radioactive substances. The ways of improvement of personal protection equipment are described. The incorrectness of attempts to create PPE from gamma radiation with the energy of over 0,1 MeV--which are currently quite common--is shown. Today the challenge of creating light PPE from beta radiation and soft photon radiation becomes more urgent due to decreasing the annual equivalent dose of occupational exposure of the crystalline lens from 150 to 20 mSv proposed by IAEA. This requires creation of light and usable protective visors (goggles) from beta radiation and photon radiation with the energy of up to 0,06 MeV.

Crystals containing up to 30 wt. % CS2, according to the data of IR and X-ray photoelectron spectroscopy, were isolated from the C60-TSeT-CS2 (TSeT is tetraselenotetracene) system. The unusually high concentration of carbon disulfide results in the complete sublimation of the crystals at a relatively high temperature (520 °C). The electron energy loss spectra of the crystals obtained were measured and analyzed.

We have investigated the possibility of realizing the self-propagating combustion regime for a gaseous mixture of SiH4−NH3−O2 and SiH4-2 with an oxygen content of 0–2%. Calculation of the equilibrium composition indicates the possibility that the target products Si and Si3N4 are formed. We have established experimentally that propagation of the chemical reaction front in the self-sustaining regime with formation of the above-indicated products occurs only in the presence of oxygen. We show that chemical induction, leading to consumption of up to 60% of the initial monosilane, is a chain reaction.

It was shown by the methods of induced electron emission that a transfer of the electron density from C60 molecules to the eight-membered ring of sulfur is characteristic of C60·2S8. The value of the (σ+π)-plasmon energy for C60·2S8 is approximately 1 eV less than that for pure C60. In a high vacuum, the C60·28 surface is depleted in sulfur.

The gas-phase products of thermal decomposition of the C60D19 deuterium fullerite are studied by mass spectrometry. It is found that, in addition to D2 molecules, the gas phase over the deuterium fullerite sample heated to a temperature of 773 K contains CD4 methane and C6D6 benzene molecules. The deuterocarbon molecules are revealed in the gas phase even at 673 K.

Electron energy-loss spectra have been recorded for Ti, Si and TiSi 2 with E p = 100, 400 and 2000 eV. It is shown that the spectra may be used for the identification of compounds in the TiSi 2 /Si planar structure with thickness less than 0.4 nm.

Partial substitution of nitrogen by carbon in the metalloid sublattice of NbN possessing the NaCl structure leads to an increase in the temperature of the transition to the superconducting state. The changes in the local density of states on formation of NbCxN1-x alloys, which may be related to this increase, were investigated by Auger electron spectroscopy. The NbM5N2,3V, NbM5VV, CKVV and NKVV Auger spectra for NbCxN1-x over the range 0.06

Calculations of the electronic structures of the Cu4O4 and Cu6O6 clusters simulating oxygen dimers in the CuO2 sheets of the perovskite YBa2Cu3O7-δ were carried out within the discrete variational Xα-method (DVM-Xα). According to the results of calculations the chemical shifts of the O 1s core levels of oxygen dimers may change within the limits of 0–4.5 eV, depending on the distance between two dimer atoms. A comparison of the results with the experimental data allows the conclusion that the presence of oxygen dimers in the perovskite lattice may explain the appearance and the structure of a shoulder on the high-energy side from the main O 1s peak in X-ray photoelectron spectra (XPS) of the high-Tc superconductor YBa2Cu3O7-δ.

The catalysis method is used in the superconducting compound synthesis, taking ruthenium compounds as the catalyst. A number of samples of the composition YBa2−xCu3−yRuzO7−δ, where x = 0 to 0.2; y = 0 to 0.5; z = 0.1 to 0.9 is synthesized. The experiments show that the presence of Ru speeds up the YBa2Cu3O7−δ formation by ≈ 6 times. Superconductors with Tc above as well as below liquid nitrogen temperature are obtained depending on x, y, z. The TGA method, X-ray phase analysis, local X-ray spectral analysis, and X-ray photoelectron spectroscopy are used to study the YBa2Cu3O7−δ Ru containing system. It is proved that the Ru oxydation state is equal to eight. A new phase with semiconducting behaviour and the composition Y2Ba5CuRu2O17 is found. [Russian Text Ignored].

The article covers main principles underlying sanitary epidemiologic supervision over selection and exploitation of individual protective skin devices on objects of Federal Agency on Nuclear Energy. The authors consider radiation hazards influencing humans; provide specific medical and technical requirements to individual protective skin devices, which are monitored during preventive and current sanitary epide miologic supervision and determining peculiarities of use of individual protective skin devices by personnel working in radiation-hazardous conditions.

A study was made of the x-ray photoelectron spectra of Rh(I) and Rh(III) trifluoroacetate complexes. It was shown by using the Cls bond energies of the carboxylate carbon atom as a basis that bridging and monodentate coordination of the trifluoroacetate group could be distinguished with high resolution.

Results of X-ray photoelectron spectroscopy (XPS) and electron energy loss spectroscopy (EELS) studies are presented for the (ET)2C60 compound. It was established that XPS data correspond to small value of charge transfer in the complex. Loss function of (ET)2C60 was extracted from EEL spectra. Energy of main (σ+π) plasmon h ω=23.8 eV was determined.

Results from electron energy loss, X-ray photoelectron, and infrared spectroscopies are ptesented for the C 60 ·2S 8 compound. As one goes from C 60 to C 60 ·2S 8 , binding energy decreases by 0.5 eV, and ( σ + π ) plasmon energy decreases by 1.2 eV. Arguments for charge redistribution are performed.

The primary cosmic-ray electron flux between 3.5 and 80 BeV has been measured with a system composed of scintillation detectors separated by a lead absorber, and with careful discrimination against protons and multiply-charged nuclei. Observations are presented for two balloon flights made in the summer of 1966 at a latitude corresponding to a geomagnetic cutoff rigidity of abo~~t 2.5 GV. The results obtained are well represented by a power-law spectrum of the form: dN/dE = (125 f 20)E-3.0*0.08 electron/m2 s sr BeV between 3.5 and 80 BeV. A comparison is made with the results of other investigators.