Radio Control System Research Articles

A method to enhance the accuracy of radio frequency power measurements in particle accelerator high‐frequency systems

AbstractThis letter presents a method for accurately calculating radio frequency (RF) power in a standing wave transmission line system. The proposed approach utilizes two directional couplers in conjunction with a low‐level radio frequency control system. RF power is determined through the application of proposed equations derived from amplitude and phase measurements of coupling signals obtained from the two directional couplers. Experimental validation of the method is conducted using two directional couplers with directivities of 26 and 28 dB, respectively, operating at 162.5 MHz across the entire wavelength. Results indicate that employing a single directional coupler yields average power errors of approximately 6.6% and 5.8%, respectively. However, by implementing the proposed method, the measurement error can be reduced to approximately 1.0%.

Tracking and Disturbance Suppression of the Radio Telescope Servo System Based on the Equivalent-Input-Disturbance Approach

This paper presents a composite control algorithm for the radio telescope servo control system to address the target tracking and matched/mismatched disturbance suppression problems. The algorithm consists of the equivalent-input-disturbance (EID) approach and the optimal control method. An EID estimator is developed using the difference between the estimated output of the state observer and the measurement output and then the estimate of the EID is fed forward into the control input to reject the disturbance. A cost function with clear physical meaning is selected and the weighting parameters are adjusted for the optimal controller to improve tracking performance. Considering the nonminimum phase characteristics of the radio telescope system, the state observer gain is computed using the linear matrix inequality (LMI) method. The system stability is analyzed using the small gain theorem, and the linear quadratic regulator (LQR) control method is utilized to determine the state feedback gain. Finally, the composite controller is designed for an identified telescope model. Simulation results show that for the tracking performance, the settling time of proposed method is 1.13 s and reduces by about 0.32 s and 0.87 s than that of the ADRC controller and PI controller, respectively. For the antidisturbance performance, the RMS value and the maximum error of the proposed method are 0.0039 and 0.0128, which are 42.86% and 40.38% of the ADRC controller and 30.71% and 27.77% of the PI controller, respectively, which indicates that the proposed method has better control performance. In addition, the proposed controller has certain robustness to systematic parameter perturbations.

POWER SUPPLY OF RING ANTENNA USING DIRECTIONAL COUPLERS

Context. The circular polarization of radio waves is used in various electronic systems. This includes, for example, space communications stations, some radio relay communication systems, radar stations, data transmission systems and others. The characteristics of radio wave propagation are studied by using electromagnetic waves separated by circular orthogonal polarization in radiomonitoring and radiocontrol systems. Compared to other antenna types, circularly polarized antennas, such as rings, have superior design simplicity and excellent electrodynamics properties.
 Objective. The objective of this study is to analyse the characteristics and application of directional microstrip couplers for supplying power to ring antennas.
 Method. To better the performance of microstrip ring antennas, the reasons for their limited operating frequency range are analysed. These causes include the frequency-dependent parameters of the coupler, errors in calculating the directional coupler circuit, and radiation from asymmetric strip lines. To understand how supply lines, affect antenna characteristics, correlations between radiation fields determined in both its coordinate system and that of the primary axis are taken into account.
 Results. An analysis of the dependence graphs of the main characteristics of ring microstrip antennas with intricate power supply circuits for directional couplers and comparison with similar characteristics for simple circuits revealed that the shape of the radiation pattern in the higher radiation hemisphere became symmetrical about the axis, especially when symmetrically supplying the ring with branch-line couplers. The frequency band has also widened, at which there was an acceptable degree of deviation in the ellipticity coefficient from unity.
 Conclusions. The simulation results of microstrip ring antennas with power lines connected to directional couplers of different types showed that supplying the ring antenna with electricity via the directional coupler ensures circular polarization for the emitted electromagnetic waves. Additionally, the range of operating frequencies where there is only a small discrepancy in ellipticity coefficient remains at an acceptable level of –3 dB is quite broad. By utilizing directional branch-line couplers to power a ring antenna, it is possible to simultaneously emit both right and left circularly polarized waves with the same antenna.

SPECTRAL-COVARIATION METHOD OF CLASSIFICATION OF RADIO SIGNALS

The paper proposes a high-performance method of radiosignal classification based on spectral-covariance evaluation of signals. At the same time, multi-stage processing of overlapping subsequences of readings of the investigated radiosignal in the time and frequency domain is carried out. At the first stage, it is proposed to evaluate the parameters of the radiosignal based on the found power spectral density of the investigated signal. To determine the spectral density of the radiosignal, subsequences of readings obtained from the array of input readings of the investigated signal are formed. The maximum shift between two adjacent subsequences is chosen, that is, the initial realization of the signal is presented in the form of overlapping subsequences. Taking into account that two adjacent subsequences have part of common processed readings, the paper proposes an expression that for each new subsequence of input readings would take into account the coefficients of the discrete Fourier transform, which were determined for the previous subsequence of the input signal. During the following stages, the shape of the spectrum of the analyzed radiosignal is compared with the spectrum samples specified by the operator of the radiocontrol system. Comparison of the spectrum of the investigated radiosignal and the spectral mask is based on the determined correlation coefficient. The approximation of the value of the correlation coefficient to unity characterizes the degree of linear relationship between the spectrum of the signal and the mask. This makes it possible to determine the type and positions of radiochannels based on the obtained sequence of correlation coefficient values for different shifts of the spectral mask. The analysis of the effectiveness of the proposed method confirmed that thanks to the developed method, it is possible to increase the productivity of the spectral-covariance evaluation of radio signals by 2.0Г·8.9 times, depending on the volume of the analyzed implementation of the radiosignal and the number of overlapping subsequences. The maximum performance factor is achieved when the initial implementation of the radiosignal is divided into 64 overlapping subsequences. The proposed method can be used in automated radiotechnical control systems to monitor the radiosituation in real time.

Compact and efficient radio frequency digital feedback control system for accelerator applications

The digital feedback (DFB) setup employed in a low-level radio frequency (LLRF) control system is crucial to ensure RF field stability in accelerating cavities, thus guaranteeing successful operation. To this end, a novel in-house and multi-purpose prototype DFB setup was developed for multiple applications at the Japan Proton Accelerator Research Complex (J-PARC). Being efficient, low-cost, and compact is key to achieving a cost-effective system that fulfills the performance specifications. It also reduces the production and maintenance costs of future DFB setups. A field-programmable gate array (FPGA)-based design with a digital signal processing (DSP) function uses an analog in-phase/quadrature-phase (I/Q) demodulator for RF-to-baseband signal conversion and an I/Q modulator to generate RF power. This arrangement compensates for RF phase fluctuations and amplitude modulations by employing a proportional and integral (PI) feedback controller. In addition, systematic errors are minimized by applying a hardware-error-compensation process. The system was utilized to conduct high-power tests on the interdigital H-mode drift-tube linac (IH-DTL) cavity of a muon linac for short RF pulses. The setup was also tested on a buncher cavity (Buncher-2) in the J-PARC linac, achieving efficient performance for longer RF pulses. The stability of the RF accelerating field in the IH-DTL was achieved at ±0.25% peak-to-peak (pp) in amplitude and ±0.36 degree pp in phase. For the Buncher-2, the amplitude stability of ±0.18% pp and phase stability of ±0.13 degree pp were obtained. Therefore, this DFB setup can be used to conduct high-power tests of RF cavities and klystrons. This study discusses the design aspects of a cost-effective DFB system and reports high-power measurements.

Formation of Programming Skills among Students of Scientific, Technical and Natural Science Areas of Training Using the Arduino Platform

The problem of improving the educational process of students of scientific, technical and natural science areas of training is one of the relevant aspects of modern pedagogical research. During training, it is necessary to apply new approaches, educational technologies and techniques in order to prepare graduates who are able to independently solve complex scientific, technical and engineering design tasks in the process of modern production. Programming is a universal tool for modeling objects and processes, as well as a powerful tool in developing the thinking of students of scientific, technical and natural science fields of training. The article discusses the issues of formation of programming skills of students based on the use of the Arduino platform. The professional standards are analyzed, the main contradictions of the existing system of training future bachelors in the field of radio electronics and control systems are revealed. The method of organizing effective programming training based on the use of the Arduino platform is presented. The criteria and indicators of the levels of competence formation are given. The results of an experiment on the implementation of the described methodology of teaching programming on the basis of the I.N. Ulyanov Chuvash State University are shown. Using the chi-square criterion, statistical processing of the results of a pedagogical experiment was performed, which convincingly proves that when using the Arduino platform, most students have reached high and advanced levels of programming skills formation.

The Augmentation of a Flight Control Mechanism for a Hybrid Fixed-Wing VTOL Drone for Parcel Delivery

Several companies are experimenting with multicopters drones to deliver packages to customers. Although they are less aerodynamically efficient than fixed-wing aircraft, their ability to do the vertical take-off and landing (VTOL) makes them ideal for delivery services. In this study, two methodologies will be used to build the drone which is software simulation and experimental approach. Software such as SIMNET is used to simulate and design an electronic operation of the drone while Mission Planner is used to setup the flight controller. Electronics layout is done prior to ensure a clear sight of work, components and information through the software. The flight controller used is called Pixhawk which is an open hardware mainly used for drone. The radio control system is also setup to be used as the link to control the flight controller. Flight tests were also performed to study the behavior of the drone at various percentage of throttle. At 60 percent throttle, the drone yaws continously to the left at 63.43 degrees at 4.879 degrees per second during test flights. With a payload weight of 516g, it tilted to the front nose down, with support provided at the tip of the left wing. With more design and calibration advancements, experimental findings that are similar to theoretical outcomes might be attained. Flight data after each test flight is extracted from the software and analysed for further improvement. The fabrication of complete prototype could not be finished within the stipulated time due to a delay in acquiring new parts such as propeller due to a problem, as well as procuring the appropriate material for the wing. A test of the drone motions including roll, pitch, and yaw, is also carried out using flight charts to validate the suggested design parameter. The drone tends to fly better with the motor turning with the same orientation rather than turning with different orientation due to better stability.This flight chart allows users to choose the best design parameters by determining the length of the wingspan, motor RPM, and propeller diameter that are expected to meet the performance requirements in these three flying motions. The procedure for estimating the drone's battery usage has also been presented in the flight chart.

Principles of construction and basic characteristics of perspective noiseproof course-glide system

Introduction: based on the analysis of the known literature, it is shown that modern course-glide systems have disadvantages associated with the presence of carrier signal generators in them, the lack of frequency and spatial selection of the signal and interference. The purpose of the work: to develop the principles of constructing a promising noise-resistant course-glide system based on the joint use of inversely directed reflectors, aperture antennas and electrodynamic controlled layered inhomogeneous structures. The controlled layers are periodic lattices of conducting elements with nonlinear elements included in their discontinuities. Uncontrolled layers are lossless dielectric layers and periodic lattices of conducting elements. Materials and methods: algorithms for parametric synthesis of controlled and uncontrolled layers of electrodynamic inhomogeneous structures, experimental methods for analyzing monostatic and bistatic backscattering diagrams, experimental methods for determining the frequency characteristics of electrodynamic inhomogeneous structures in various states of controlled layers. Results: the possibility of designing a promising course-glide system with specified characteristics that provide a new method of radio communication without using its own carrier signal generator is shown. Conclusion: the proposed course-glide system can be used to solve many problems that cannot be solved with the help of a known course-glide system. Such tasks include imitation of moving and stationary objects of weapons and military equipment; covert transmission of information in the absence of its own carrier signal source; radio-electronic suppression of radio communication and control systems, radar control systems for weapons of a likely enemy.

Improving UAV Radio Control System with 433 MHz Radio Wave Using Lo-Ra based on QCZEK Model Communication System

UAV must have a reliable control system considering the UAV is an unmanned vehicle that relies on human control on the ground. Most of control system used in UAVs uses a 2.4 GHz as it frequency. This frequency has disadvantaged for UAV because it is mainly used for Wi-Fi communication system so when users of UAV’s fly in urban areas where full of Wi-Fi system, there will be interference within UAV control system and Wi-Fi, so failsafe will often occur. From the theory, different frequencies produce different criteria for radiofrequency communication system to synchronize and manage and secure communication between transmitter and receiver. In this study, we will discuss the application of 433 MHz frequency for the control system for UAV. The goal of this research is to establish a reliable control system of UAV when used for the long-range mission. To make this control system, we use the Lo-Ra module with STM32 based Microcontroller designed for QCZEK TX/RX model communication. After several testing on the ground and the air, the purpose system serve 14 % longer distance than TBS system or market build system and 6 times longer distances than 2.4Ghz frequencies.

Model of data flow control subsystem of the manet class mobile radio network control system

The article proposes a model of the data flow control subsystem of MANET class mobile radio control system to evaluate the effectiveness of the model, which will be built based on the developed methods and techniques (corresponding units). The essence of the model is to apply appropriate methods of DFCS control, which interact with each other and other functional subsystems within the operation of the subsystem units and their interaction, based on the target function. To ensure effective control of a mobile radio network in conditions of frequent changes of the situation (operational, tactical, communication, etc.) is possible only if there is a nodal control system capable of making control decisions in conditions of uncertainty. In addition, provision of the ability of mobile radio networks to self-organization, as well as adaptation of its nodes to different operating conditions requires the presence of a training subsystem as part of the node control system. To ensure effective control of a mobile radio network in conditions of frequent changes of the situation (operational, tactical, communication, etc.) is possible only if there is a nodal control system capable of making control decisions in conditions of uncertainty. In addition, provision of the ability of mobile radio networks to self-organization, as well as adaptation of its nodes to different operating conditions requires the presence of a training subsystem as part of the node control system. Considering the peculiarities of the functioning of MANET class radio networks, the article proposes to intellectualize the control processes by using knowledge processing technologies in the construction of a node control system. Based on the integrated use of fuzzy logic and neural networks, the probabilities of violations are considered, which, depending on the parameters of the state of the nodes, allow selecting the required value of the violation of the state of the network. Unlike existing models that are used in computer or fixed networks that do not require resource-intensive structure, in this model it is proposed to develop the structure of the DFCS to the requirements and features of usage in the mobile radio network. The application of the model will allow: to simplify and improve the structure of the construction of the data flow control subsystem; to process incomplete, inaccurate, unpredictable, different in its physical content data; to reduce the time of making a control decision. The further directions of research will be the development of the method of connectivity of the elements of the data flow control subsystem of the mobile radio network control system.

Codes for Multiple-Access Asynchronous Techniques

This article discusses asynchronous techniques with spreading sequences (codes) that are statistically uncorrelated for arbitrarily random starting points. We provide improved codes for the spread-spectrum multiple-access asynchronous techniques. The article provides methods for generating improved codes, as well as estimates of their parameters. We investigate the cross-correlation of codes for arbitrarily random starting points. The comparative analysis shows that with a slight increase in the correlation modulus, we can significantly increase the cardinality of the spreading codes. This useful property can be used in future radio control systems and future smart grids to implement soft capacity, i.e. the base station can increase the subscriber capacity with a slight decrease in the quality of service.

Методика побудови первинної матриці похибок радіотелескопа РТ-32 в автоматизованому режимі

2020 was the year of introduction of the Ukrainian new generation radio telescope RT-32 into the experimental operation. The test results of maser hydrogen and hydroxyl lines obtained during the experimental operation confirmed the correctness of the calculations and technological solutions of Ukrainian scientists and manufacturers Consortium. One of the further development directions of RT-32 as a radio astronomical research tool is to increase the accuracy of pointing the radio telescope to radio astronomical sources. One of the further development directions of RT-32 as a radio astronomical research tool is to increase the accuracy of pointing the radio telescope to astronomical radio sources. The latter is to be achieved by automating the processes of guidance error matrices formation and their integration during the observations. The formation of such a matrix presupposes taking into account the structural features of the antenna system and weather condition. The paper presents the results of geodetic measurements of the antenna system surface on different elevation angle, construction of the 3D model of the reflector. The method of constructing the error matrix, which at this stage of research provides the necessary simplicity of perception and interpretation of the obtained results by the human operator, is proposed. The results of the developed method verification using reference radio sources are given and the error matrices of elevation and azimuth pointing (dimension 81x81 elements) obtained with the use of said method are presented. The introduction of the results presented in the article into the radio telescope control system allowed increasing the accuracy of RT-32 radio telescope pointing in the C- and K- bands to the value of ~36″. This work partially was supported by Latvian Council of Science project "Joint Latvian-Ukrainian study of peculiar radio galaxy “Perseus A” in radio and optical bands. Nr: lzp-2020/2-0121".

Trends in Architecture and Middleware of Radio Telescope Control System

The control system is the central control unit of the radio telescope. It is used to monitor, control, coordinate, and manage software and hardware systems so as to satisfy the requirements of high-precision control in astronomical observation of radio telescope. The control system architecture is the foundation for the implementation of the control system, which determines the stability, scalability, and maintainability of the control system. Furthermore, the architecture design of the control system is closely geared towards the technological development of radio telescope and computer software architecture. In this article, we analyze the characteristic of the control system of a radio telescope in various steps and discuss the development of their architecture and middleware framework. System architecture and middleware framework of control system also serve as a useful reference for the design of other radio telescope control systems.

Aviation radio control systems as complex technical systems. Part 1. Analysis of the possibilities of multicriteria optimization

The need to take into account the increasing requirements for expanding the field of application conditions, taking into account an increasingly wide range of possible conditions, increasing requirements for the volume and reliability of the information used, combined with increasing requirements for improving the efficiency of operation, predetermined the emergence of a new type of information management systems, called "complex technical systems" (CTS). In general, the CTS is understood as a set of functionally related control and information subsystems united by a common goal of joint solution of a group of tasks. The most striking example of CTS is aviation radio control (RC) systems, which are able to solve the general task of destroying targets in several stages, using various methods of route control and guidance on them in conditions of high initial uncertainty due to a variety of possible objects of influence of varying degrees of importance and the random nature of their spatial location. At the same time, the task of destroying objects of the opposing side is solved, as a rule, in several stages, including long-range (command), short-range guidance (homing) and the use of weapons. It should be emphasized that the choice of indicators of excellence that reflect various aspects of the functioning of the CTS (aircraft RC systems) is by no means a trivial task. Within the framework of the "system – environment" approach, which takes into account the specific conditions of the use of the CTS, in addition to performance indicators that reflect the degree of compliance of the system with its purpose, such indicators as functional stability (survivability), dynamism and informativeness are increasingly in demand, which, as a rule, contradict each other. It should be noted that due to the heterogeneity of the tasks being solved and the inconsistency of the requirements, it is necessary to take into account the need to use a multicriteria approach to the synthesis of control methods and information support algorithms. However, the methods of multicriteria optimization used in practice have a number of significant drawbacks that make it difficult to use them in the development of promising CTS (RC systems). At the same time, it is very tempting to use the mathematical apparatus of the statistical theory of optimal control (STOC) for multicriteria optimization of the CTS, which allows to avoid the above disadvantages to some extent. The expediency of using STOC for solving multicriteria problems is due to the fact that the very formulation of the STOC problem and the resulting optimization procedures already contain a solution to the two-criterion problem of obtaining a system that is jointly the best in both accuracy and costeffectiveness of management. The analysis of various approaches to solving multicriteria problems has shown that the most rational is to reduce them to a singlecriteria problem with further use as a basic variant of local STOC optimization.

Aviation radio control systems as complex technical systems. Part 2. Multicriteria optimization based on a local modification of the statistical theory of optimal control

The analysis of the known modifications of the statistical theory of optimal control (STOC) in the application to the problem of multicriteria optimization of radio control (RC) systems showed that for its solution, a variant that takes into account the measured perturbations in the state model can be used as a basis. The physical meaning of this approach is that of all the alternatives, one is chosen, conditionally the main one, for which a state model is formed. The remaining participants in the general synthesis procedure are considered as a set of perturbations acting on this model. Accordingly, in the quality functional used, the terms that ensure the minimization of these perturbations should be taken into account in the form of an additional linear combination of quadratic forms. Management that minimizes such functionality, to one degree or another, will be jointly the best for the entire set of requirements. The choice of the local optimization option is based on the desire to avoid the need to solve a very computationally expensive twopoint boundary value problem, which is characteristic of the optimization procedures of systems for the entire time of operation, and to ensure invariance to the time of operation. The analysis of the obtained control law allows us to formulate the following conclusions. The control contains two terms, one of which implements the main purpose of the system, providing an approximation of the real state to the required one, and the second takes into account the influence of alternative requirements. The optimized system should include optimal filters that form estimates of the necessary state coordinates, and a controller that forms a control signal. The obtained result indicates that it is possible to optimize management within the framework of solving a multicriteria task (MCT) without solving a complex two-point boundary value problem. If necessary, you can choose another version of the main model with a different set of auxiliary tasks and the corresponding functionality as the main task, with a different control option. In the process of comparing the obtained control options, you can choose the best solution to the general optimization problem. Considered as an example, the law of controlling a group of three initially geographically separated and moving in different directions unmanned aerial vehicles used for radar monitoring of large areas of the earth (water) surface, which at the same time should provide the collection of the group, the required trajectory of its flight and the required topology of participants implementing a given control band, confirmed the possibility of solving the MCT based on STOC.

Автоматизированная радионавигационная система диспетчерского управления пассажирским транспортом АСУ-Навигация

Автоматизированная радионавигационная система диспетчерского управления пассажирским транспортом АСУ-Навигация

НАУЧНО-ТЕХНИЧЕСКИЕ ПРЕДЛОЖЕНИЯ ПО ИНФОРМАЦИОННО-АНАЛИТИЧЕСКОМУ ОБЕСПЕЧЕНИЮ КОМПЛЕКСОВ РАДИОМОНИТОРИНГА

Introduction: within the framework of the scientific direction on improving the information and control systems of radio monitoring complexes, the issues of forming the structure and content of information resources that ensure the solution of the problems of collecting, processing and presenting radio monitoring data are considered. The starting point was the requirements for information management systems, the basis for the implementation of which is to find a rational structure of information resources and develop mechanisms for their interaction, filling and updating. Purpose: on the basis of an analysis of the requirements for radio monitoring complexes information and control systems, develop scientific and technical proposals for the implementation of scientific developments on the formation of their information resources that ensure the fulfillment of these requirements. Results: the target function of the system, indicators of the quality of its functioning have been determined. The article presents the results of constructing a conceptual model of a single information resource of a radio monitoring complex as a set of structural, functional and ontological models. The main structural elements are the storage of radio monitoring data coming from technical means of detection, direction finding of radio electronic means, a database of indicative descriptions of radio monitoring objects, a factual information resource, a database with the results of processing radio monitoring data, as well as directly processing algorithms. The issues of filling information resources, determining the frequency of their updating are reflected. The composition of the algorithms for operational (current) and thematic (deferred) processing of radio monitoring data is concretized, the main tasks of the control subsystems and the provision of information and control systems are detailed. The software architecture of information support of radio monitoring complexes is proposed. The application of the integrated service bus technology as a metasystem basis of information resources is shown. Conclusions are made about the applicability of the developed scientific and theoretical provisions in practice, examples of the construction of software that implement them are shown. Discussion: the research results can be used in the formation of information resources of multi-level systems and radio monitoring complexes, the information process in which involves multi-stage data processing and their presentation in real time to various consumers.

Метод автоматичної побудови матриці похибок радіотелескопа РТ-32. Методика автоматичного оцінювання похибок наведення

On March 15th, 2021, scientists of the National Space Facilities Control and Tests Center and the Radio Astronomical Institute of the National Academy of Sciences of Ukraine carried out preliminary observations with the Ukrainian new generation radio telescope RT-32 (Zolochiv, Lviv region). The extragalactic radiation of radio galaxy 3C84 (Perseus-A), masers from the galactic molecular cloud W3, radio emission of methanol maser from the galactic radio source G188.946 + 0.886 were observed and successfully recorded. Observations were performed as training in the framework of preparation for the launch of a joint Ukrainian-Latvian radio astronomy project lzp-2020/2-0121. The results of the observations confirmed the world level of RT-32 radio telescope characteristics, the efficiency of the primary error matrix and revealed several shortcomings in the functioning of the tracking system. It was found that the primary tracking error matrix has insufficient discreteness and contains errors of the first and second types. In the article, we present a method of automatic construction of the radio telescope error matrix according to the data of a radiometric receiver and receivers-recorders. The method of construction provides automatic processing of the obtained radiometric data. The results of verification of the developed method using the reference radio sources of different types and the elements of tracking errors’ matrix by the elevation and azimuth obtained when using it are presented. The results obtained with the proposed method were included in the radio telescope control system and allowed us to increase the aiming accuracy of the RT-32 radio telescope.

MECHANISM OF ENSURING SAFE UAV MOVEMENT UNDER THE CONDITIONS OF RADIO ATTACKS

Purpose. The aim of the article is to reveal the mechanism of formation of safe UAV movement in the conditions of radio attacks. Methodology. Scientists from Ternopil National Technical University named after Ivan Pulyuy have consistently developed and studied several mechanisms for the formation of safe movement of unmanned aerial vehicles in radio attacks in order to create a perfect model with which to launch UAVs in areas with high radio attack. As a result of previous work, the mechanism of formation of safe movement of UAVs in the conditions of radio attacks based on methods of increasing the stability of providing information about the route of the unmanned aerial vehicle in the use of REP and air defense systems. Results. The article reveals the mechanism of formation of safe movement of unmanned aerial vehicle in the conditions of radio attacks. Analysis of known solutions in the field of increasing the stability of the control path of unmanned aerial vehicles and electronic suppression demonstrated the relevance of the problem of forming flight routes of unmanned aerial vehicles bypassing opposing enemy areas, taking into account the use of air defense and electronic warfare. The authors emphasize that most drone control tasks are now automated due to their high complexity and versatility. An automated control system operating under the control of a human operator is used as a control factor on an unmanned aircraft. It is emphasized that the main threats to unmanned aerial vehicles in modern conditions are the possibility of their destruction by air defense systems, as well as disruption of the radio communication and control system between the control center and the UAV by electronic suppression. The need for constant tracking of UAV flight by transmitting commands from the launcher is revealed. It is also emphasized the low level of automation of the onboard control system of the unmanned aerial vehicle and the inability to make adequate decisions on information received from onboard sensors in complex situations that require constant monitoring of UAV flight by a human operator. Scientific novelty. For the first time the functional scheme of the UAV recognition mechanism in the conditions of radio attacks is developed and the mechanism of formation of safe movement of the UAV in the conditions of radio attacks which is based on three basic techniques is defined. The first method is the method of clustering the flight zones of an unmanned aerial vehicle according to the degree of control stability. Based on the second method, the authors propose a method of forming the routes of UAV flights, taking into account the location of air defense and electronic warfare. The last link is the method of assessing the stability of providing information about the route of the unmanned aerial vehicle in terms of the use of air defense and electronic warfare. Practical relevance. The results of the work can be implemented in the process of forming the safe movement of UAVs in the conditions of radio attacks. Keywords: unmanned aerial vehicle; air traffic control; space; security; flight.

An Inspection Robot for Belt Conveyor Maintenance in Underground Mine—Infrared Thermography for Overheated Idlers Detection

It is well known that mechanical systems require supervision and maintenance procedures. There are a lot of condition monitoring techniques that are commonly used, and in the era of IoT and predictive maintenance one may find plenty of solutions for various applications. Unfortunately in the case of belt conveyors used in underground mining a list of possible solutions shrinks quickly. The reason is that they are specific mechanical systems—the typical conveyor is located in the mining tunnel and its length may vary between 100 and 1000 m. According to mining regulations, visual inspection of the conveyor route should be done before it will start the operation. On the other hand, since environmental conditions in mining tunnels are extremely harsh and the risk of accidents is high, there is a tendency to minimize human presence in the tunnels. In this paper, we propose a prototype of an inspection robot based on a UGV platform that could support maintenance staff during the inspection. At present, the robot is controlled by an operator using radio however, we plan to make it autonomous. Moreover, its support could be significant—the robot can “see” elements of the conveyor route (RGB camera) and can identify hot spots using infrared thermography. Moreover, the detected hot spots could be localized and its position can be stored together with both types of images. In parallel, it is possible to preview images in a real-time and stored data allow analysing state of conveyor system after the inspection mission. It is also important that due to radio control systems, an operator can stay in a safe place. Such a robot can be classified as a mobile monitoring system for spatially distributed underground infrastructure.