On-board Equipment Research Articles

Status of the H2020-ROBOMINERS Prototype

This article presents the current status of the H2020-ROBOMINERS project with focus on the prototype to be developed. The aim of this project is the development of a small-scale mining robot, which will be capable of exploring difficult to access deposits with the ability of selective mining underground, under water, and in slurries. Considerably low weight and power are challenges to be overcome. Environment-friendliness is secured by powering the entire robot water-hydraulically. Core element of the robominer is the main module, in which the locomotion and powering system will be implemented. Additional elements in the robot are sensors for navigation and perception and a production tool to excavate small amounts of material. The locomotion system consists of an Archimedes-screw mechanism, which can be extended in radial direction and used as grippers inside a tunnel to increase its traction capacity. Selective perception tools help the mining robot navigate in harsh terrains and find the ore. A small-scale longitudinal part-face cutter head has been selected as an excavation tool. This cutter head has been tested extensively in the laboratory by performing cutting tests with several rock samples. The performance allows a continuous excavation of soft rock material (successful tests with reasonable excavation rate up to a uniaxial compressive strength of 30 MPa). The mined ore is then slurrified and transported to a processing station. On-board analysis equipment using specializsed sensing systems allows the robot to analyse the slurry composition in real-time. The demonstration and final test of the full-scale prototype are planned in an open-pit oilshale mine. Eventually, the project will serve as a guideline for future mining robots including feasibility studies of different robot designs, potential mine layouts and mining scenarios as well as various excavation tools for different rock conditions.

Basic aspects of topological technology of automated on-board equipment layout in space vehicle compartments using the example of “Yantar-2k” Earth remote sensing space vehicle

The article presents the theoretical foundations of automated design of on-board equipment layout in spacecraft compartments in terms of topology. The purpose of the work is to create a flexible arrangement model that would allow solving the problem for any configuration of the structure, taking into account the engineering and operational restrictions imposed on the objects located in a limited space. The technology is formalized according to the methods of the foundations of topology and in this work is demonstrated for a two-dimensional case by comparing it with a reference design-layout scheme. The functional, installation, dimensional, thermal, vibroacoustic requirements are taken into account with the mass-centering restrictions of the layout. In the course of the study, a new approach to describing the design process of assembling on-board equipment was obtained, which can be fully digitized and then integrated into known computer-aided design systems. It has been verified using the example of the power supply system of the Yantar-2k spacecraft.

Optimization of a land vehicle suspension subjected to a buried charge explosion

Improvised Explosive Devices (IEDs) represent a serious threat to vehicles. These IEDs can partially or fully damage the vehicle and the onboard equipment and, threaten the lives of its crew. To protect against these devices, modifications to specialized vehicles are made in different parts. Among these latter, the present work focuses on the effects of the suspension system on the dynamic response of the vehicle. The behaviour of a McPherson suspension system of a light vehicle is numerically studied in order to optimize the dimensions of selected components. Three models based on different approaches are developed. The first is based on an Arbitrary Lagrangian Eulerian (ALE) formulation with fluid-structure coupling, which gives a more realistic representation of the blast phenomena. However, it needs significant calculation time and computational power. The second is a simplified, purely Lagrangian, model which requires less computational resources but includes several assumptions. The third model is based on a meta-modelling approach. This latter is used to optimize the dimensions of selected sub-systems of the vehicle suspension via a genetic optimization algorithm.

Fault Prediction of On-Board Train Control Equipment Using a CGAN-Enhanced XGBoost Method with Unbalanced Samples

On-board train control equipment is an important component of the Train Control System (TCS) of railway trains. In order to guarantee the safe and efficient operation of the railway system, Predictive Maintenance (PdM) is significantly required. The operation data of the on-board equipment allow us to build fault prediction models using a data-driven approach. However, the problem of unbalanced fault samples makes it difficult to achieve the expected modeling performance. In this paper, a Conditional Generative Adversarial Network (CGAN) is adopted to solve the unbalancing problem by generating synthetic samples corresponding to specific fault labels that belong to the minority classes. With this basis, a CGAN-enhanced eXtreme Gradient Boosting (XGBoost) solution is presented for training the fault prediction models. From the pre-processing to the field data, artificial fault samples are generated and integrated into the training sample sets, and the XGBoost models can be derived with multiple decision trees. Both the feature importance sequence list and the knowledge graph are derived to describe the characteristics obtained by the models. Filed data sets from practical operation are utilized to validate the proposed solution. By comparison with conventional machine learning algorithms, it can be found that higher accuracy, precision, recall, and F1 scores, which are up to 99.76%, can be achieved by the proposed solution. By involving the CGAN strategy, the maximum enhancement to the F1 score with the XGBoost approach reaches 6.13%. The advantages of the proposed solution show great potential in implementing equipment health management and intelligent condition-based maintenance.

The main provisions of the methodology for ensuring the resistance of the onboard equipment of spacecraft to the effects of the radiation effects of outer space

In this paper, the problematic issues of ensuring the resistance of the onboard equipment of spacecraft to the effects of ionizing radiation from outer space, which significantly limits the period of active existence of the spacecraft, are considered. The paper describes the methodology) for ensuring radiation resistance, developed by the specialists of JSC ISS. The result of the work done is to ensure the guaranteed performance of the target function by spacecraft with long period of active lifetime of 15 or more years. Among the complex of outer space factors affecting the spacecraft, ionizing radiation of outer space is the main factor limiting the period of active existence. Exposure to energetic particles of ionizing radiation from outer space causes degradation of the electronic component base, which leads to failures and malfunctions of on-board equipment and degradation of its functional surfaces. Ensuring the radiation resistance of a spacecraft (SC) is a complex task, one of the stages of which is to determine the radiation resistance of components that complete the on-board equipment. As a result of accumulated experience in conducting radiation tests and analysis of the results, specialists of JSC ISS developed a methodology that allows to guarantee the radiation resistance of the spacecraft under conditions of tight production deadlines and optimized costs.

Моделирование процесса определения технического состояния тяговых электродвигателей электровозов 2ЭС6

Or positive results in reducing the number of failures of electric traction engines, predictive diagnostics in operation is proposed. The development of malfunctions in electric traction engines directly affects the registration of analog signal values by on-board equipment. Some distinctive criteria have been identified by which the technical condition of electric traction engines can be assessed. The previously developed algorithm for searching for electrical damage has been improved. The presence of a difference in armature current between adjacent bogies and pairs of the same type of electric traction engines is pointed out, the dependence between a serviceable and faulty electric traction engine in the form of discrepancy in correlation coefficients is revealed. All the revealed conditions are added to the algorithm for determining the technical condition, the processes of which are built on the KNIME intelligent analysis platform. The process of determining the technical condition with the output of the result on the serviceability / malfunction of the electric traction engine is modeled. A pair of electric traction motors with a potential malfunction is also identified. The relative modeling error, which is at an average level, allows us to partially solve the problem of occurrence of failures of electric traction engines during operation. The application of the model along with the existing methods improves the quality of predictive diagnostics of modern locomotive equipment.

Study of determining methods and preventing emergency conditions for the flight of an pilotless vehicle in case of failure of onboard equipment

The analysis of the influence of internal and external factors affecting the flight safety of a pilotless vehicle is carried out. The assessment modeling of the aviation accident treat in failures case of the pilotless vehicle onboard equipment and the deterioration of the flight weather conditions is carried out. A method to prevent the threat of the emergency situation under consideration when controlling a pilotless vehicle, taking into account the peculiarities of its operation, is proposed. The obtained results make it possible to evaluate the possibility of applying methods for assessing and preventing the threat of an aviation accident during the flight of a pilotless vehicle. The proposed methods and simulation results are used in the design of pilotless vehicles, as well as onboard devices for ensuring aircraft flight safety. Keywords pilotless vehicle, onboard flight safety management system, assessment of flight conditions, counteracting the threat of an aviation accident, operator decision support system

Possibility of unification of requirements for radiation resistance for spacecraft with different operating conditions

During the period of active lifetime in different types of orbits, spacecraft are exposed to various factors of outer space. Die main factor influencing the performance of electronic equipment is the ionizing radiation of outer space. The main effect associated with the impact of the ionizing radiation of outer space on the spacecraft (dose effects), in its physics, is determined by the radiation dose absorbed in the components of the electronic component base and construction materials during the entire lifetime. This effect explains the failures in the operation of radio-electronic equipment due to the degradation of the parameters used in the products of the electronic component base and materials. Calculation of levels of exposure to absorbed doses depending on various parameters of the orbit is a necessary and important task for ensuring the functioning of the spacecraft during a given lifetime, since calculations of radiation resistance are based on the levels of exposure in orbit. The key, from the point of view of minimizing mass protection and the scope of testing of critical electronic component base products, is to carry out calculations taking into account the design features of the spacecraft and on-board equipment. In addition to taking into account the design of the spacecraft and the spacecraft, an important aspect when calculating the radiation resistance is taking into account the relative position of the spacecraft in the spacecraft. This article considers the possibility of unifying the requirements for radiation resistance for spacecraft with different operating orbits and lifetime, as well as the possibility of carrying out a unified calculation without taking into account the design features of the spacecraft, spacecraft and relative position within the spacecraft.

Research on impact reduction of flexible boundary particle damping honeycomb plate based on discrete element multi body dynamics coupling

<abstract> <p>The exposed platform is the main component of precision instruments such as pyrotechnic separation devices and load adapters, and its dynamic response characteristics are a key factor affecting the stability of aircraft. When the pyrotechnic separation device explodes, the exposed platform will be subjected to high-frequency, transient and high-order pyrotechnic impacts. High order pyrotechnic impacts can easily cause damage to sensitive components in onboard equipment, resulting in incalculable losses. Filling the honeycomb core cavity inside the exposed platform with a flexible boundary particle damper can effectively attenuate the pyrotechnic impact load after experiencing a large number of discontinuous structures. A numerical model of a flexible boundary particle damper and an exposed platform honeycomb panel was established through the coupling of discrete element and multi body dynamics. The effects of particle material, particle size, filling rate and flexible boundary film thickness on the impact reduction performance of the flexible boundary particle damper were analyzed, and the optimal characteristic parameters of the flexible boundary particle damper were obtained. The impact test was conducted on the honeycomb panel of the exposed platform using a light gas gun impact experiment, verifying the impact reduction effect of the flexible boundary particle damper and the accuracy of the numerical model. Finally, a pyrotechnic impact experiment was conducted on the exposed platform honeycomb panel with the optimal parameter flexible boundary particle damper. The experimental results showed that the impact reduction effect of the flexible boundary particle damper with this parameter reached 55.52%.</p> </abstract>

On-line Monitoring of Instantaneous Over-voltage Intelligent Monitoring of EMUs

Since high-speed EMUs have high requirements for the reliability of the traction power supply system and the safety of train operation, the online monitoring and analysis of transient over-voltage are of great significance. By analyzing and comparing the characteristics of the existing power grid over-voltage online monitoring devices at home and abroad, and due to the difficulty in detecting the power grid voltage on the high-speed train, a new type of over-voltage online monitoring using the broadband transmission characteristics of the equipment is proposed for the high-speed train. The principle of the scheme is to reconstruct the real-time voltage waveform of the primary side of the transformer by convolving the secondary side voltage waveform of the vehicle-mounted voltage transformer through the fast Fourier transform with the transformer-specific transmission parameter model and to correlate the relevant data, such as power, voltage fluctuation, harmonic distortion, etc. Simultaneously, simulation and experiments are carried out to verify the validity and stability of the scheme algorithm. The experimental results show that the system has good response characteristics, high measurement accuracy, and stable and reliable working conditions. The system achieves the expected design goals, and it has been successfully applied to the online monitoring equipment of EMU power quality. While monitoring the over-voltage of the power grid, this system provides data support for the research on the aging and life of the onboard high-voltage electrical equipment.

Comparative analysis of options for constructing an antenna array of onboard high-speed radio link equipment

Comparative analysis of options for constructing an antenna array of onboard high-speed radio link equipment

QoE-Aware Efficient Content Distribution Scheme For Satellite-Terrestrial Networks

The satellite-terrestrial networks (STN) utilize the spacious coverage and low transmission latency of the Low Earth Orbit (LEO) constellation to transfer requested content for subscribers especially in remote areas. With the development of storage and computing capacity of satellite onboard equipment, it is considered promising to leverage in-network caching technology on STN to improve content distribution efficiency. However, traditional caching and distribution schemes are not suitable in STN, considering dynamic satellite propagation links and time-varying topology. More specifically, the unevenness of user distribution heightens difficulties for assurance of user quality of experience. To address these problems, we first propose a density-based network division algorithm. The STN is divided into a series of blocks with different sizes to amortize the data delivery costs. To deploy the caching satellites, we analyze the link connectivity and propose an approximate minimum coverage vertex set algorithm. Then, a novel cache node selection algorithm is designed for optimal subscriber matching. On the basis of time-varying network model, the STN cache content updating mechanism is derived to enable a stable and sustainable quality of user experience. The simulation results demonstrate that the proposed user-oriented STN content distribution scheme can obviously reduce the average propagation delay and network load under different network conditions and has better stability and self-adaptability under continuous time variation.

Algorithms of the Intelligent System for Ensuring Cybersecurity of on-board Equipment Supersonic Passenger Aircraft

This paper discusses the principles of forming a cyber-safe complex of on-board equipment for a supersonic passenger aircraft (SPA). The article discusses two-level protection of the on-board network against unauthorized access. The possibility of using algorithms based on blockchain and block encryption for the future protection of SPA from external and internal threats is being investigated.

АНАЛИЗ ЭФФЕКТИВНОСТИ РАБОТЫ ВЫДЕЛЕННЫХ ПОЛОС ДЛЯ ОБЩЕСТВЕННОГО ТРАНСПОРТА НА ОСНОВЕ GPS-ТРЕКЕРОВ БОРТОВОГО ОБОРУДОВАНИЯ ПОДВИЖНОГО СОСТАВА

The work of dedicated lanes of St. Petersburg is considered. To determine the efficiency of lanes for public transport, an algorithm based on GPS trackers of on-board equipment of rolling stock has been developed. To calculate the indicators of speed and time by coordinates, a formula for spherical distance is proposed, which is used in the theorem of spherical cosines. The results obtained were confirmed by natural studies and simulation modeling. The algorithm can be used both for functioning VP and for those being designed. The implementation of the developed al-gorithm will save the city budget due to low cost and labor costs.

Two-phase heat transfer devices for passive cooling of electric and hybrid aircraft onboard equipment

Two-phase heat transfer devices for passive cooling of electric and hybrid aircraft onboard equipment

Two-phase heat transfer devices for passive cooling of electric and hybrid aircraft onboard equipment

Two-phase heat transfer devices for passive cooling of electric and hybrid aircraft onboard equipment

MATHEMATICAL MODELING OF THE STRENGTH OF PARACHUTELESS AIRDROP SYSTEMS FROM HELICOPTERS

The article is devoted to the simulation of parachuteless airdrop system from helicopters during tests. The issue of testing the equipment strength for parachuteless airdrop is considered in detail. Simulated mathematical modeling of the structural strength characteristics of the parachuteless airdrop system was performed. An assessment of the power strength elements of the removable on-board equipment for parachuteless airdrop design from helicopters is given.

Modern approaches of high-voltage transmission lines monitoring

Transmission lines require timely inspection and monitoring to prevent emergency situations during operation. System emergency situations as blackout are very undesirable, so they need their previous detection and prevention. Accordingly, this can be avoided by detailed monitoring the functioning of all elements of the power system. The directions of remote control for researching the operational state of electric power facilities through the use of special equipment, in particular aerial vehicles, have gained sufficient development. Possibilities of practical means of remote monitoring of power transmission lines are also considered. Due to their relatively inexpensive use and ease of operation, distant controlled aerial vehicles are an effective approach for surveying high-voltage power lines. A number of advantages of using distant controlled aerial vehicles are the extended functionality of monitoring quality provided by modern equipment. Functional analysis of modern on-board equipment indicates the possibility of detecting research objects on a real-time scale, due to the use of telemetry, satellite and combined television and thermal imaging systems, with the possibility of detailed observe. The most perspective is the use of combined heat-television systems, which allow improving the technical characteristics of the surveillance system significantly. This method provides monitoring of heat losses, detection of overheated elements of transmission lines and assessment of the performance of elements. Such technology ensures more safer and timely detection of malfunctions, threats to operation and carrying out work on their elimination. In addition, the fields of application of distant controlled aerial vehicles as surveys for the design of energy systems are increasing.

ENERGY CALCULATION OF SMALL-SIZED UAVs AUTOMATIC OPTOELECTRONIC OBSERVATION SYSTEMS

Great popularity of small unmanned aerial vehicles (UAVs) in remote observation tasks requires further improvement of not only the carrier, but also the on-board equipment. Standard means of surveillance for UAVs are television cameras. Thermal imaging cameras are used in more expensive technical solutions. The efficiency of the functioning of these devices primarily depends on spatial and energy resolution of their input units, which containe optical system and detector. Small-sized UAVs operate at short distances. The peculiarity of useful signal formation by optical-electronic surveillance systems (OESS) of such UAVs is the need to primarily ensure sufficient energy sensitivity.
 The article develops a method for determining the energy resolution of short-range automatic UESs with two information channels - television and thermal imaging. It is justified that for simplified calculations it is advisable to use the functions of the noise-equivalent luminance difference and the noise-equivalent temperature difference of the corresponding channel as quality indicators. Examples of energy resolution calculations of television and thermal imaging channels of the OESS with matrix detectors are given. The influence of focal length and of entrance pupil diameter of the lenses on the energy resolution was studied for observation distances from 0.5 km to 2 km. It is shown that, in OESS with variable magnification, lenses with a larger diameter of the entrance pupil are preferred - they provide more uniform energy sensitivity when changing the focal length. The developed calculation methods can be used for multispectral OESS operating in the visible and infrared spectrum ranges.

Research on text fault recognition for on-board equipment of a C3 train control system based on an integrated XGBoost algorithm

Abstract The robust guarantee of train control on-board equipment is inextricably linked to the safe functioning of a high-speed train. A fault diagnostic model of on-board equipment is built utilizing the integrated learning XGBoost (eXtreme Gradient Boosting) algorithm to help technicians assess the malfunction category of high-speed train control on-board equipment accurately and rapidly. The XGBoost algorithm iterates multiple decision tree models to improve the accuracy of fault diagnosis by lifting the predicted residual and adding regular terms. To begin, the text features were extracted using the improved TF-IDF (Term Frequency–Inverse Document Frequency) approach, and 24 fault feature words were chosen and converted into weight word vectors. Secondly, considering the imbalanced fault categories in the data set, the ADASYN (Adaptive Synthetic sampling) adaptive synthetically oversampling technique was used to synthesize a few category fault samples. Finally, the data samples were split into training and test sets based on the fault text data of CTCS-3 train control on-board equipment recorded by Guangzhou Railway Group maintenance personnel. The XGBoost model was utilized to realize the automatic fault location of the test set after optimized parameter tuning through grid search. Compared with other methods, the evaluation index of the XGBoost model was significantly improved. The diagnostic accuracy reached 95.43%, which verifies the effectiveness of the method in text fault diagnosis.