Rail Track Research Articles

Robust sensors enabling condition-based maintenance of lubricated components in locomotives and wagons

Digitalization in mobility is considered the key to success to increase efficiency, reliability and safety in rail transport, both track and rolling stock. “Big data” analytics are therefore implemented. In the European Joint Undertaking “Shift2Rail”, tremendous efforts are dedicated to condition-based maintenance (CBM). The task of AC2T research GmbH is to enable data collection, processing and evaluation by appropriate sensor systems for online health status monitoring of lubricated components in locomotives and wagons to increase safety and availability while reducing of maintenance costs and unplanned downtime. Special attention is paid to robustness of both sensor and algorithm to meet the high demands for reliability in rail transport. Suitable sensor systems were compiled for three use cases at locomotives and wagons by the field-to-lab approach and validated for use in CBM.

ШЛЯХИ ПІДВИЩЕННЯ ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ ІНТЕНСИФІКАЦІЇ ВИРОБНИЦТВА ПРОДУКЦІЇ РОСЛИННИЦТВА ПОВОЄННОГО ЧАСУ

The purpose of the research is to conduct a detailed scientific and practical substantiation of the ways to increase the economic efficiency of the intensification of the production of plant products in the post-war period. The research used general scientific (generalization, comparison, induction and deduction) and empirical-theoretical methods (analysis, synthesis). The use of system-structural and statistical analysis made it possible to distinguish the main statistical data of crop production. It was established that almost a quarter of the industry was lost in agriculture, and direct losses as a result of the 9-month war reached 6.6 billion US dollars, and indirect losses - 34.5 billion US dollars. It was established that at the end of 2021, there was an increase in production in agriculture (the index of agricultural products increased by 14.4% compared to "minus" 10.1% in 2020) due to significant growth in crop production. It was found that in order to intensify the production of plant products, it is necessary to increase the production of agricultural crops due to the use of more arable land or to increase production on existing arable land by increasing the yield or intensity of crops by improving management methods and genetics. It has been established that the priority tasks in the agricultural sector are to bring the track width and rail cars of Ukraine into compliance with EU standards; increasing the capacity of grain bunkers in Ukraine according to the EU standard; providing Ukrainian farmers with seed, fertilizers, fuel, generators and agricultural machinery; formation of safe working conditions (demining of cultivated areas); maximum sowing of agricultural crops in safe regions of the country; the use of innovative technologies in the production and storage of agricultural crops. The results of the research can be used in the process of studying the scientific field "Agrarian Sciences". The results can be aimed at increasing the economic efficiency of the intensification of the production of crop production in the post-war period.

GIS APPLICATION FOR OPTIMUM ROUTE PLANNING FOR METRO RAIL TRANSPORTATION IN ABUJA

Route planners face a complex task when designing rail networks, considering factors such as land use, slope, soil type, lithology, hydrology, and more. This complexity poses a challenge and can lead to inadequate decision-making processes. To simplify this, Geographic Information Systems (GIS) and Multi-Criteria Decision Analysis (MCDA) are used to help stakeholders make informed decisions. In Abuja, a Metro Rail line alignment was proposed to alleviate congestion and accidents in the Zuba, Madalla, Dei Dei, Gwarimpa, Lifecamp, Jabi and Berger areas. The analysis for the selected rail track identified a minimum GRA value of 0.438 and a maximum of 0.781 with a mean and standard deviation of 0.062 and 0.085. A histogram showed GRA values between 0.60 to 0.80 to be predominant along the selected rail route. This study successfully demonstrates the effective application of GIS and MCA principles in optimizing rail route planning for Metro Rail Transportation in Abuja.

Advancing Wildlife Protection: Mask R-CNN for Rail Track Identification and Unwanted Object Detection

Advancing Wildlife Protection: Mask R-CNN for Rail Track Identification and Unwanted Object Detection

Spectral and cross-spectral densities expressions’ refinement for rail vehicle oscillations

In this paper, we derive analytical expressions describing spectral and mutual spectral densities of random processes by performing analytical Fourier transform of the corresponding correlation functions. On the basis of accepted analytical expressions for correlation functions of differentiable random processes, analytical expressions for spectral density and mutual spectral density components, which is a complex frequency function, are derived. The influence of the accepted analytical expressions on the correlation functions, spectral densities, and mutual spectral density components (real, imaginary, amplitude, and phase) on the parameters is presented. Plots obtained using obtained analytical expressions have showed full convergence with those obtained by direct integration of the analytical expression of the correlation function. The analytical expressions given in this paper may be used for investigating various random processes. In particular, spectral and reciprocal spectral densities can be used for approximation of experimentally received spectral densities, including equivalent geometrical irregularities of a rail track and random fluctuations of a rail vehicle. The parameters of analytical expression obtained by such an approximation can be used for generation of analogous experimental multidimensional random processes in the tasks of mathematical modelling.

A Deep Generative Approach for Rail Foreign Object Detections via Semisupervised Learning

The automated inspection and detection of foreign objects help prevent potential accidents and train derailments. Most existing approaches focus on the detection with prior labels, such as categories and locations of objects, and do not directly address detecting foreign objects of unknown categories, which can appear anytime on the rail track site. In this article, we develop a deep generative approach for detecting foreign objects without predefining the scope of objects. The detection procedure consists of the following three steps: first, the model composed of an autoencoder and a discriminator is developed via adversarial training based on normal rail images only; second, the detection of abnormal rail images is implemented based on the anomaly score obtained via the trained autoencoder; and finally, foreign objects are detected by filtering the subtle dissimilarity in normal areas and highlighting abnormal areas. The effectiveness of the proposed framework for the rail foreign object detection is validated with images collected by a train equipped with visual sensors. Computational results demonstrate that our proposal is capable to achieve an impressive performance on detecting numerous foreign objects. Moreover, two groups of benchmarking methods are employed to verify the superiority of the proposed framework.

ANALYSIS OF ROBOTIC FEEDERS FOR LIVESTOCK COMPLEXES FOR THE CATTLE BREEDING

Production experience shows that the development of agriculture follows the path of automation and robotization of production processes. (Research purpose) The research purpose is conducting a technological analysis of robotic devices for the preparation and/or distribution of feed mixtures at livestock complexes for the cattle breeding. (Materials and methods) Used mathematical statistics tools and software to visualize the results of the study. We analyzed the websites of manufacturers of automatic feeding systems, Russian and foreign electronic libraries of scientific literature eLibrary, Scopus, MDPI and others. (Results and discussion) The classification of the results of technological analysis was given. For the representativeness of the sample, we presented a list of machines, links to sources and analyzed parameters in the form of a table. The obtained information was investigated and statistically processed. The following parameters were determined as the basis of the analysis: type of propulsion; type of power plant or power source; presence/absence of mixing function; the design of the mixing unit; the presence/absence of a self-loading function. (Conclusions) It was revealed that 86 percent of the models in the line of manufactured robotic feeders are mobile, of which 50 percent are wheeled, and 36 percent move along suspended rail tracks. It was found that 9 percent of mobile robots operate from internal combustion engines, 44 percent - from the power grid, 47 percent - from the battery. It was shown that 59 percent of mobile robots perform the function of mixing, 41 percent - only the distribution of ready-made feed mixtures; the most common robot designs with a volume of 2-4 cubic meters. It was noted that one of the key factors determining the design of a robotic feed dispenser is the type of automatic feeding system that it is part of. It was stated that the further direction of the study will be the development of a conceptual model of an automatic feeding system for domestic farms and complexes.

Determination of rail deformations using fiber optic technologies

This paper discusses the application of the fiber-optic technologies in measuring the parameters of the stress-strain state of a seamless track rail. Measuring modules are attached directly to the side surface of the rail and contain fiber-optic sensors with a special structure for changing the refractive index along the length of the base part. The values of deformations are determined during full-scale measurements when analyzing changes in the parameters of the light pulses passing through an optical channel with Bragg gratings. The implemented approaches in measurements and simulation are relevant for the sections of the railway track that are most susceptible to deformations with a large gradient of values, for example, at turnouts, in the places of subgrade heaving, etc.

Traffic Emissions due to Changes in Road Layout in Developing Township Related to Double Track Rail Project Constructions

Traffic emissions in developing townships are less studied compared to major townships and cities. The Electrified Double-Track Project (EDTP) rail line is a linear project traversing from south to north of peninsular Malaysia. Construction of this line has somewhat affected the traffic flow in terms of delay and congestion, affecting traffic-related emissions. A study on the emission fluctuations due to traffic flow changes during the electrified double-track rail line construction was carried out in Parit Buntar, a developing township north of Peninsular Malaysia. Currently, not many primary study reports furnish insights into the effect of the project’s construction phase. Sidra 6.1 were used to estimate the traffic flow delay and level of service (LOS) at signalised intersections from traffic surveys of six intersections. These inputs were also used to estimate the fuel consumption and cost of fuel consumption for all three stages of emission contribution, namely before construction, during construction, and after construction (commissioning phase). The respective fuel consumption (L/hr.) before the construction, during construction, and post-construction were (437, 174, and 198) at J1, (-, 1650, and 264) at J2, (475, 2429, and 2384) at J3, (332, 336, and 261) at J4, and (206, 13996, and 452) at J5. This study found that a proper signal phasing post construction has improved delay time and traffic emission. The findings should be relevant for researchers interested in the emissions within the developing townships, especially in enhancing road layouts for the sustainability of life and well-being in the local and broader contexts.

Development of an on-board system for diagnosing the technical condition of the tread surface of the wheels of wagons

Introduction. The aim of the study is to develop a basic configuration of the on-board system for diagnosing the technical condition of the wheels tread surface of a wagon while the train is running and to model its operation.Materials and methods. The theoretical studies are based on the methods of Lagrange's analytical mechanics, the theory of oscillations and classical electrodynamics. The simulation was carried out for a flat design scheme using numerical methods. The results were processed using the developed algorithm implemented in the programming language of the Mathcad system.Results. This article studies the problem of the negative impact of local wear of the wheel tread surface on the state of the carriage chassis of the car and the rail track, as well as on the safety of train traffic. The authors propose a basic configuration of an on-board system for diagnosing wheel pairs of a wagon with an autonomous power supply with a power of up to 10 W, which simultaneously acts as a sensor. A mathematical model of diagnostic signals for local wheel wear has been constructed, and an algorithm for their detection has been developed based on the results. A criterion for estimating the geometric parameters of wear is formulated and its threshold values for slots of various depths are calculated. Alarms have been identified that suggest a reduction in the speed of the train.Discussion and conclusion. The solution of the stated problem is important both in the operation of existing cars and in the development of new, innovative cars with an axle load of 27–30 tf and speeds of up to 140 km/h. Timely detection of local wear of the tread surface of wagon wheels will increase the level of traffic safety and reduce the cost of repairing cars and rail tracks.

Updating the criteria for assessing the state of the railway track according to the data of track measuring equipment

Introduction. One of the consequences of the introduction of the Instructions for Assessing the Condition of the Rail Track (enacted on February 28, 2020 No. 436/r) was an increase in the number of newly detected deviations from the norm of track maintenance and their reassignment as malfunctions. As a result, the number of kilometres with limited train speeds has increased by up to 3 times, which may lead to significant losses in transportation and an increase in the cost of the immediate track maintenance.Materials and methods. Data from a special thoroughfare of a diagnostic complex along the operating lines of Russian Railways were used to analyse the actual distribution of types and magnitudes of malfunctions, the number and causes of the speed limits. The authors used computer simulations to determine the dynamic indicators of cars in accordance with the algorithm of the deterministic method for calculating the movement of cars along the railway track.Results. The consequences for assessing the state of the track from the standards specified in Instruction 436/r are analysed. The authors present the results of mathematical modelling of the rolling stock interaction with the track, confirming the feasibility of the proposed changes in the standards: increasing the permissible speeds of passenger trains, assessing the gauge widening in curved sections, clarifying the estimates of unbalanced acceleration.Discussion and conclusion. It is proposed to change a number of standards for assessing deviations from the norms of track maintenance in order to reduce the number of speed limits.

INFLUENCE OF WHEEL PROFILE AND HARDNESS ON TRACK STABILITY WITH DIFFERENT STRUCTURE STRUCTURES

For the preparation and during the execution of the work, experimental and theoretical studies were carried out on the influence of the state of the rolling surface profile of the wheelset on the level of interaction forces between the elements of the rail track and rolling stock in operation on the railways of Ukraine. Approaches to modeling the influence of the rolling surface profile of wheelsets on the stability of the wheelset movement and force interaction with the rail track were further developed. Experimental studies of the wear of the rolling surface of wheelsets of rolling stock were carried out, the intensity of their wear depending on the mileage of the locomotive was investigated. Studies of the influence of technical characteristics of hardness in the interaction of rail and wheel and their impact on the service life on the railways of Ukraine are analyzed. After the beginning of operation of wheelsets with increased hardness value, the optimal ratio of hardness of rail and wheel steel was violated. From various sources on the interaction of rails and wheels it is known that the best wear resistance in a friction pair is shown by metals with approximately the same hardness. Based on the data obtained, their analysis was carried out with the development of recommendations for further operation.

Image Classification-Based Defect Detection of Railway Tracks Using Fiber Bragg Grating Ultrasonic Sensors

Structural health monitoring (SHM) is vital to the maintenance of civil infrastructures. For rail transit systems, early defect detection of rail tracks can effectively prevent the occurrence of severe accidents like derailment. Non-destructive testing (NDT) has been implemented in railway online and offline monitoring systems using state-of-the-art sensing technologies. Data-driven methodologies, especially machine learning, have contributed significantly to modern NDT approaches. In this paper, an efficient and robust image classification model is proposed to achieve railway status identification using ultrasonic guided waves (UGWs). Experimental studies are conducted using a hybrid sensing system consisting of a lead–zirconate–titanate (PZT) actuator and fiber Bragg grating (FBG) sensors. Comparative studies have been firstly carried out to evaluate the performance of the UGW signals obtained by FBG sensors and high-resolution acoustic emission (AE) sensors. Three different rail web conditions are considered in this research, where the rail is: (1) intact without any defect; (2) damaged with an artificial crack; and (3) damaged with a bump on the surface made of blu-tack adhesives. The signals acquired by FBG sensors and AE sensors are compared in time and frequency domains. Then the research focuses on damage detection using a convolutional neural network (CNN) with the input of RGB spectrum images of the UGW signals acquired by FBG sensors, which are calculated using Short-time Fourier Transform (STFT). The proposed image classifier achieves high accuracy in predicting each railway condition. The visualization of the classifier indicates the high efficiency of the proposed paradigm, revealing the potential of the method to be applied to mass railway monitoring systems in the future.

An Index for Rail Weld Health Assessment in Urban Metro Using In-Service Train

Rail welds are considered as the weak part of a railway track. Their defects and health can directly affect wheel-rail interaction, track safety, and reliability. Current practices for rail welds health assessment are based on 2D vertical and lateral wear measurement which needs time and track blocking. The development of inertia-based condition monitoring methods such as measuring axle box acceleration (ABA) comes with a crucial question on criteria or index for each rail track component health monitoring. In this study, an index for evaluation of rail weld health is proposed through integrated numerical and field experiment data within a metro line using the ABA technique. The relationship between the speed, wheel structural vibration, and acceleration amplitude is investigated using fast Fourier transformation (FFT) and a nonlinear neural network principal component analysis (PCA) model. An index is introduced to assess weld severity level based on the statistical method. This index is simple and applicable for maintenance practice.

Customized Design of Inductive Sensor for an Early Detection of Cracks in Indian Rail Transport

The objective of this paper is to provide a solution to a serious issue in today’s world of transportation through railways. The practice to examine the flaws which leads to serious effects in rail track is rail inspection. Among the world countries, Indian railways are the fourth-longest, but when it comes to reliability and safety it lags to provide world standard. As a result, if the track is damaged, it leads to severe loss of valuable human lives and property. This derailment in tracks is caused due to cracks in the rails. Therefore, an early crack detection and protection system is required to save the lives. This paper proposes a customized design of an inductive transducer and crack detection system on railroad tracks to avoid the train accidents. Existing method uses the manpower to identify the cracks and this involves human errors. So, the drawbacks in the existing method can be reduced by the automatic system. Customized inductive sensor is designed and developed using ANSYS. A scaled down model of a cart is fabricated and the inductive sensor is assembled at beneath surface of the cart. The track is acting as a part of the magnetic core for the inductive sensor and voltage is induced in the sensor. The sensor voltage is calibrated to distinguish the magnitude of voltage from the normal to crack.

Evaluation of the Aerodynamic Effect of a Smooth Rounded Roof on Crosswind Stability of a Train by Wind Tunnel Tests

The advent of high-speed trains led to new issues and constraints for railway network manufacturers and operators. This is the case of crosswind effect, that occurs when train is running in strong wind conditions. The combination of train speed and wind speed generates a relative flow that affects the train stability. Wind tunnel tests on still railway vehicles (relative wind-train velocity in coincidence with absolute wind velocity) are mandatory according to Technical Specification for Interoperability (TSI) to ensure high-speed train safety. However, issues related to the correct evaluation of the full-scale aerodynamic behaviour of the trains can arise. In the present work, aerodynamic force and pressure coefficients measured in wind tunnel tests on a scaled model of ETR1000 high-speed train on single track ballast and rails are presented. The tests were performed in the GVPM wind tunnel of Politecnico di Milano. Results show that different flow behaviours can occur at high yaw angles when the train behaves like a bluff body depending on wind speed used during the test.

Экспериментальные исследования колебаний трамвая «Витязь-М»

Objective: Based on experimental studies of vibrations of Vityaz-M tram car occurring at speeds of 50 km/h or more on track straight sections with P65 rails on reinforced-concrete sleepers, to evaluate the effect of transversal vibrations on traffic safety and passenger comfort. To show the inconsistency of existing regulatory documentation on the structure and maintenance of tram tracks and tram chassis with the development prospects. Methods: Experimental measurements of vibration accelerations of tram body and tram chassis, having different mileage, when moving along track experimental section. Measurement and analysis of geometric parameters of rail track experimental section and of trams. Results: Measurements of vibration accelerations occurring during tram motion with 20 to 50 km/h speeds were performed as well as geometric parameter analysis for rail track experimental section and rolling stock wheels’ profiles, participated in the tests, was pursued. During the races, vibration accelerations that occur during movement were measured in three directions — longitudinal, transversal and vertical. The appearance of transversal vibrations of tram body affecting passenger discomfort and traffic safety has been confirmed. The root mean-square values of the amplitudes of vibration accelerations towards three directions in acceleration gravity (g) fractions have been obtained in two variants — at trolley motion between joints and at joints. Vibration acceleration frequency analysis has confirmed a sharp increase in the amplitude of transversal vibrations at frequencies in the region of 1–2 Hz at a speed of 50 km/h for a tram with worn wheels. The compliance of rail track experimental section geometry with the accepted standards as well as the compliance of rolling stock wheels dimensions with constructive documentation are noted. Practical significance: The need for further comprehensive study of the interaction of track and rolling stock while high-speed tram introduction with the purpose to improve existing standards on the structure and maintenance of tram tracks and tram chassis.

An Online Rail Track Fastener Classification System Based on YOLO Models

In order to save manpower on rail track inspection, computer vision-based methodologies are developed. We propose utilizing the YOLOv4-Tiny neural network to identify track defects in real time. There are ten defects covering fasteners, rail surfaces, and sleepers from the upward and six defects about the rail waist from the sideward. The proposed real-time inspection system includes a high-performance notebook, two sports cameras, and three parallel processes. The hardware is mounted on a flat cart running at 30 km/h. The inspection results about the abnormal track components could be queried by defective type, time, and the rail hectometer stake. In the experiments, data augmentation by a Cycle Generative Adversarial Network (GAN) is used to increase the dataset. The number of images is 3800 on the upward and 967 on the sideward. Five object detection neural network models-YOLOv4, YOLOv4-Tiny, YOLOX-Tiny, SSD512, and SSD300-were tested. The YOLOv4-Tiny model with 150 FPS is selected as the recognition kernel, as it achieved 91.7%, 92%, and 91% for the mAP, precision, and recall of the defective track components from the upward, respectively. The mAP, precision, and recall of the defective track components from the sideward are 99.16%, 96%, and 94%, respectively.

The History of Development of Inland Transport Infrastructure: Technology and Economic Aspects. Part 2

The second part of the article (the first of which was published in the last issue of the journal) analyses the history of emergence of the rail track, as well as evolution of the railway-track substructure, including a review of the materials used for this.A separate section is devoted to evolution of railways in Russia.Brief conclusions are made regarding the importance of the historical and economic aspects of development of inland transport infrastructure.The importance of considering this issue is quite high when conducting comprehensive research intended to get economic assessment and forecast the strategic development of transport infrastructure.

Effect of clay fouling on track drainage capacity of railway Ballast: Experimental and numerical study

Ballast fouling is a key contributor to the instability of ballasted railway tracks due to its detrimental influence on the permeability of the ballast layer. Predicting the track drainage condition in a ballasted track segment frequently affected by fouling is vital for planning track maintenance activities. However, only limited studies have been conducted to assess the hydraulic conductivity and track drainage capacity of fouled railway ballast. Hence, full-scale permeability tests were performed in this study using an in-house custom-built large-scale permeability apparatus at the laboratory to attain hydraulic conductivities for 5 different fouling levels of ballast fouled with sandy lean clay material. Based on the experimental results, a relationship between the Void Contamination Index (VCI) and hydraulic conductivity was obtained. The results elucidated that the fouling material reduced the hydraulic conductivity of ballast by more than 90% when VCI was 25% or higher. In addition, using the hydraulic conductivity values obtained from experimental results, a detailed 2D numerical seepage analysis of a rail track was carried out to represent the track drainage capacity at various fouling levels. Based on the results, the significance of maintaining a clean top ballast layer and shoulder ballast was highlighted and a criterion for estimating the drainage capacity of a clay-fouled railway track was proposed to initiate track maintenance operations.