Railway Traffic Control Systems Research Articles

Model of Electric Locomotive Simulator Cabin Excitations

Striving to increase the speed of rail vehicles and thus improve the comfort of traveling passengers at the same time, undertakes activities in the sphere of ensuring an appropriate level of safety of rail, passenger, and freight transport. One of the elements of activities in this area is the training of train drivers. Until recently, this training consisted of a theoretical and practical part on the vehicle, alongside an experienced train driver. Considering the increasing level of automation of railway traffic control systems and locomotive equipment, as well as training costs and requirements related to the introduction of TSI, it is becoming an increasingly common requirement to conduct practical training on railway vehicle traffic simulators, while the conditions in the simulator cabin and the trainee’s feelings should correspond to the actual driving conditions. A locomotive driving simulator is a system consisting of a cabin of a suitable type of locomotive or EMU, mapped in 1:1 scale, coupled with a motion excitation system and computer programs connected together forming the software of the cab visualization and dynamics system. The basic program simulating the dynamics and kinematics of the cabin’s motion is a program containing a motion dynamics model that generates signals forcing the movement of the exciters on which the cabin’s platform is mounted. The correct operation of the simulation model depends on the created mathematical model, which can be built in several ways. This article presents the issue of building a mathematical model describing the dynamics of the rail vehicle motion, which can then be used in the simulation model of the simulator cabin motion. Two ways of proceeding in the process of approaching the construction of a mathematical model of rail vehicle motion dynamics will be presented, with the possibility of later use in creating a simulation model of the motion of the locomotive simulator cabin. One of the possible routes was used in the past in the construction of the EP09 locomotive simulator.

Analysis of the possibility of using the satellite navigation system in the railway traffic control systems

The analysis of the possibility of using satellite navigation for rail vehicle positioning, which is the subject of many studies and projects, is aimed at assessing the uncertainty and accuracy of train positioning using satellite navigation systems, along with defining its impact on the capacity and safety of the rail infrastructure. Existing studies in this area prevent a clear assessment of the feasibility of implementing a satellite navigation system for rail vehicle positioning in rail traffic control systems. Therefore, it is necessary to analyze the possibility of using satellite navigation for rail vehicle positioning in terms of research problems arising from the limitations of satellite positioning system functionality, which include parameters related to accuracy, reliability, and speed of information transfer between the vehicle and the rail traffic control system. The implementation of the research work should be focused on developing a research model, subject to validation for the parameters and conditions of movement of rail vehicles in the defined area of railroad infrastructure, adopted within the framework of the work carried out. The research and the model form the basis for developing the knowledge of implementing satellite navigation in practical solutions on the railroad network.

Electromagnetic Impact of Overhead High-Voltage Lines during Power Transmission on Buried Signaling Cables of the Traffic Control Systems in Modernized Railway Lines

The railway transport system is a key factor supporting industrialization in all aspects of human activity. However, in order not to lose its importance, it must meet the challenge of modern civilization. The safety, reliability, and efficiency of railway transport, to a large degree, depend on using highly integrated electronics, which are very sensitive to various disturbances generated in the electric traction system and train or coming from the environment. One of the sources of electromagnetic disturbances are high-voltage (HV) power lines running close to the railway infrastructure. The purpose was to assess the electromagnetic impact of overhead HV transmission lines on buried signaling cables of the railway traffic control system crossbreeding with them. The levels of voltage induced in the cable under steady state and the earth fault in the HV line at various soil resistivity were estimated. A software tool based on a hybrid numerical method that combines circuit theory and electromagnetic field theory was used for computations. It was found that very high voltages may be induced in the signaling cables during earth faults in the HV lines, which may lead to serious interference or damage to the equipment. The results provide useful knowledge for implementing modern railway traffic control systems and protection measures.

Safe device solutions in railway traffic control systems

The paper deals with the problems of safe solutions of railway traffic control systems, using the example of modern solutions of protection systems applied at railway level crossings. The need for reliable, modern and safe railway traffic control devices has forced manufacturers in the railway industry to use high quality microprocessors in their structures. Devices used to safety traffic at intersections of railroads and roadways in one level shall be absolutely operational and reliable. Such solutions are the modern systems of automatic level crossing signaling made in computer technology. They use structural redundancy, programmable logic controllers, and have extensive self-diagnostic and technical diagnostic mechanisms. The paper presents selected analyses of railway traffic safety on the example of the automatic level crossing of system BUES 2000 type by Scheidt & Bachmann.

Innovative railway traffic control systems on the PKP Network, part I

W artykule zaprezentowano wybrane nowoczesne systemy sterowania ruchem kolejowym stosowane na sieci PKP. Zaprezentowano także, z czym wiąże się Techniczna Specyfikacja Interoperacyjności (TSI) oraz w jakim zakresie dotyczy zagadnienia sterowania ruchem kolejowym. Omówiono podstawowe różnice w zakresie poziomów systemu ERTMS/ETCS oraz zagadnienia dotyczące bezpieczeństwa. Zastosowanie nowoczesnych urządzeń sterowania ruchem kolejowym jest podsumowaniem rozwoju kolei pod kątem technicznym i organizacyjnym, mającym na celu poprawę poziomu bezpieczeństwa na sieci kolejowej oraz zapewnienie interoperacyjności systemów kolejowych.

Temporal Verification of Relay-Based Railway Traffic Control Systems Using the Integrated Model of Distributed Systems

Relay-based traffic control systems are still used in railway control systems. Their correctness is most often verified by manual analysis, which does not guarantee correctness in all conditions. Passenger safety, control reliability, and failure-free operation of all components require formal proof of the control system’s correctness. Formal evidence allows certification of control systems, ensuring that safety will be maintained in correct conditions and the in event of failure. The operational safety of systems in the event of component failure cannot be manually checked practically in the event of various types of damage to one component, pairs of components, etc. In the article, we describe the methodology of automated system verification using the IMDS (integrated model of distributed systems) temporal formalism and the Dedan tool. The novelty of the presented verification methodology lays in graphical design of the circuit elements, automated verification liberating the designer from using temporal logic, checking partial properties related to fragments of the circuit, and fair verification preventing the discovering of false deadlocks. The article presents the verification of an exemplary relay traffic control system in the correct case, in the case of damage to elements, and the case of an incorrect sequence of signals from the environment. The verification results are shown in the form of sequence diagrams leading to the correct/incorrect final state.

Human Factor Analysis of the Railway Traffic Operators

The human factor is an essential aspect of the operability and safety of many technical systems. This paper focuses on the analysis of human errors in the railway domain. The subject of human reliability analysis is the behavior of operators of station-signaling systems responsible for rail traffic management. We use a technique for human-error rate prediction as the 1st generation human reliability analysis to deal with task analyses, error identification and representation, and the quantification of human error probabilities. The paper contributes to the comparison of three technologically different railway traffic control systems, having different degrees of automation—from the manually operated (electro-mechanical), through semi-automated (relay-based) to almost fully automated (computer-based) station-signaling systems. We observe the frequency of individual operations performed in time intervals and calculate human error probability and human success probability values for each operation. Thus, we can analyze human reliability and compare the workload of operators working with control systems of different degrees of automation.

Propaedeutic of the methodology of improving electromagnetic compatibility of railway traffic control systems in relation to the implementation of the EMC4CCS - BRIK project

The purpose of this article is to introduce to the methodology of increasing electromagnetic compatibility in distributed system, on the example of the implementation of works in the field: "Research and improvement of electromagnetic compatibility of railway traffic control devices and rolling stock", which are the subject of the BRIK project. The methodology is defined here as a set of rules for conducting research in order to achieve an intended goal. The article proposes a procedure to improve the EMC condition of distributed systems. For monitoring the quality of the system operation in terms of electromagnetic compatibility, the implementation of the OEE indicator was suggested.

Railroad Turnout Wear Diagnostics.

The article presents a few issues related to the technical condition of a railway turnout, an important element of the railway network where about 90% of railway accidents occur. In the first part of the article, the results of railway turnout wear are presented. A comparison of normal forces (in wheel–rail contact) in vehicle traffic on straight track without a turnout and normal forces occurring when a rail vehicle passes a turnout is presented. Then, turnout wear processes for selected speeds are presented. In the next part of the paper, the possibilities of using a vision system are presented, which, in combination with tools for image processing analysis, makes it possible to detect wear and distances between the key elements of a railway turnout. The main idea of the proposed online diagnostic system solution is to use the analysis of received images (photos) with the help of a vision system. The basic problem to be solved in the proposed system was to develop algorithms responsible for generating wear areas from high-resolution images. The algorithms created within the work were implemented and tested in the MATLAB software environment. The presented method is an original procedure for diagnosing turnout elements for each time instant. The proposed system is compatible with railway traffic control systems.

Optimization of Safety System Structures in Railway Transport

One of the basic strategies for reacting to unacceptable risk is introducing new elements to the analyzed domain. These elements and the relations between them can be treated as a safety system. Although expanding the safety system usually reduces the risk of specific hazards, it often leads to new problems resulting from its excessive development: the system becomes costly and difficult to understand. One of the methods of avoiding the negative issues is to apply an approach described in this paper, which is based on an optimization method making use of the results of risk analysis. The article contains a detailed mathematical description of an optimal solution search algorithm, enabling the selection of a configuration of safety system components that will be the most appropriate in terms of the degree of risk reduction and the related costs. The theoretical part was supplemented with a working example concerning railway traffic control systems. Using the proposed method, it is possible to obtain an optimal structure of a safety system, ensuring at least a tolerated level of risk, adequate to the identified hazards.

Selected Issues of Safe Operation of the Railway Traffic Control System in the Event of Exposition to Damage Caused by Lightning Discharges

Lightning discharge becomes a serious source of interference and damage for electronic and electrical power systems. Safe and reliable operation of railway traffic control systems requires proper protection against the effects of lightning. However, the current standards on lightning protection, PN-EN/EN/IEC 62305, do not cover railway objects. Moreover, there are no other standards or recommendations dedicated to the railway. The paper is an attempt to apply the procedure of lightning risk management according to PN-EN 62305-2 to select the proper protection measures in railway objects. A case study for the signal box with installed relaying and digital stations of the railway traffic control system is analyzed. The analysis comprises calculations based on the current standard PN-EN 62305-2:2012 but including the issues specific to railway traffic control. The risks of lightning losses have been calculated for two cases: without lightning protection measures and with protection measures proposed to decrease the risks below the tolerable values. The results show that a practically effective solution to reduce the risks is applying surge protective devices with proper characteristics. Another way is replacing unshielded incoming lines with shielded ones of given shield bonding way, and supplementing it with surge protective devices when necessary.

Interface and connection model in the railway traffic control system

The article presents a model of connection of ETCS application and classical base layer equipment. The model distinguishes three layers: physical, logic and data, which require different modelling techniques and at the same time must be consistent. The model will form the basis for the digital mapping in the Digital Twin of the ETCS application. Layer division is a natural way to represent the structure of a device and its operating rules. It allows a detailed and structured representation of the interfaces of a connection and then an analysis of the connection both with respect to the layer of interest and from the point of view of the interaction between features in the different layers. The S-interface of the LEU encoder of the ETCS is described, taking into account different solutions encountered in practice. The conditions of the connection between the LEU encoder and the environment form a description of one of the two boundaries between the ETCS application, i.e. the implemented ERTMS/ETCS on a specific area of the railway network, and the environment. A general connection model and definitions of a connection and an interface are presented. As an example, the electrical connection with signals transmitted through galvanic connections has been assumed to be typical for LEU encoder and track-side signalling control circuits found in base layer equipment. The physical layer is described in terms of physical parameters and their values. The parameters are divided into electrical (current, voltage and frequency) and mechanical ones (number of leads, conductor thickness, etc.). The values of the electrical parameters are expressed in terms of a uncountable set with defined limits. The logic layer was described in a vector-matrix form. Logic signals are assigned to electrical signals with specific physical parameters. The data layer contains information about the assignment of specific telegrams to specific electrical signals.

COMMAND – CONTROL AND SIGNALING SYSTEM DOCUMENTATION AND ITS SAFETY

Purpose. The publication presents the importance and influence of railway traffic control system documentation on its safety. Furthermore, it presents certain selected issues of formal and semi-formal descriptions. Methodology. Development of correct and complete descriptions of the informal, semi-formal and formal becomes important in terms of safety requirements. Background documentation and forms of command-control and signaling system description are the base documents of safety proof. It seems necessary to implement the analysis of the design, manufacture process and operation of safety-related equipment into the work of the Polish railways. Firstly it is applied to traffic control devices. Findings. This publication also shows the importance of risk analysis, which is essential when deciding on the implementation of signaling systems to operate, which are required both in the regulations and making rational decisions about the implementation of the systems. Originality. The presented a problem changes the approach to certain data and makes us aware of their validity. Practical value. The presented problems can help understand certain legal requirements.

Issues of Railway Traffic Control Devices Availability in the Exploitation Process

Abstract This article focuses exclusively on the issues of railway traffic control devices availability in traffic management. One of the factors affecting this availability are tests conducted during maintenance or repair works. A review of the literature in the field of test determination methods was conducted. Next, the railway traffic control system was described and the elements influencing availability were defined. Assumptions and an algorithm of the procedure were presented and the method of determining the tests was proposed.

Risks in Investment Processes Covering Railway Traffic Control Systems

Risks in Investment Processes Covering Railway Traffic Control Systems

Modelling of exploitation process of the railway traffic control device

The basic purpose of railway traffic control devices is to ensure a high level of safety of moving trains on the railway network. The railway traffic control devices often work in difficult environmental conditions and are exposed to external interference. These circumstances require continuous analysis of the state of the railway traffic control system. With time, the system's technical condition deteriorates. When its technical condition is not satisfactory it is necessary to operate it and renew its state of use. The rational implementation of exploitation tasks of the railway traffic control system allows the introduction of mathematical modeling methods into exploitation tests. Using the mathematical model of the exploitation process of the railway traffic control system, it is possible to forecast e.g. reliability indicators of its individual objects. Knowledge of exploitation parameters should be used in making decisions in the process of managing the exploitation of the railway traffic control devices.

Failures simulator of railway traffic control devices

Railway traffic control systems may have different working conditions. It results from their destruction process, which is related to the age of the devices, intensity of their operation or technical service quality. Operating tests are the source of valuable knowledge that allows not only to perfect the construction of railway traffic control devices, but also to control the operating process. In order to do that IT tools are developed, supporting the diagnostic process. What can be helpful in testing these tools can be, proposed by the authors of the article, a failures simulator dedicated to railway traffic control devices.

The Maintenance Scheduling Issues of Railway Traffic Control Systems with Respect to Reliability

Abstract Railway traffic control is based on specialized devices that are designed to exclude collision runs that may lead to loss of safety. A research issue arises in the context of determining effective maintenance intervals and the manner of conducting a technical service policy for existing devices. The aim of the article is to determine the structure of reliability research of selected railway traffic control devices in the aspect of device structure, the current strategy and the state of knowledge on service strategies. The article describes railway traffic control devices to discuss the issue of scheduling technical maintenance of this type of system.

Functional analysis of railway traffic control system using an expert system

The major functionality of railway traffic control system is to ensure efficient and safe railway traffic. Contemporary technique, electronics and informatics in particular, allows for automation of more and more tasks in transportation processes. Irrespective of the manufacturing technology, railway traffic control systems have to meet specific safety requirements. Because of this, these systems belong to group of safety-critical systems, also called safety-related systems. Due to these requirements, development, building and verification processes of railway traffic control systems always end with the assessment of correctness of each process. It should be pointed out that these processes are compound and require high skills level for persons involved in it. Because of this, an environment for an expert system (ExSys Corvid) can be used to automation of these processes. Authors used ExSys Corvid environment to build the expert system for verification and validation of Level Crossing Protection System (LCPS). Research conducted by authors confirmed high usefulness of this technology and showed the need for the usage of it in other railway traffic control systems.

Diagnostics of railway control devices

Railway traffic control is performed by the man with the use of specific technical means. Technical development and wide functionality of railway traffic control systems contribute to the fact that one deals with many types of devices, created with the help of various technologies. That is why the maintenance of the devices and systems presents a big challenge for railway infrastructure administrators, and it needs to be supported by technical diagnostics. The need for diagnostics of railway traffic control devices results from their destruction process which is related to their lifespan, use intensity, technical service quality or operation quality level. Gathered in the diagnostics process information concerning changes of the technical condition of the devices allow effective restoring to their original state thanks to regeneration. That is why academic research is being carried out and actions connected to implementing new diagnostic methods in the railway traffic control area are taken. The article presents chosen railway traffic control devices diagnostic systems.