Railway Control Systems Research Articles

Verification of Railway Control Systems Using Model Checking and CTL, Explained Through a Case Study

Systematic faults can often occur during the development of a system. The later such faults are discovered, the more expensive it can be to correct them. In systems engineering practice, there are many methods and tools to reduce the likelihood of systematic faults. In this paper, we present the application of a formal model–based verification technique – called model checking – to assist railway engineers in designing and verifying the safety-related functionality of railway control systems. The proposed process is part of a specification-verification environment that facilitates the construction of correct, complete, consistent, and verifiable functional specifications during development. The results and experience in model checking are illustrated by a case study of a vehicle detection point, a common component in this domain. The model checking of the case study has been performed in the widely used UPPAAL modeling and simulation framework, which can also verify formal properties and generate a counterexample in case of a property violation. By analyzing the counterexample, the designer can gain insights into the system's behavior and identify potential design flaws or failures. Model checking can be used to achieve a higher quality functional specification that is typically more complete and/or contains fewer faults compared to the traditional development approach.

Continuity of GNSS as a critical attribute for safety applications in land transport

The Global Navigation Satellite System (GNSS) is widely used for air traffic management—more than 150,000 aircraft and 5000 airports worldwide are equipped with SBAS (Satellite-based augmentation system) technology, which contributes to safer and more efficient air operations. The next challenge is to extend GNSS positioning to maritime, autonomous cars and railway control systems preserving their safety requirements. The main parameter is the integrity of the GNSS positioning, although the time for which the integrity is guaranteed, defined by continuity, the most demanding requirement for aviation applications, has not been sufficiently investigated for land transportation. The aim of this paper is to close this gap by clarifying: (1) where the requirement for GNSS continuity comes from, (2) why GNSS continuity is needed in land transport, and (3) how GNSS-based applications can be made more reliable when needed. Using a comparative analysis, the continuity requirements in aviation, rail, maritime, and road transport have been investigated showing their importance for railways and automotive control, paving the way to eventually update the current EN 50126 (RAMS) and ISO/TR 4804 standards respectively for railways and automated cars. One of the main findings, through Markov modeling, is the improvement of the Mean Time to System Failure (MTTFsys) that for the railway safety-of-life applications can be significantly increased from about 521 h up to 5 × 105 h. These results can contribute to accelerating the adoption of GNSS positioning for automated land transportation, by exploiting the extensive experience brought by the aviation sector where GNSS was introduced 20 years ago.

A holistic solution to virtual coupling based urban rail train control system

Virtual coupling (VC) is an emerging concept that is gaining popularity in railway control systems. It has the potential to significantly enhance railway capacity and flexibility, and has attracted considerable research attention. This study explores several key aspects of VC research in the context of urban rail transit systems, including system structure, train platoon control method, scenario definition, and train scheduling. The paper presents three main contributions: Firstly, it proposes a potential system structure for VC and discusses infrastructure occupancy procedures within typical operational scenarios. Secondly, a VC platoon controller based on the adaptive back-stepping method is designed to realize the function of the operation layer. Thirdly, combining operational scenario definition and control methods, we propose a VC train scheduling method based on mixed integer linear programming (MILP). A case study demonstrated that the proposed solution could effectively achieve the primary functions of VC.

Integral railway interlocking system and its assessment according to European standards

This paper analyses the component of the Integrated Interlocking System which forms the central logical and functional unit implementing all logical and computational functions necessary for railway traffic control in the Railway 4.0 concept. The main principle is that this approach centralizes the technology of station interlocking system, track line interlocking systems, level crossing interlocking systems and the functions of train interlocking system – the line part of ETCS L2/3 radio block control panel (RBC). The operation control is centralised to the controlling dispatcher centres.The paper discusses the concept of integrated interlocking system including safety issues addressed from the perspective of the requirements of CENELEC standards EN 50126, EN 50128 and EN 50129. These requirements are addressed from the perspective of the authors of the paper, who also work as independent assessors of the safety of railway control and command systems.

Development of an Artificial Intelligence based Railway Crack Detection and Monitoring System using Internet of Things

This study suggests the concept of crack locating robot vehicle in the railway rails. India railways participates an important posture in asset with the necessary transportation to preserve needs of a rapidly emergent financial system. India now has the world's fourth-largest railway network. Therefore, travelling by train is risky. It does not work with the existing railway control system in India. Thus, robust, well-organized, and reliable new technology is required for both fracture detection in railway track and identification of objector items. This study proposes and clarifies a robust monitoring system to meet the limitations of the current rail surveillance system for detecting fractures of the railway tracks. Therefore, robust, well-organized, and reliable new technology is required for both fracture detection in railway track and the identification of objects or items. This study proposes and clarifies a robust monitoring system to meet the limitations of the current rail surveillance system for detecting fractures of the railway tracks. The goal of this study is to build and create an IoT-enabled robot that uses artificial intelligence (AI) to report to a railway controller any information it gathers concerning broken or cracked track. To solve this issue, we will be sending all data over wireless communication based devices and developing a corresponding application..

A Microservices-Based Approach to Designing an Intelligent Railway Control System Architecture

The symmetry between customer expectations and operator goals, on one hand, and the digital transition of the railways, on the other hand, is one of the main factors affecting green transport sustainability. The European Train Control System (ETCS) was created to improve interoperability between different railway signaling systems and increase safety and security. While there are a lot of ETCS Level 2 deployments all over the world, the specifications of ETCS Level 3 are under development. ETCS Level 3 is expected to have a significant impact on automatic train operation, protection, and supervision. In this paper, we present an innovative control system architecture that allows the incorporation of artificial intelligence (AI)/machine learning (ML) applications. The architecture features control function virtualization and programmability. The concept of an intelligent railway controller (IRC) is introduced as being a piece of cloud software responsible for the control and optimization of railway operations. A microservices-based approach to designing the IRC’s functionality is presented. The approach was formally verified, and some of its performance metrics were identified.

A real-time vital control module to increase capabilities of railway control systems in highly automated train operations

Recent advances in technology and railway have led to the introduction of systems and infrastructures capable of driving trains automatically. The Automatic Train Operation (ATO) system has been optimized for active human supervision. The next challenge is to realize ATO systems capable of achieving unsupervised operations on the mainlines. However, at this aim, additional safety functionalities should be provided. In this paper, we propose a pioneer hardware/software Vital Control Module (VCM) architecture capable of expanding the control capabilities of the existing train control system. The VCM includes a Printed Circuit Board (PCB), to be integrated into the cabin equipment, managed by a reliable and safe hard Real-Time Operating System (RTOS). Both hardware and software are developed to be compliant with related safety standards. The VCM integrates an application logic that acts as an on-board equipment control core, assessing the overall operativity in real-time, and promptly issuing emergency brakes if hazardous situations occur. The application logic has been developed with a model-based approach via Simulink/Stateflow tool and implemented as a C-script on the Xilinx Ultrascale + core housed on the PCB. We have used two testbeds to evaluate the VCM performance. Experimental results showed that the Worst-Case Response Time (WCRT) by the application logic is 13.6 times smaller than the most limiting specification-related deadline. The achieved earliness (− 1.8 ms out of 2 ms of deadline) allows for the easy expansion of VCM’s train protection capabilities in the future. Results from the second testbed showed that the VCM can intervene to mitigate hazardous situations ~ 2 times faster than the current automatic train protection systems according to the related standard.

Orchestrator for ensuring interdependency between safety and cybersecurity in railway control systems

ABSTRACT Nowadays, more and more cyber-attacks are documented in transportation systems and this impacts human and environment. Thus, it is important to consider the integration of safety and cybersecurity in both industry and academia. This brings many advantages such as virtualization technologies, but it also creates new vulnerabilities. However, a safety orchestrator that is able to address a variety of safety anomalies that come from safety-related properties and to avoid conflicts with the functionalities of a cybersecurity orchestrator is not found in the literature. To reply to this need, in this paper we propose a new safety architecture for the railway systems. The core of this architecture is STELAC, the first safety orchestrator. This orchestrator covers reliability, availability, maintainability, and integrity-related anomalies as they are the properties which interact and influence safety according to RAMS. This orchestrator is also able to prevent functionality violations between safety and cybersecurity, in order to handle their interdependency. According to the results of the implementation, it is shown that STELAC ensures safety affected by the rest of the aforementioned properties and has little impact on decision-making time, which makes it an effective methodology for using the NFV architecture in railway systems safely and securely.

Development and research of a model of a microprocessor device of a set-up control unit for paired points

The use of electromagnetic relays in railway control systems is very problematic. The solution to this problem is based on process modelling and the use of microelectronic devices. The functional scheme for different modes of operation of twin switches control unit has been developed and investigated. Algorithms and functional scheme of microelectronic unit are given.

WITHDRAWN: Security of Railway Control Systems: A Survey, Research Issues and Challenges

With the rapid development of railway transporta- tion, higher requirements for capacity are increasing and amount of communication, computer and control technologies are applied in train control systems which is the popular method for train control. The application of 3 C brings the enhancement of railway transportation performance. However, the number of internal and external cyber security threats is rising, which could lead to some railway accidents. On the other hand, safety is the core of the design process for railway but security is rarely considered due to the closure of traditional railway systems. As cyber security is threatening the normal operation of industrial control systems and the critical infrastructure, security issues of train control systems should be paid more attention as railway transportation play an important role for society and economy. However, due to the safety-critical characteristics, safety assessment and analysis works have been performed for a long time, but cyber security related works are rarely considered. In the paper, we demonstrate the security situation of train control systems based on the inherent features and the experience of other industrial control systems, where the technical defects and potential threats are summarized. According to the practical engineering experience, the current security protection strategies are illustrated, which shows the popular security protection methods are limited and cannot realize the defense-in-depth. Finally, some research challenges of security issues of train control systems are identified.

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.

Formal Modeling and Verification of the Functionality of Electronic Urban Railway Control Systems Through a Case Study

This paper presents a formal model-based methodology to support railway engineers in the design of safe electronic urban railway control systems. The purpose of our research is to overcome the deficiencies of existing traditional design methodologies, namely the incompleteness and the potential presence of contradictions in the system specification resulting from non-formal development techniques. We illustrate the application of the methodology via a case study of a tram-road level crossing protection system. It was chosen partly because it has a simple architecture and a small number of elements, thus it fits the scope limitations of this article. At the same time, it is suitable for presenting all essential features of our methodology. The proposed solution provides a specification/verification environment that facilitates the construction of correct, complete, consistent, and verifiable functional specifications during the development, while hiding all the formal method-related details from the railway engineers writing the specifications. Using this formal model-based methodology, a high-quality functional specification can be achieved, which is guaranteed to be more exhaustive and will contain fewer errors than traditional development.

Design and Implementation of Intelligent Railway System

Digital model railway control systems provide a new way to regulate a layout while reducing wiring and increasing operational flexibility. A variety of control systems are available for operating locomotives on model railroads. Analog systems, in which a train's speed and direction are controlled by changing the voltage on the track, are still in use, though computer-based control systems have recently taken their place. Our technology is a cutting-edge computer-assisted railway line inspection technique. It will take the tedium out of manually inspecting train tracks. The proposed system will modernize the inspection process with four modules. Two trains on the same track will be detected by the system, preventing a collision. If this is included, it will automatically activate the level crossing system. Apart from that, it will detect major obstructions on the rail track, as well as track damage and missing rails.

Calculation algorithm and method for optimizing electricity consumption for the railway traction system

Abstract This article presents a calculation algorithm for establishing the electricity demand consumed by the railway electric traction system on a railway section, as well as methods for lowering power consumption and cost. In order to conceive the calculation algorithm, the following variables are taken into account: the number of trains in circulation on the section, the slope of the section, the train speed and the speed restrictions. For factors that substantially increase electricity consumption, but can be controlled, optimal values are computed using specific equations in the MATLAB program. The optimal values are implemented using the train’s timetable or a railway control system (SCADA). A decrease in power consumption of 5% can be expected with this method.

Runtime verification of train control systems with parameterized modal live sequence charts

With the growing complexity of railway control systems, it is required to preform runtime safety checks of system executions that go beyond conventional runtime monitoring of pre-programmed safety conditions. Runtime verification is a lightweight and rigorous formal method that dynamically analyses execution traces against some formal specifications. A challenge in applying this method in railway systems is defining a suitable monitoring specification language, i.e., a language that is expressive, of reasonable complexity, and easy to understand. In this paper, we propose parameterized modal live sequence charts (PMLSCs) by introducing the alphabet of the specification into charts to distinguish between silent events and unexpected events. We further investigate the expressiveness and complexity theories of the language. In particular, we prove that PMLSCs are closed under negation and the complexity of a subclass of PMLSCs is linear, which allows the language to be used to monitor a system online. Finally, we use PMLSCs to monitor an RBC system in the Chinese high-speed railway and evaluate the performance. The experimental results show that the PMLSC has high monitoring efficiency, and can reduce false alarm rate by introducing alphabets of charts.

Cyber security in industrial control system

For any system to secure them industrial control system plays an important role in it. It helps to design the isolated procure system, specialized communication mechanisms is used to help for the setup. And with the help of this setup the flexibility, safety, threats, and vulnerabilities are the most important things to make. To secure them from risk assessment and other protection measurement need to specify with good instruments and security. The paper describes technical aspects on Denial of Service (Dos) attack. We also identify how smart grid communication networks works in security technical implementation guides of the different countries as a defense information systems agency. A brief chronicle of cyber storm on ICS; common challenges, some mitigation of those challenge, all levels of the multi-layered ICS architecture. This paper demonstrates railway control systems (RCS) compliance estimation of immovable control system design, operational scenarios that can be used for mitigation measures and security assessment.

Оцінка програмного забезпечення систем залізничного транспорту станційного рівня на відповідність вимогам українських стандартів

The purpose of this article is to find effective methods for assessing and proving the functional safety of software at the station level railway control systems. Adaptation of experience and development of a common approach to the software verification process. Method. To achieve this purpose the analysis of current regulatory documents was conducted. An adaptation of the existing experience in performing the conformity assessment of information and control systems important for the safety of nuclear power plants was carried out. All this allowed to determine the general requirements and methods of evaluation of software for various purpose. Results. Based on the results of the analysis of the current normative documents, the procedure for evaluating the software of systems of various purposes has been implemented in the TCC of LTD RPI HARTRON-ARKOS. Scientific novelty. This article formulates proposals for the extension of the standards of DSTU 4178 in the part of the assessment and proof of functional safety of software at the station level railway control systems. At the same time, the general requirements and methods of evaluation of software for different purposes, given in the current standards, were taken into account. Practical importance. The proposed approach of railway system software evaluation greatly extends the requirements of DSTU 4178 and facilitates the development and implementation of new, more effective software verification methods.

Method for Selecting the Safety Integrity Level for the Control-Command and Signaling Functions

The purpose of the article is to present selected method of risk assessment of railway control and signaling systems, including current normative and legal bases, such as directives and regulations that regulate the interoperability and safety of the railway system. Selected methods used at the initial stage of creating safety requirements and referring to the initial definition of the system defined at a high level of abstraction are considered. Issues of holistic approach and residual risk management are also discussed. Risk models are presented as well as individual steps of risk analysis, evaluation, and assessment, including hazard identification, impact analysis, and selection of the risk acceptance principle. Selected model based on hazard and operability studies (HAZOP) and an adapted risk graph was applied to the real signalling equipment. The key aspect undertaken in the article is the proposal to set quantitative safety objectives based on the safety integrity level/tolerable hazard rate (SIL/THR) indicator, as an important parameter in further analysis of the system, especially in computer applications. The result of study showed that application of proposed combination HAZOP and adapted risk graph method are efficient and suitable for a railway signalling application. The results and conclusion are presented in Chapters 4 and 6 of the article.

Rail information system prototype with web-based magnetic detection method

Trains are the most popular means of transportation by some people because it is cheap, fast, safe and comfortable. Because of carrying a sense of security, the construction of supporting infrastructure must be made safe, ranging from signs to the implementation of the door guard system in the railway crossing. Still often found in some railway crossing areas there is no guard door crossing system, so there are many accidents that resulted in the absence of a railway door guard system. The prototype was built to develop a railway control system by applying microcontroller technology, minicomputer and Hall effect sensor. The system will automatically detect the train that will pass by sending railway traffic safety information via the internet near the railway crossing. So that road users can find out early if there is a train that will pass by seeing the information monitor.

실시간 철도안전 통합 감시제어시스템의 데이터 분산 서비스 품질 적합성 분석

본 논문에서는 길시간 통합 철도 안전 감시 시스템의 데이터 전송 품질 요구 사항을 만족시키기 위해 OMG DDS 표준에서 제공하는 네트워크 전송 품질을 제어 할 수 있는 DDS(Data Distribution Service) QoS(Quality of Service)에 관한 실험을 통한 분석을 진행하였다. ‘실시간 통합 철도 안전 감시제어 시스템’ 은 철도 분야에서 다양한 센서의 데이터를 수집 및 분석하여 잠재적인 철도사고 위험을 예측하고 방지하는 시스템이다. 이 시스템에서 수집된 데이터를 정확하고 안정적으로 실시간으로 전송하려면 데이터 전송 품질을 보장해야 한다. 실험 결과에 따르면 DDS QoS를 사용하여 철도 안전을 모니터링하고 제어하기 위해 실시간으로 정확하고 안정적인 데이터 전송을 보장할 수 있다.