The high-speed train transmission system is a complex electromechanical coupling system. In this study, the torsional vibration of a train transmission system was studied. The centralised mass model of the mechanical structure of the coupling system was established. The natural vibration characteristics of the mechanical mechanism system were analysed. The results show that the natural vibration frequency of the universal shaft was 4.08 Hz, the natural vibration frequency of the pinion was 7.24 Hz, the natural vibration frequency of the big gear was 35.6 Hz, and the natural vibration frequency of the wheelset was 107.48 Hz. The traction motor model was built, and by considering the electromechanical coupling of the system, a torsional vibration suppression strategy for harmonic components in the motor is proposed. The effectiveness of the suppression strategy was verified by MATLAB/Simulink model simulation.

Inspection of physical surface defects is a significant concern in many industrial areas. In railway systems, this process mainly includes the detection and classification of defects in rails and wheels, for which laser-based optical inspection technologies have gradually been applied in the form of 2D profile measurement, benefiting from its high precision and robustness to surface conditions. However, defect classification and evaluation after the initial detection works still rely heavily on human inspectors to make maintenance suggestions. The linear nature of rails makes it possible to increase the dimension of rail measurement data from 2D to 3D by aligning 2D profiles along the rail, from which more comprehensive diagnosis information becomes available. In combination with appropriate artificial intelligence algorithms, this approach can potentially replace human-dominated defect classification and evaluation work. This study presents a 3D model-based railway track surface defect classification and evaluation method. A set of geometrical features are extracted from the 3D model of track surface defects to describe a distinguishable pattern for each category of defect. Multi-class classifiers are then tested and have shown promising results on a group of artificial track surface defects, giving a systemic solution for 3D model-based automatic track surface defect inspection.

Nowadays the railway industry is beginning to give serious consideration to using intelligent traffic management systems (TMSs) in order to improve railway performance regarding train and passenger delays and robust use of capacity. The TMS is responsible for handling railway traffic once a disturbance happens. A fundamental input parameter of a TMS is the train positions, to be used for traffic re-planning purposes. Inaccuracy in the train positioning data could significantly influence the effectiveness of a TMS. In this study, the authors developed a framework to evaluate how inaccuracies in the train position reporting may affect the TMS performance. This is achieved by assessing the impact of adding inaccuracies to the train position reported to a simulated TMS as it handles operational disturbances in real-time. The performance of the TMS is analysed by considering variability in overall delay outcomes after re-planning based on using accurate/inaccurate positional data. They demonstrate the usefulness of their framework in determining the positional accuracy required for the effective application of a basic rescheduling system via an example on a bottleneck area. Results show how the positioning inaccuracies can affect TMS and thus the overall delay.

Freight wagons typically do not have an electrical train supply and state-of-the-art auxiliary energy generation systems as, e.g. axle generators on freight wagons lack the possibility for a cost-effective retrofit. However, emerging applications, as, e.g. anti-lock braking systems for freight trains or condition monitoring systems for the loaded goods, require electric power in the watt range. Therefore, a non-invasive auxiliary energy supply system with 22 W/dm³ (360 mW/in³) based on a non-coaxial eddy-current coupling is described and analysed in this study. It is a kinetic energy recovery system, which can extract power directly from the motion of a freight wagon's wheel. An air gap of 10 mm between the wheel and a permanent magnet rotor is set during operation, making the system a non-invasive one. A model for the transfer efficiency of the system is established and verified by measurements. The prototype including an optimised generator and an integrated active rectifier for generating a DC-output voltage is built and an electric power of 8 W can be extracted from a steel wheel moving with a surface speed of 22 m/s.

The high-speed train transmission system is a complex electromechanical coupling system, which consists of a motor, a universal shaft, a gearbox, and a wheel set. In order to solve dynamic problems such as torsion vibration caused by a high-speed train transmission system, the simplified model and equivalent mechanics model of the system were established, the natural vibration frequency was solved, and the simulation results of the system under a fixed torque input were analysed. The results showed that the natural vibration frequency of the universal shaft was 4.19 Hz, the natural vibration frequency of the pinion was 7.54 Hz, the natural vibration frequency of the big gear was 35.6 Hz, and the natural vibration frequency of the wheel set was 107.45 Hz. The natural vibration frequency of each part of the system increased gradually during the transmission from the motor to the wheel set. A fixed torque was added to the input end of the simulation model. The simulation results showed that the change amplitude of the torsion angle displacement of the big gear and the wheel set decreases. It is known that the angular displacement caused by the torsional vibration is weakened by the larger torsion stiffness of the axle.

RINA have determined a number of key areas of focus for rail industry suppliers to ensure that their safety arguments support their end customers CSM RA processes. These are: a clear and up to date Safety Plan, a clear description of the boundaries of supply (equipment and organisational), evidence of a thorough determination of possible hazards, a clear and complete Hazard Record, and clear arguments as to the applicability and use of Codes of Practice and Reference Systems. In this paper RINA presents effective methods to support supplier in achieving these goals.

Infrastructure managers (IMs) endeavour to eliminate rail defects at an early stage since they impact on safety and quality of operation and increase system costs. London Underground (LUL) uses several non-destructive testing (NDT) techniques in rail inspection to detect the emerging defects and monitor the growth of previously recorded defects. This task mainly aims to prioritise maintenance and renewal activities and record their completion. However, when the high traffic demand and limited maintenance periods are considered, these requirements bring additional pressures to the maintenance team. To optimise maintenance planning, sufficient and reliable field data along with accurate damage prediction are required. Recent developments in NDT technology has seen the introduction of devices to measure crack depth which is a key parameter in the assessment of crack severity and rail life. Therefore, contrary to previous research which mainly utilised observations of rail surface condition, the use of new NDT techniques can support the development and validation of new rail damage models which will help to improve maintenance planning and move to condition-based maintenance strategy.

Platform screen doors (PSD) are the sliding barrier doors installed at the edges of station platforms in many modern metro stations and occasionally on heavy rail systems. They serve many functions among which are the suicide prevention, optimisation of station energy consumption and safety, particularly by shielding passengers from gaining access to the rail tracks. PSD can prolong dwell time, increase the danger of mantrap and can extend emergency evacuation periods, among others. These pave way for the existence of PSD to have both positive and negative effects on the railway system. This research identified the benefits that could be derived from installing PSD at train stations and the drawbacks associated with its presence, with a view of evaluating the overall effects that the PSD has on the railway system. Upon identification of both factors, a causal loop diagram (CLD) has been developed to enable a pictorial demonstration of the various PSD effects, their systematic interrelations, the polarity of effects, and how they combine to affect the entire railway system. The conclusion reached in the present study was that PSD as a system can have significant impact on many aspects of the railway such as delays, capacity, safety, platform climate control, energy consumption, air quality and so on. But there are no studies that attempt to combine them all into an overall evaluation.

Metro Trains Melbourne (MTM) strives to provide a safe, reliable and available passenger rail service throughout the metropolitan network, through the delivery of over 14,000 services each week utilising 3 different rolling stock fleets. Through customer feedback and identification of prematurely wearing bogie components, the Comeng vehicles fitted with BradKen cast frame bogies exhibited poor ride quality at speeds higher than 100 km/h, which was being exacerbated by increased passenger loading. This led to an investigation of the ride quality, the objective of which was to identify the reasons behind the poor ride quality and to improve the dynamic performance of the vehicle, making for a more comfortable ride for commuters and a reduction in maintenance costs. In-service testing was initiated by instrumenting a trailer bogie on a revenue train to identify the severity of the poor ride quality and any potential correlation to geo-locations. This exercise identified the root causes and potential configuration changes necessary for the bogie. A computer model of the bogie was developed and multi-body simulations carried out using Universal Mechanism (UM, www.umlab.ru) to identify potential solutions to improve the ride performance, the basis of which was validating the computer model simulation results with the inservice test results. Multiple simulation iterations led to the identification of the appropriate configuration change by varying the primary vertical damping rate. Further field testing was carried out to validate the simulation predictions. This paper discusses the testing, analysis and modelling methods used, and some of the innovative approaches explored, to identify and rectify the bogie's poor dynamic behaviour.

This paper offers support and guidance on a major infrastructure subsurface railway project, to select and undertake an effective reliability, availability and maintainability and safety (RAMS) strategy. RAMS which forms part of systems engineering is an essential discipline and integrated in most railway undertakings. How projects choose to undertake this discipline is subjective, and can be different from project to project. The principle of the paper covers Crossrail methods primarily in the central area of the project. The paper is intended for railway operators (RO) and delivery organisation (DO) which includes the supply chain and RAMS practitioners of such work.