Suspension parameters optimisation and matching is a very important topic in the design of railway vehicles, and a reasonable combination of suspension parameters is the most powerful guarantee for safe and stable operation. However, most of the existing research about that still belongs to single-objective optimisation and pays little attention to the matching relationship between different suspension

In this paper, a new control algorithm for active suspension systems is presented. Latter is designed to improve low frequency comfort, which gains importance with autonomous driving and the possibility for nondriving tasks like in-car working. The algorithm is based on model predictive controllers and makes use of environment sensor information and extends preview by taking the future trajectory of

For the development of condition monitoring algorithms for turnouts, an extensive dataset consisting of measurement and simulation results is required. The basis for reliable simulation results are precise and easy applicable measurement techniques of the turnout geometry, like 3D handheld scanners. The challenge in using the data from portable 3D scanners for vehicle/track interaction simulation lies

ABSTRACT Starting from the earliest phases of design of the vehicle and its control systems, the understanding of tyres is of fundamental importance to govern the overall vehicle dynamics. A properly characterised tyre–road interaction model is essential to achieve a reliable vehicle dynamics model on which more design variations can be studied directly in simulation environment optimising both cost

The design and maintenance of turnouts implies considering a great number of external factors that have an effect on their structural integrity. The proper generalised decomposition (PGD) method is used in this paper to carry out a parametrised study of the vehicle-track interaction in a non-intrusive way. The reduced model is built using a defined domain for some of the influence parameters: the vehicle

Wheel climb derailment frequently occurs in turnouts. This is usually because track alignments in the turnout area are very poor and the cross-sections of switch rail are not uniform. Most previous studies focused on derailments in straight or curved lines. For this reason, understanding the derailment mechanism in turnouts and revealing the influence of the wheelset motion conditions on dynamic derailment

Vehicle safety is an important field of today's engineering practice and the scientific research as well. One of the basics of the modern vehicle system dynamics control systems is braking or driving torque control. Ensuring proper connection between the tyre and the road surface is essential for safety and good handling behaviour. Fundamental questions may arise about the details of the model, such

This work addresses the design of an active fault-tolerant motion controller for over-actuated road vehicles. Our concept revolves around a control allocation framework, extended with Lyapunov-based stability constraints and costs. Besides the ability to cope with actuator constraints and optimal actuator reconfiguration, the proposed Lyapunov-based control allocation (LCA) allows the graceful degradation

To investigate the dynamic effects of bolster-hanger length on the 600 km/h high-speed EMS maglev vehicles, a dynamic model of three-car trainset is established, considering the kinematic relation of the bolster-hanger mechanism and the active levitation/guidance control system. Model validation is carried out by comparing simulated results with test results of Shanghai high-speed maglev vehicles.

Motorcycle designers aim to enhance vehicle performance, stability, and safety, especially when the vehicle is approaching the tyres' friction limit. A strategy to achieve these purposes is to design All-Wheel Drive (AWD) vehicles with active torque distribution. Nowadays, effective technical solutions for powering the front wheel of a motorcycle have been proposed. The use of traction on both front

This paper proposes two different approaches for estimating grade and bank angles for arbitrary vehicle-trailer configurations independent from road friction conditions: model-based and Machine Learning (ML) approaches. The model-based method employs unknown input observers on a vehicle-trailer roll/pitch dynamic model with fault thresholds. In the proposed ML approach, a Recurrent Neural Network (RNN)

This paper proposes a new model of the cylindrical pin coupler and buffer system and then a more accurate train dynamic model to investigate the heavy-haul locomotive dynamic performance and running safety. In this new model, the buffer bias pressure characteristic is simulated accurately by discretising the real polymer buffer linearly into seven impedance force elements of the same non-linear hysteresis

In railways, using a track- and ride-quality monitoring system on in-service train has become desirable for coordination and security. Identification of the track- or train-related rough rides via train crew can be estimated to the nearest kilometre. However, if the train is equipped with a monitoring system a better location and track quality evaluation can be provided. These systems commonly use

Minimum-lap-time simulations with quasi-steady-state models and predefined trajectory have been in use for many years. However, most of the published works deal with two-dimensional roads and employ the so-called apex-finding method. This paper focuses on the application to three-dimensional roads, both with an extension of the ‘apex-finding’ approach to three-dimensional scenarios and with an optimal

In this note an explanation and the relevance of a couple of singularities in the mathematical models of rolling friction is presented.

Pantograph hardware-in-the-loop (HIL) testing is an experimental method in which a physical pantograph is excited by an actuator which reproduces the movement of a virtual catenary. This paper proposes a new method that uses analytical catenary models for HIL tests. The approach is based on an iterative scheme until achieving a steady-state regime. Some of the method's advantages include its ability

A Benchmark of railway multibody dynamics software application to switches and crossings (S&C) is presented, comparing all major commercially available software and a few independent codes. Two different representative S&C have been implemented, using the Manchester Benchmark passenger vehicle. The final results show that all software offer a reliable and efficient way to understand the kinematic and

The speed profile of a train plays an important role in energy consumption and resulting costs. The industrial objective of this work is thus to develop a method to reduce the energy consumed by a train over a journey by playing on the driver commands (traction and braking forces) while respecting punctuality constraints. First, a rigid body approach (Lagrangian formalism) is introduced to characterise

In addition to the discontinuity of the rail profile of a normal turnout, the unique S-shaped curve of a crossover significantly affects the negotiation performance of a train. For heavy-haul freight trains, the in-train forces generated during the braking process may further deteriorate the running safety. Investigating the dynamic behaviour of the train passing through the crossover under braking

Generally, the equivalent conicity function (ECF) is denoted by equivalent conicity at 3mm (λ3mm) and a Nonlinearity Parameter (NP). NP describes the nonlinearity of the ECF and its influence on a vehicle design is explored thoroughly, however, NP’s role in vehicle and track maintenance is not researched yet. This paper investigates the influence of track maintenance actions on vehicle dynamics with

This paper is a study on a novel configuration switchable hydraulically interconnected suspension (CSHIS) system based on nonlinear model predictive control (NMPC). The proposed CSHIS system has significant improvements in stability and performance than the existing CSHIS systems. The CSHIS system uses a direction valve for configuration switching, and improves the overall vehicle dynamic performances

Railway vehicle dynamics is strongly affected by track irregularities, which can influence the safety and the running behaviour of the vehicle. The EN 13848-5:2017 standard provides the limits of track irregularities for standard track but does not states specific restrictions for switches and crossings. Furthermore, since turnouts have a limited length, their track geometric irregularities cannot

With the expansion of urbanisation, more and more metro vehicles shuttle on dedicated railway lines, leading to serious wheel wear and reduced passenger comfort, it is therefore of interest to design a wheel profile that matches well with the dedicated lines. This paper presents a wheel profile optimisation procedure consists of 3 steps. Firstly, taking the LM profile, which widely used in China metro

The improved delayed detached-eddy simulation (IDDES) method was used in this study to explore the influence of windbreak wall end shape on the wind tunnel test of the high-speed train aerodynamic characteristics. Affected by three different types of windbreak walls (long-enough, rounded-end, and blunt-end), the aerodynamic force, pressure distributions on the train surface, and flow fields around

The feasibility of automated railway track segment characterisation, as part of a broader track condition based maintenance procedure, is explored via railway–vehicle–based random vibration signals and Statistical Time Series (STS) methods. In particular, three methods within a Multiple Model (MM) framework, which are founded on data-driven stochastic parametric models for the representation of the

This paper presents the final description for the S&C Benchmark that was launched at the IAVSD 2019 conference held in Gothenburg, Sweden and completed by eighteen participants by the end of 2020. The purpose of this paper is to allow for the replication of the Benchmark exercise after publication for those who wish to do so in the future, and it includes a link to the repository containing all necessary

The superconducting electrodynamic suspension (EDS) train, which has reached a manned speed of 603 km/h in 2015, and is therefore regarded as one of the most attractive technologies for the higher speed train. In the superconducting EDS train, the discrete layout of ground null-flux coils causes the additional electromagnetic ripples towards the bogies, making the vibration control more essential to

Vehicle-track interaction in a switch panel diverging route is studied with a focus on the way its components may interact in the lateral direction. Taking one of the cases of S&C benchmark as the base model, several variants of the co-running track model are considered. In the first series of simulation, the effect of the lateral separation of the switch rail and stock rail is investigated, showing

Wheel wear is a natural phenomenon of wheel–rail rolling contact during vehicle operation. The non-uniform wear in lateral and circumferential directions is normally occurred on wheels. The lateral non-uniform wear will lead to the unexpected hollow wear which can cause flange to flange vibration at low-frequency band, and the circumferential non-uniform wear will result in the vertical vibration which

Irregularities of rail joints ordinarily induce high-frequency impacts on wheel–rail contact systems, which may further influence vehicle–track interaction. In this study, a three-dimensional locomotive-track coupled dynamics model that uses the wheelset flexibility was developed. The wheelset rigid motion and elastic deformation are calculated based on the multi-body dynamics theory and finite element

(2021). IAVSD 2021 – the 27th symposium on dynamics of vehicles on roads and tracks. Vehicle System Dynamics: Vol. 59, State of the Art Papers of the 27th IAVSD Symposium guest edited by Anna Orlova, Yuri Boronenko and Alexander Tretyakov, pp. 975-975.

The era of the electrification of vehicle drivelines is rapidly approaching. Motors are capable of providing controls with response and accuracy two orders of magnitude greater than internal combustion engines. It is also relatively simple to design a driveline capable of independently controlling the driving force at each wheel by providing compact motors throughout the vehicle. Although the potential

This paper surveys advances in the understanding and modelling of wheel–rail creep forces. The main focus is placed on tribological aspects, for which significant progress was made in the past two decades. We emphasise the role played by the surface conditions, i.e. the presence of liquid and solid layers, surface roughness, and near-surface plastic deformation. As these surface conditions may change

This review addresses efforts made within the field of vehicle dynamics to contribute to the energy efficient operation of road and rail vehicles. Selected investigations of the research community to develop technology solutions to reduce energy consumption are presented. The study explores the impact and potential of relatively mature technologies such as regenerative braking, but also recent research

The paper demonstrates the possibilities of a scientometric approach using CiteSpace II software analysis of the field of railway dynamics with detection of research front, main clusters of cross-cited papers, their evolution and pivotal points (see terms in Sections 2.1 and 2.2). The initial database contained 5126 Web Of Science records published between 1975 and 2019 (45 years). The linguistic analysis

In this paper, the effect of strip spacing on the aerodynamic performance of a high-speed pantograph with a double-strip is numerically studied using a shear stress transport turbulence model. Seven different strip spacings varied from 100 to 700 mm are considered. The errors in pantograph resistance between numerical simulation and wind tunnel test are within 5% in both knuckle-downstream and knuckle-upstream

Hunting causes accelerated wear and damage to bogies, track and the lading carried by railway wagons and can, in conjunction with track geometry irregularities, lead to derailment. Simulation can be used to estimate the critical speed below which sustained hunting will not occur given certain parameters of the wagon, track and lading. This paper investigates the hunting of an unloaded freight wagon

Nonlinear effects and external disturbances can severely impact the control of an autonomous race car at the handling limits. State-of-the-art approaches do not take these uncertainties explicitly into account in the design process and are therefore prone to failure. To overcome this limitation, we present a robust control design based on tube model predictive control (TMPC). It is based on a simplified

For a high-speed rail vehicle with gauge-changeable wheelsets, wheel/rail interactions and vehicle dynamics were numerically and experimentally studied within 600 km/h. Matching among four treads, three rail profiles, two gauges, and two rail cants are analysed by examining the wheelset conicity, contact points distribution, and stress. It shows that the conicities of the S1002 and LMA become smaller

The article presents the results of theoretical studies of interaction process of a freight car body with a three-piece bogie, which are aimed at solving the relevant problem of increasing the permissible speeds at railways with 1520 mm track gauge under conditions of linear load increase on the wheel set axle. The purpose of the research was to propose such an approach to the study of interaction

A new state observer-based vibration control strategy for the suspension system equipped with magnetorheological (MR) damper is proposed in this paper. Firstly, the Bouc-Wen model is implemented to fit the hysteresis phenomenon of the MR damper. A new dynamic model is successfully formulated including the Bouc-Wen model and electrical equation. According to the energy conservation law, an adjustable

Rail irregularity presents a major threat to the high-speed train (HST) safety on a high-speed rail (HSR) bridge. Lateral bridge deformation has a significant impact on geometric parameters of the rail. In this paper, the influence of lateral bridge deformation on the train operation on the HSR bridge is investigated. Variational calculus is employed to establish the analytical mapping between the

Solving the wheel-turnout contact geometry is complex because the rail section is varying along its longitudinal position. Besides, a large yaw angle will occur, especially when the vehicle passes the switch panel in a diverging route. However, previous researches seldom considered the aforementioned factors simultaneously in performing wheel–rail local contact analysis. This paper therefore proposes

Aiming at preventing frequently occurred coupler jack-knifing in slave control locomotives of 20,000-tonne heavy-haul trains, a theoretical and experimental research on enhancing the coupler stability has been carried out. Field tests are conducted to ascertain the load characteristics of the slave control locomotive, and the coupler stability mechanism of the locomotive is studied. A dynamic simulation

Relative to the Hertzian theory, the non-Hertzian contact model (NHM) can better reflect the contact characteristic between wheel and rail in railway vehicle dynamics simulation. In this paper, an optimal wheel-rail tangential contact model is determined for vehicle dynamics simulation. First, based on i) the modified Kik–Piotrowski (MKP) contact model, ii) four different ellipse-equivalent methods

This paper presents a method for the optimisation of wheel–rail profiles, and this is based on the relationships between the equivalent conicity, RRD curve and rail profile slope. This method can be used to improve the riding stability of trains when rolling across turnouts, and to optimise the equivalent conicity. The measured profile of a straight switch rail, i.e. a 60D40 rail laid in a high-speed

Crosswinds affect vehicle driving stability and their influence increase with driving speed. To improve high speed driving stability, interdisciplinary research using unsteady aerodynamics and vehicle dynamics is necessary. The current demands of faster development times require robust virtual methods for assessing stability performance in early design phases. This paper employs a numerical one-way

The near fault (NF) line waves send out signal envelopes that oscillate over lengthy periods of time with periodic impulses. Like train bridges, train tracks demonstrate comparable track-bridge (TB) motion dynamics. Using these coupling dynamics, are the high-speed train-track-bridge (HSTTB) system designs sensitive to those parameters? This research incorporates a Finite Element Analysis (FEA) technique

This article presents an efficient methodology for the calibration and validation of a numerical model of a freight wagon based on a dynamic test under real operation conditions. The dynamic test takes place during a regular journey of the train and involved the installation of on-board accelerometers and LVDTs, whose number and location was conditioned by the space occupied by the goods and constraints

In earlier work, a driver model incorporating sensory dynamics was identified from driving simulator experiments involving random disturbances, random target paths and linear vehicle dynamics. In the present paper, the driver model and experiments are extended to include transient disturbances, discrete target paths and nonlinear vehicle dynamics. The predictions of the model are compared with measurements

A coupled track-train-seat-human model with lateral, vertical and roll vibrations was developed to investigate the ride comfort of high-speed trains. The ride comfort was assessed by the total equivalent acceleration defined according to ISO 2631-1. It was found that the track flexibility had a minor influence on the lateral, vertical and roll floor vibrations below 20 Hz, while the total equivalent

Due to local resonances, high vibration levels occur frequently in high-speed train floor, which impact on the ride comfort negatively. A method to control excessive local vibration with multiple dynamic vibration absorbers (DVAs) is presented. Firstly, possible causes of the high vibration levels are investigated with operational and modal tests. Then a model of the vehicle body with multiple DVAs

To fully consider the influences of the exciting frequency (0–20 Hz) and the environmental temperature (−50–20°C) on the dynamic characteristics of the rubber bushing in the railway vehicle, a hybrid neural network model is applied to develop the detailed model of the rubber bushing. The nonlinearities of the rubber bushing existing in the elastic element, the friction element and the viscous element

A good understanding and modelling of the human driver is essential for modern vehicle development, particularly in motorsports, where the race car should fit its driver perfectly. At the same time, an objective assessment and especially imitation of professional race drivers is difficult due to individual driving styles, complex and non-deterministic decision making processes, and small stability

A novel method is proposed to suppress the flexible carbody resonance due to bogie instability by hanging a dynamic vibration absorber (DVA) to the bogie frame. The aim is to design the DVA to change the frequency of the bogie hunting motions, which can ensure the bogie does not operate at the resonant frequency of the objective mode of the flexible carbody. Firstly, the resonance phenomenon of the

Gear transmission is an essential element in the motor cars of high-speed trains, as it directly effects the reliability and safety of the vehicle. Based on the classical vehicle–track coupled dynamics theory, and gear and bearing dynamics theory, this investigation develops a novel vehicle–track coupled dynamics model with an enhanced gear transmission subsystem comprising gear pair and bearing. In

Axles with leaf spring suspension systems are still a popular choice in many commercial vehicles. However, leaf springs are not in perfect conformity to standard multibody vehicle models because they combine guidance and suspension in one single element. Combining standard multibody vehicle models with sophisticated finite element leaf spring models results in rather complex and computing time-consuming

In order to identify the road friction coefficient of the left and right sides of the vehicle more accurately, this paper presents an estimation framework based on a novel tyre model and modified square-root cubature Kalman filter (SCKF). To begin with, a novel tyre model is proposed by adaptively calculating the longitudinal and lateral stiffness and the effective friction coefficient. The tyre forces

Advanced control and driving assistance systems play a major role in modern vehicles, ensuring higher standards of safety and performance. Their correct operation extensively depends on the knowledge of tyre forces and vehicle drift. However, these quantities are hard to measure directly, due to cost or technological reasons. One possible alternative that is attracting much attention in the last few

It has been recently pointed out that railway vehicle passengers do not behave as inert masses but as dissipative elements: they increase modal damping without significantly affecting the natural frequencies of the carbodies. The phenomenon is more prominent in current lightweight high-speed railway vehicles, because weight reduction is usually attained at the expense of reduced stiffness. The few