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

Controlling greenhouse gas emissions is becoming increasingly more important. With road freight contributing to a significant amount of energy usage, finding ways to improve this sector will, in turn, lead to large reductions in carbon dioxide emissions, with one method to achieve this being to use larger vehicles. Currently, prescriptive legislation dictates the dimensions a vehicle can take. An alternative

ABSTRACT Rear-wheel steering has seen new popularity in recent years. Many explanations of rear-wheel steering systems use the concept of a ‘virtual wheel base’ to explain in-phase or out-of-phase steering. This paper introduces a novel reference model that realises this metaphor. A reference model is created where its wheelbase can be changed arbitrarily, making the resulting system intuitive and

For railway locomotive, its motor bearing is one of the key components, which is likely to be damaged due to the intensified vibration conditions caused by the wheel-rail interaction and gear mesh. In this paper, a locomotive-track spatially coupled dynamics model considering the dynamic effect of the traction power transmission is established to investigate the dynamic responses of traction motor

This work elaborately conducts the coupled vibration analysis of suspended monorail train and curved bridge (SMTCB) considering a nonlinear wheel-track contact relation. First, a high-efficiency coupled dynamic model of the SMTCB is developed based on a co-simulation method where the train subsystem is established using the multi-body dynamics software UM and the curved bridge subsystem is built adopting

Damage of rail fastening system often occurs due to severe vehicle-track dynamic interactions. To evaluate the dynamic performance of the rail fastening system subject to dynamic interactions between vehicle and track, a refined vehicle-track coupled dynamics model involving an elaborated model of rail fastening clip (RFC) is developed in this work. Firstly, the RFC model is established based on the

This paper deals with the lateral force effects of conventional four-axle railway vehicles in conditions of S-shape curves, which are represented especially by switches negotiated in the diverging direction. With the use of a multi-body model of an electric locomotive, a sensitivity analysis of selected vehicle parameters on the maximum guiding force in the S-curve is performed. Subsequently, a definition

The railway companies have been beset by rail corrugation for many years, especially those subway companies. Therefore, the formation mechanism of rail corrugation has been paid much attention in the last decades. It is believed that corrugation occurs when the vehicle runs over the track and excites its resonant vibration. Wheel polygonal wear (WPW), as a typical wheel tread defect, inevitably worsens

The aim of this work is to introduce a new concept for a hydraulic semi-active yaw damper (SAYD) for the improvement of the stability of a high-speed rail vehicle. This concept represents a further elaboration of Secondary Yaw Control but envisages the use of semi-active hydraulic dampers instead of full-active electromechanical dampers, simplifying the design of the system and facilitating the design

Railway track irregularities occur naturally from service operations and are characterised by deviations of the track relative to its nominal geometry. Since the dynamic behaviour of a rail vehicle depends on the geometry of the track, studying irregularities is essential for safety, comfort, and maintenance. Conventionally, an irregularity is synthesised from a univariate stochastic process, which

This paper investigates the handling control and stability of an all-wheel-drive vehicle whose axles are individually equipped with an electric motor connected to an open differential. This could offer a potential configuration for the mass production of electric all-wheel-drive vehicles because of reduced cost and complexity. Although there is no torque vectoring or direct yaw moment control in this

Assembly deviations of wheelsets cause differential wheelset misalignments and change the wheel-rail contact relationship in railway turnouts. In this paper, the motion conditions of wheelsets under the same bogie are analysed with differential wheelset misalignment based on the mechanical equilibrium condition. A rigid-flexible coupling model of vehicle-turnout dynamic interaction that fully considering

The paper begins with a survey of advances in state-of-the-art minimum-time simulation for road vehicles. The techniques covered include both quasi-steady-state and transient vehicle models, which are combined with trajectories that are either pre-assigned or free to be optimised. The fundamentals of nonlinear optimal control are summarised. These fundamentals are the basis of most of the vehicular

Dimensional analysis has been very helpful in experimentation of very large or small-scale engineering systems. A good example would be experimentation on the aircrafts and ships, which was made cost-effective and simple by dimensional analysis. The history of dimensional analysis mentioned in the introduction section of the present document includes many of such applications. Automotive industry,

Tire hydroplaning is a phenomenon that occurs when the tire is no longer able to evacuate water from the road due to excessive speed. A water layer will then be interposed between the tire and the road, reducing their contact surface and decreasing the tire’'s ability to transmit forces. The purpose of this work is to analyse this loss of contact surface through the experimental point of view with

Autonomous vehicles allow utilisation of new optimal driving approaches that increase vehicle safety by combining optimal all-wheel braking and steering even at the limit of tyre–road friction. One important case is an avoidance manoeuvre that, in previous research, for example, has been approached by different optimisation formulations. An avoidance manoeuvre is typically composed of an evasive phase

Future vehicle localisation technologies enable major enhancements of vehicle dynamics control. This study proposes a novel vehicle stability control paradigm, based on pre-emptive control that considers the curvature profile of the expected path ahead in the computation of the reference direct yaw moment and braking control action. The additional information allows pre-emptive trail braking control

Indirect tire pressure monitoring system monitors inflation pressures in pneumatic tires using wheel speed sensor (WSS) signals acquired from anti-lock braking system. In order to monitor the tire pressures indirectly, frequency analysis and wheel radius analysis are operating in parallel. This paper focuses on the frequency analysis. The resonance frequency of tire torsional vibration decreases as

The friction draft gear with hysteresis characteristics is one of the typical nonlinear elements in longitudinal train dynamics (LTD). Due to the nonlinear hysteresis of friction damping, the discontinuity between loading and unloading envelopes becomes a mathematical integration issue when adopting look-up table methods to establish draft gear models. It might cause integration divergence and wrong

ABSTRACT An increase in electric railway vehicles service velocity requires that correct interaction between the pantograph and the catenary is ensured. This implies the need for developing mathematical models of pantographs and catenaries and determining their parameters. The article presents a method to determine parameters of mechanical joints of a railway pantograph based on analysis of pantograph

This research presents a rule-based Anti-lock Braking System (ABS) algorithm towards active vehicle safety in Heavy Commercial Road Vehicles (HCRVs). Wheel Slip Regulation (WSR) algorithms, that are constituents of an ABS, are typically either model-based or rule-based. Model-Based Algorithms (MBAs) utilise mathematical models that characterise vehicle dynamics and are intensive in their demand for

Wheel/rail dynamic interactions of heavy-haul locomotives are highly nonlinear and complicated due to large traction/braking loads, frequent anti-slip control and complex wheel/rail interface environment. The wheel/rail dynamic interactions, as well as the interface wear, have been broadly studied by means of Hertzian contact analysis, but the wheel/rail contact is essentially a non-Hertzian contact

A new phenomenon has occurred during a full-scale test in which the maximum overturning coefficient did not appear at the maximum wind speed or the highest operating speed when a train negotiates wind speed variations along a section of railway. This study focused on this challenge, and conducted an experimental-numerical study of the relationship between the car-body initial dynamic sway and the operational

It is well known that wheel wear degrades the dynamic performance of the rail vehicles, especially in regard to the issue customarily known as ‘running stability’ and resulting in the evaluation of the vehicle’s critical speed. Past research addressed this problem mainly from the viewpoint of the influence on the vehicle performance of the wear pattern. The aim of this work is to investigate the influence

Rolling stock approval protocols, such as UIC 518, demand monitoring of lateral and vertical forces at rail-wheel contact. Continuous monitoring through on-board instrumentation needs algorithms to convert the on-board sensor data into rail-wheel forces and track irregularities. In this work a Feed Forward Neural Network architecture, for fast and accurate estimation of rail-wheel forces and track

Accurate tyre models are important to ensure valid and reliable simulation of vehicle behaviour. To this purpose, the Magic Formula (MF) became the de facto standard for vehicle dynamics simulations, despite requiring many empirically derived coefficients. This paper shows how the accuracy of a simple physical-based brush-type tyre model can be enhanced to simulate tyre behaviour that closely matches

With increasing transportation speed, the excessive vibrations of high-speed trains (HSTs) have become a critical issue to be solved. This study presents an innovative semiactive suspension system consisting of a magnetorheological (MR) damper in parallel with a magnetic negative stiffness (NS) element. The proposed semiactive dampers, called MRNS dampers, are integrated into the secondary suspension

Field measurements of the elastic vibration of a car body (CB) and its coupling with the underframe equipment vibration were carried out for a high-speed railway vehicle, it was found that there was a significant increase of CB elastic vibration when passing a particular location and the equipment absorbed little of the CB vertical elastic vibration. In order to reduce the CB elastic vibration, the

ABSTRACT Automated steering technology offers significant benefits to the safety of vehicles, but desire to keep the human driver in the loop requires a better understanding of the interaction between driver and vehicle. An existing noncooperative–game–theoretic framework for modelling such interaction is revisited, leading to the development of two driver steering control models. Both bear Nash–equilibrium

The simulation of vehicle chassis system is widely deployed at the early stage of a new car development project in order to verify if the technical specifications such as durability and comfort of current design are fulfilled. However, the numerical validations of specifications are usually carried out independently by project teams, which may fail to converge the final design at downstream phase of

The high-speed train needs excellent curve-passing performance, reducing wheel/rail force and wear, and sufficient hunting stability. According to the mechanism of self-steering radial bogie, the Interconnected Hydro-Pneumatic Steering system (IHPSS) is adopted as the primary longitudinal suspension element to realise the wheelsets’ radial function. Four struts of the IHPSS are mounted between the

The rail fastener plays an important role in supporting the rail and isolating the train-track system vibrations. Its damage detection is therefore an inevitable part in railway maintenance to ensure the system performance. Recently, deep learning techniques are widely applied to structural health monitoring, including damage detection of the rail fastener based on visions. However, the vision-based

The paper proposes the implementation of a control system for a variable-geometry suspension to achieve steering functionality. The implementation is performed in a Hardware-in-the-Loop (HiL) simulation environment with a unique suspension test bed. The purpose of the control system is to achieve path-following functionality for the vehicle with automatic steering based on the proposed system. The

ABSTRACT Rail accelerations can be used on the defect detection and health monitoring of railway vehicle and track components; therefore, mathematical models that predict this response are of interest for reproducing its behaviour in a wide range of situations. The numerical track models based on the Timoshenko beam theory introduce a non-physical response, which is especially noticeable in the rail

The drive torque for each motor can be performed independently for the distributed drive electric wheel loader (DDEWL). On the shovelling condition, the torque distribution can be optimised according to the tire load. Then the parasitic power and wheel slippage can be reduced, and the tractive force and efficiency are improved. In this study, the singular value decomposition unscented Kalman filter

The road condition is complex and variable during driving; hence, the suspension system cannot easily suppress the vertical vibration of the vehicle. To effectively improve the vehicle dynamic performance under different road conditions, this study proposes a switching control strategy for the semi-active suspension based on the road profile estimation. First, the mapping relationship between different

ABSTRACT This study deals with drifting as one of the most important nonlinearities in vehicle dynamics. A four-wheel vehicle model is used to calculate the equilibria in planar motion, numerically, by introducing an assumption on constant longitudinal tyre slips. Other than the unstable drifting points that were reported by previous researchers, a new pair of drifting equilibria are identified and

The draft gear is a key component in a railway train system. The stochastic feature of dry friction in the draft gear has been observed by many researchers, however, characterisation studies in this regard have not been published. This paper used a state-of-the-art laboratory testing rig to measured draft gear forces and deflection responses to sinusoidal force inputs. Measured data were then inversed

Development of railway transportation capabilities towards high-power, high-speed and heavy axle-load makes the dynamic interactions between the electric drive subsystem and the mechanical subsystem of a locomotive more intensive and complicated, which may threaten the locomotive operational safety. However, the included dynamics mechanism and influencing law have not been revealed completely. Based

ABSTRACT For modern electrical rail systems, the pantograph-catenary dynamic performance is one of the most critical challenges. Too much fluctuation in contact forces leads to either accelerated wear of the contacting components or losses of contact and, consequently, arcing. In this work, inertance-integrated pantograph damping systems are investigated with the objective of reducing the contact force

Railway track models with sloped subgrade ends, are commonly used in studies of train. In the present work, the effect of subgrade-end slope under a yaw angle of 30° was investigated by delayed detached eddy simulation (DDES) using one-eighth-scale train and single-track rail models. The obtained results were validated with wind tunnel tests. Time-averaged aerodynamic coefficients, pressure distribution