Active Steering Bogie Research Articles

Dynamic performance evaluation and optimization of steering rail vehicle based on sensitivity sequence

In this study, dynamic models of three bogies— traditional bogie (TB), active steering bogie (ASB), and forced steering bogie (FSB) —were established to clarify the similarities and differences between them in the parameter optimization design of dynamic performance. The first- and second-order sensitivities of the effects of the vehicle dynamic parameters on the wear, running stability, and riding comfort were obtained based on the global sensitivity method. According to the results of sensitivity analysis, the ASB and FSB primarily focus on changing the steering mechanism of the TB in the curved track and have insignificant effect on the running stability and riding comfort. Next, the dynamic performances of the three vehicles were evaluated using the control variable method. The results indicate that the ASB and FSB could change the parameter optimization method of TB, mainly because the contradiction between wear and running stability need not be considered when key parameters are in the feasible region, and the optional range of parameters is further widened. Finally, parameter optimization methods for different vehicles were formulated based on a comprehensive dynamic performance function.

Analysis on Steering Performance of Active Steering Bogie According to Steering Angle Control on Curved Section

In this paper, prior to the commercialization of a developed active steering bogie, we want to analyze steering performance experimentally according to steering angle level with the aim of obtaining steering performance data to derive practical design specifications for a steering system. In other words, the maximum steering performance can be obtained by controlling the steering angle at the 100% level of the target steering angle, but it is necessary to establish the practical control range in consideration of the steering system cost increase, size increase, and consumer steering performance requirements and commercialize. The steering control test using the active steering bogie was conducted in the section of the steep curve with a radius of curvature of R300, and steering performance such as bogie angle, wheel lateral force, and derailment coefficient were analyzed according to the steering angle level. As the steering angle level increased, the bogie indicated that it was aligned with the radial steering position, and steering performance such as wheel lateral force and derailment coefficient was improved. The steering control at 100% level of the target steering angle can achieve the highest performance of 83.6% reduction in wheel lateral force, but it can be reduced to about one-half of the conventional bogie at 25% level control and about one-third at 50% level. Considering cost rise by adopting the active steering system, this result can be used as a very important design indicator to compromise steering performance and cost rise issues in the design stage of the steering system from a viewpoint of commercialization. Therefore, it is expected that the results of the steering performance experiment according to the steering angle level in this paper will be used as very useful data for commercialization.

Influence of active steering with adaptive control law on a metro rail vehicle wheel wear and dynamic performance

An active steering bogie is designed to for yaw control of the wheel-sets to align the wheels with the track direction during curve negotiation. Existing control laws for active steering are developed by assuming new wheels and rails, and known vehicle and track layout, but do not include the vehicle speed as an input variable. As wheels wear and vehicle speed varies, such static control law may not be optimal. In this paper, the time-varying cant surplus/ deficiency information are adapted into a modified active steering control law. Multi-body simulation results show reduced wheel wear, and increase in passenger comfort, operating speed and wheel life due to the proposed adaptive steering control law.

Active steering bogie using a front view camera on railway vehicle

Active steering bogie using a front view camera on railway vehicle

Active steering bogie using a camera mounted on railway vehicle

Active steering bogie using a camera mounted on railway vehicle

Steering Performance Evaluation of Active Steering Bogie to Reduce Wheel Wear on Test Line

When a railway vehicle runs on a curved section, wear of wheels and rails occur. This is due to the attack angle of the wheel on the rails that occurs because the steering function of the bogie is insufficient. To overcome these problems, we developed an active steering bogie equipped with an electro-mechanical type of active steering system. The prototype of active steering bogie was manufactured and installed on a test train that operated in sections with many curved sections. Steering performance tests for the test train were carried out on commercial line as the test line. As a result of the test, the performance of curvature radius estimation of the active steering bogie showed a very good performance, with only 2.4% error compared with the track design value. The performance of steering angle implementation of the passive bogie running on the curved section is very poor, but that of the active steering bogie is very good. And the lateral force of the wheel, which is directly related to the wheel wear when running on the curved section, showed a maximum 88.1% reduction of the lateral force. Therefore, considering the test results of the active steering bogie in the test line, the steering performance of the active steering bogie developed for reducing the wheel and rail wear is evaluated to be very good. And the wear of wheel measured after test run was 0.54 mm flange wear in passive bogie, but flange wear was not occurred in active steering bogie.

Curving simulation of active steering bogie using traction force

Curving simulation of active steering bogie using traction force

Stability and safety analysis of an active steering bogie according to EN 14363 standard

The angle of attack of a wheelset in a curve is a critical parameter in running safety and curving performance of a railway vehicle. Running with a large angle of attack (AOA) will intensify wear, noise and risk of derailment and, therefore, reduction of AOA is essential to prevent the undesirable consequences. In this regard, passive and active methods are used to control the lateral movements of rail vehicles. In this research, the performance of a new trainset including five wagons with single active steering wheelset bogies, named S5D95, is investigated through dynamic modeling. The simulations were carried out by means of SIMPACK software and then the obtained results were evaluated according to EN14363 standard. The analyses revealed that the lateral forces, derailment coefficients of the wheel and lateral accelerations of the wagons improved significantly by considering steerable mechanism. Owing to its structural merits, it was observed that the active steering bogie runs with higher safety and ride quality in comparison with conventional bogie.

Analysis of the active control of steering bogies for the dynamic characteristics on real track conditions

In this study, an active steering bogie with a re-designed primary axial rubber spring for urban trains was developed. The applied axial rubber spring had a reasonable stiffness that can be achieved in the X, Y and Z directions. Therefore, the steering performance of the bogie can improve because of the lower longitudinal stiffness. The running performance of an active steering vehicle on a curved track was simulated by means of a co-simulation with VI-Rail and MATLAB/Simulink. Further, a control algorithm was developed and applied to an actual active steering bogie. The radius of curvature acquired from the actual active steering bogie by the control algorithm was in reasonable agreement with that acquired from a track inspection vehicle. The numerical analysis revealed a significant improvement in the vehicle safety and ride quality and a reduction in the wheel–rail wear and noise. As a result, the validities of the developed primary suspension and control algorithm of the active steering bogie were confirmed. Further, this study may enable railway vehicles to run more stably and faster on sharp curves.

Study of the active radial steering of a railway vehicle using the curvature measuring method

This study assesses the capability of an active steering bogie to run effectively on a curved track. It presents a curvature measuring method that can be implemented in a railway vehicle system to steer a railway vehicle. This method was used to conduct a field test. The angle of attack and lateral force were reduced in a railway vehicle model on a curved track and analyzed. An active steering system was implemented to improve certain states when a railway vehicle runs on this track, such as wear and derailment index. The railway vehicle was also equipped with an active steering bogie to limit lateral contact forces and wear rates between the wheel and the rail. Finally, this paper describes the modeling of this active steering system and of a system to control the performance of a vehicle as it curves. Simulation results with this bogie were better than those obtained with a conventional railway vehicle, including in terms of lateral forces and the wear number of the wheels. Therefore, the proposed model is more effective than conventional systems with respect to operation on a curved track.

철도관련 사업에서의 환경편익 고려방안

Environmental impact is getting more attention in many feasibility studies for railroad-related projects and research items. For sustainable growth and green transportation, the benefits typically used for feasibility studies in railway-related projects, are composed mostly of economic criterions which is not considering growing attention on changing paradigm. Based on the analysis of current methodologies, improvements in estimating environmental impact especially on noise and pollution are suggested. Active steering bogie has been proposed to satisfy stabilizing and steering performance of railroad. This paper describes the feasibility study of the active steering bogie for a urban railway vehicle based on environment-related criteria.

Instability Analysis in Curve Noise of Urban Railway Systems for Optimal Steering Bogie Development

This paper is primarily aimed at investigating the excitation related factors of curve noise in urban metro lines. This study is initiated within the scope of a project on the development of an active steering bogie, which has the purpose of reducing the wear and noise caused by curves. Noise and wheel profile monitoring tests were carried out four times in 2007–2008. In order to identify the excitation conditions, the frequencies are investigated which are related to the unstable dynamic behaviors of the wheel. In addition, the curve negotiation performance of a metro train was analyzed to investigate the time-domain characteristics of the creepages and creep forces caused by the curved sections. The frequency region, where the flexible dynamic behavior of a wheel is unstable and the occurrence time of the unstable dynamical behavior match well with the results of the noise measurements. The relationship between the noise generation related factors due to the lateral creepage in the contact region and the longitudinal creepage, the spin creepage could be also identified. As a new approach, the parameters related to the curve noise excitation caused by the dynamic instability of the wheel are predicted with consideration to the control concept of the active steering bogie, which is now in development. A calculation on the steering performance of an active steering bogie concept shows a promising reduction in and a stable dynamic condition of the lateral creep parameters of the inner front wheel.

Simulation of active steering control for curving under traction in hauling locomotives

Active steering control in the form of secondary yaw control (SYC) and actuated wheelset yaw (AWY) have been in prototype development. This paper presents a new active steering bogie design, actuated yaw force steering (AY-FS), that is able to steer under high traction loads in tight curves. The AY-FS bogie design is compared with the AWY design. The steering performance AWY under high traction loads has not been previously reported. This paper examines five control methods, three for AWY and two for AY-FS bogies and assesses the traction curving and stability control performance of the alternative designs and control methods compared with each other and to passive steering bogie designs. The curving performance results showed considerable advantage in the proposed AY-FS bogies over the AWY. It was shown that control must be applied to both the yaw angle and the steering angle of the bogie to achieve the best traction steering performance which was not possible with the AWY bogies. The proposed new bogie designs of AY-FS overall give better traction curving and stability performance than the AWY designs.

Design and analysis of an active steering bogie for urban trains

The conventional railway vehicle was designed to ensure running stability using high stiffness elements for primary suspensions. Curving performance of the railway vehicle is relatively low because the natural steering motion of a wheelset is constrained by the high stiffness suspensions. High running stability has always been in conflict with good curving performance in conventional design processes. This conflict problem can be solved with an active steering bogie since active elements properly control the wheelset motions according to track conditions such as straight or curved lines. In this paper, an active steering mechanism for railway vehicle is introduced, and the curving performance of the proposed active steering bogie is investigated through simulation and experiments. According to the results, the proposed active steering bogie is highly effective for curve negotiation.

Curving performance evaluation for active-bogie-steering bogie with multibody dynamics simulation and experiment on test stand

The authors propose a new concept of the active steering bogie, which has simple mechanism and high curving performance. Active-bogie-steering bogie has the steering mechanism only between car-body and bogie frame and no mechanism in wheelsets. On curved track, the bogie frames are steered towards radial steering direction by actuators according to active control law. In this paper, we show that the lateral contact force of the leading-outside wheel can be reduced to zero even on very sharp curve by this mechanism. Validity tests were carried out by using a full-size test bogie on the rolling test stand, which can simulate curve-running condition. Bogie parameters and steering actuator characteristics are identified in order to compare the experimental results with multibody dynamics simulation. After these stand tests and simulation, we successfully verified the effectiveness of the proposed bogie mechanism and control.

Parametric simulation study of traction curving of three axle steering bogie designs

The development of self-steering bogies in locomotives has occurred without extensive study of traction curving bogie dynamics. It is reported that these bogies are unable to steer at high tractive effort levels with the performance essentially the same as rigid bogies. This is due to the required adhesion level approaching wheel rail friction limits and causing creep saturation. Reassessment of the curve steering task in a hauling locomotive has identified that existing concepts of perfect steering [R.M. Goodall and T.X. Mei, Chapter 11: Active suspensions, in Handbook of Railway Vehicle Dynamics, S. Iwnicki, ed., Taylor & Francis Group, Boca Raton, FL, USA, 2006], [R.M. Goodall, S. Bruni, and T.X. Mei, Concepts and prospects for actively-controlled railway running gear, Vehicle Syst. Dynam. 44, supplement 1 (2006), pp. 60–70] are not appropriate for high traction loads in hauling locomotives. An extensive parametric simulation study has been conducted on steering bogie designs for hauling locomotives. Testing of passive steering bogie designs have shown superior performance from forced steering bogies where steering is only partially dependant on wheel rail creep forces. New active steering bogie designs have been proposed [S. Simson, Railway bogie, Australian Provisional Patent Application No. 2007900891, 2007] where steering control is independent of wheel rail creep forces. The new designs combine force steering of wheelsets with secondary yaw activation. The parametric study shows that new active steering bogie designs give superior steering performance under traction.