A framework for dynamic modelling of railway track switches considering the switch blades, actuators and control systems

Abstract

The main contribution of this paper is the development and demonstration of a novel methodology that can be followed to develop a simulation twin of a railway track switch system to test the functionality in a digital environment. This is important because, globally, railway track switches are used to allow trains to change routes; they are a key part of all railway networks. However, because track switches are single points of failure and safety-critical, their inability to operate correctly can cause significant delays and concomitant costs. In order to better understand the dynamic behaviour of switches during operation, this paper has developed a full simulation twin of a complete track switch system. The approach fuses finite element for the rail bending and motion, with physics-based models of the electromechanical actuator system and the control system. Hence, it provides researchers and engineers the opportunity to explore and understand the design space around the dynamic operation of new switches and switch machines before they are built. This is useful for looking at the modification or monitoring of existing switches, and it becomes even more important when new switch concepts are being considered and evaluated. The simulation is capable of running in real time or faster meaning designs can be iterated and checked interactively. The paper describes the modelling approach, demonstrates the methodology by developing the system model for a novel “REPOINT” switch system, and evaluates the system level performance against the dynamic performance requirements for the switch. In the context of that case study, it is found that the proposed new actuation system as designed can meet (and exceed) the system performance requirements, and that the fault tolerance built into the actuation ensures continued operation after a single actuator failure.

Keywords

Railway track switch / Mathematical modelling / Redundant actuation / Finite element analysis

References

[1.] Bemment SD, Goodall RM, Dixon R. Improving the reliability and availability of railway track switching by analysing historical failure data and introducing functionally redundant subsystems. Proc Inst Mech Eng F: J Rail Rapid Transit, 2017, 232(5): 1407-1424,

[2.] Rama D, Andrews JD. A reliability analysis of railway switches. Proc Inst Mech Engt F: J Rail Rapid Transit, 2013, 227(4): 344-363,

[3.] Marquez FPG, Weston P, Roberts C. Failure analysis and diagnostics for railway trackside equipment. Eng Fail Anal, 2007, 14(8): 1411-1426,

[4.] Hamadache M, Dutta S, Olaby O, et al.. On the fault detection and diagnosis of railway switch and crossing systems: an overview. Appl Sci, 2019, 9(23): 5129,

[5.] Cao Y, Sun Y, Xie G et al (2021) A sound-based fault diagnosis method for railway point machines based on two-stage feature selection strategy and ensemble classifier. IEEE Trans Intell Transp Syst 23(8):12074–12083

[6.] Hu X, Cao Y, Sun Y, Tang T (2021) Railway automatic switch stationary contacts wear detection under few-shot occasions. IEEE Trans Intell Transp Syst 23(9):14893–14907

[7.] S-Code. http://www.s-code.info/. Accessed 1 May 2023

[8.] WIRAS. http://www.winterproofturnout.info/. Accessed 1 May 2023

[9.] Bemment SD, Ebinger E, Goodall RM, et al.. Rethinking rail track switches for fault tolerance and enhanced performance. Proc Inst Mech Eng F J Rail Rapid Transit, 2017, 231(9): 1048-1065,

[10.] Olaby O, Dutta S, Harrison T, et al.. Realisation of a novel functionally redundant actuation system for a railway track-switch. Appl Sci, 2021, 11(2): 702,

[11.] Farhat N, Ward CP, Goodall RM, et al.. The benefits of mechatronically-guided railway vehicles: a multi-body physics simulation study. Mechatronics, 2018, 51: 115-126,

[12.] Magalhaes H, Marques F, Antunes P et al (2022) Wheel-rail contact models in the presence of switches and crossings. Vehicle Syst Dyn 61(3):838–870

[13.] Bezin Y, Pålsson BA (2021) Multibody simulation benchmark for dynamic vehicle-track interaction in switches and crossings: modelling description and simulation tasks. Vehicle Syst Dyn 61(3):644–659

[14.] Bezin Y, Sarmiento-Carnevali M, Sichani MS et al (2019) Dynamic analysis and performance of a repoint track switch. Vehicle Syst Dyn 58(6):843–863

[15.] Shih JY, Ambur R, Boghani H, et al.. A new switch and crossing design: introducing the back to back bistable switch. J Civil Eng Constr, 2020, 9(4): 175-186,

[16.] Shih JY, Weston P, Entezami M. Dynamic characteristics of a switch and crossing on the West Coast main line in the UK. Railw Eng Sci, 2022, 30(2): 183-203,

[17.] Dutta S, Harrison T, Ward CP, et al.. A new approach to railway track switch actuation: dynamic simulation and control of a self-adjusting switch. Proc Inst Mech Eng F: J Rail d Rapid Transit, 2020, 234(7): 779-790,

[18.] Li L, Dutta S, Dixon R, Stewart E et al (2022) Railway track switch simulation: a new dynamic model for studying actuator and switch blade dynamics. Proc Inst Mech Eng F J Rail Rapid Transit 237(6):775–783

[19.] Rao SS (2021) Mechanical Vibrations (SI edition). Pearson Prentice Hall, Singapore

[20.] Panzer H, Hubele J, Eid R et al (2009) Generating a parametric finite element model of a 3d cantilever timoshenko beam using matlab. Lehrstuhl für Regelungstechnik, Erlangen

[21.] BEMMENT S, Goodall R, Ebinger E et al (2015) Extending maintenance intervals of track switches utilising multi-channel redundancy of actuation and sensing (infrastructure). In: The Proceedings of International Symposium on Seed-up and Service Technology for Railway and Maglev Systems: STECH, Chiba, pp 2E14–1

[22.] Bemment SD, Dixon R, Goodall RM (2016) Railway points, railway points operating apparatus and railway track crossing. US Patent 10260202

[23.] Ferreira AJ. . MATLAB codes for finite element analysis, 2009 New York Springer

[24.] Ling X, Haldar A. Element level system identification with unknown input with Rayleigh damping. J Eng Mech, 2004, 130(8): 877-885,

[25.] Mohammad D, Khan N, Ramamurti V. On the role of Rayleigh damping. J Sound Vib, 1995, 185(2): 207-218,

[26.] Li Y, Ang KH, Chong GC. PID control system analysis and design. IEEE Control Syst Mag, 2006, 26(1): 32-41,

[27.] Garcia-Sanz M. The Nyquist stability criterion in the Nichols chart. Int J Robust Nonlinear Control, 2016, 26(12): 2643-2651,

Funding

Horizon 2020(826255)