RT Journal Article T1 On the nonlinear hunting stability of a high-speed train bogie A1 Bustos Caballero, Alejandro A1 Tomas-Rodriguez, Maria A1 Rubio Alonso, Higinio A1 Castejón Sisamón, Cristina AB The hunting phenomenon is an intrinsic swaying motion appearing in railway vehicles due to the vehicle's forward speed and the wheel-rail contact forces. Hunting motion consists of wheelset and other vehicle's components oscillations that arise above a certain vehicle's speed known as critical or hunting speed. These oscillations are of unstable nature and represent a safety hazard as they could lead to the vehicle's derailment. This article analyses the stability of a bogie nonlinear model for a Spanish high-speed train when this is travelling at speeds near the hunting speed. The vehicle's stability is studied by means of root loci methods, and the value of the critical speed is found. In addition to this, the behaviour of the vehicle is studied in both stable and unstable regions and the existence of limit cycles is discussed in this work. Finally, a sensitivity analysis of the axle load and suspension parameters is performed. The results show that the axle load, the vertical stiffness of the primary suspension and the lateral damping of the secondary suspension have a significant influence on the value of the critical speed. PB Springer SN 0924-090X YR 2023 FD 2023-02 LK https://hdl.handle.net/10016/37334 UL https://hdl.handle.net/10016/37334 LA eng NO The research work described in this paper is part of the R&D and Innovation projects MC4.0 PID2020-116984RB-C21 and MC4.0 PID2020-116984RB-C22 supported by the MCIN/AEI/10.13039/501100011033 and by the Universidad Carlos III de Madrid through the "Ayudas para la movilidad de investigadores de la UC3M en centros de investigación nacionales y extranjeros en sus dos modalidades 2019" project. DS e-Archivo RD 18 jul. 2024