Abstract
In this this work, the bogie pseudo-hunting motion of a reduced-scale model railway vehicle, running on doublecurved rails is theoretically and experimentally investigated. Bogie hunting motion occurs for the real railway vehicles (e.g., bullet trains) during running on straight rails at high travelling speeds (e.g., 200-300 km/h) and long wavelengths (e.g., 20-30 m). Since due to the speed and space limitations, such conditions cannot be duplicated in laboratory, a pseudo-hunting motion was induced by employing convex-concave curvilinear rails. Firstly, the test rig, the system of vibration measurement and ride-comfort evaluation, and the experimental procedure are described. Next, a model to clarify the kinematics of the carriage and bogies, as well as, the stroke of the yaw damper, against the particular geometry of the curvilinear rails, is suggested. Resonant peaks observed on the recorded vibration spectra during the travelling of the vehicle, on straight and double-curved rails, are interpreted based on the natural frequencies of various elastic elements used in the construction of the railway vehicle. Ride-comfort is evaluated according to the ISO 2631 standard, and also by using the specific frequency weightings (filters) that account for the discomfort sensation, during the reading and writing activities.
