The Analysis of the Stiffness-Damping Parameters of a H-Bahn Vehicle 2017-01-1890

H-Bahn ("hanging railway") refers to the suspended, unmanned urban railway transportation system. Through the reasonable platform layout, H-Bahn can be easily integrated into the existing urban transit system. With the development of urban roads, the associated rail facilities can be conveniently disassembled, moved and expanded. The track beam, circuits, communication equipment, and sound insulation screen are all installed in a box-type track beam so that the system can achieve a high level of integration and intelligence. The carriage of the modern H-banh vehicle is connected with the bogies by two hanging devices. The vehicle is always running in the box-type track beam; therefore there are less possibilities of derailment. Consequently, the key work focuses on the running stability evaluation and curve negotiation performance analysis. In order to study the factors affecting running stability, the different stiffness and damping parameters in the primary and secondary suspension system are assigned to calculate the running stability index. To begin with, the vertical and lateral mathematic -dynamics models of the vehicle are established. Moreover, based on the USA VI rail spectrum, the vertical and lateral input displacements of the rail can be developed. In addition, the time-domain acceleration responses calculated by the dynamics model are converted to the amplitude-frequency characteristic curves by the Fourier transform. Finally, the weighted Sperling index calculated by the corresponding frequency and amplitude can evaluate the vehicle running stability. From the results of the vertical running stability analysis, the vertical indexes W_z are less than 2.5 almost, so that the running stability belongs to Level 1. For analyzing the lateral vibration, the hanging device is regarded as a fixed rigid body connecting the vehicle body and bogies. From the results of lateral running stability analysis, the lateral index W_y increases with the lateral stiffness of the air spring (< 2.5 × 10⁵), and W_y is more than 3.0 at some points. In order to analyze the curve negotiation performance, the statics model describing the lateral rolling condition is established. By solving the nonlinear equations describing the statics model, the rolling angles of vehicle body are calculated in different conditions. The stiffness of air spring and centrifugal acceleration should be controlled in the limited values for improving the curve negotiation performance.