Sideslip angle could provide important information concerning vehicle's stability. Unfortunately direct measurement of sideslip angle requires a complex and expensive experimental set-up, which is not suitable for implementation on ordinary passenger cars; thus, this quantity has to be estimated starting from the measurements of vehicle lateral/longitudinal acceleration, speed, yaw rate and steer angle. According to the proposed methodology, sideslip angle is estimated as a weighted mean of the results provided by a kinematic formulation and those obtained through a state observer based on vehicle single-track model. Kinematical formula is considered reliable for a transient manoeuvre, while the state observer is used in nearly quasi-state condition. The basic idea of the work is to make use of the information provided by the kinematic formulation during a transient manoeuvre to update the single-track model parameters (tires cornering stiffnesses). A fuzzy-logic procedure was implemented to identify steady state or transient conditions

The paper presents an analysis of heavy freight train dynamics carried out both from a numerical and experimental point of view. A numerical procedure has been developed to investigate the dynamics of heavy freight trains; the proposed methodology combines a new numerical model designed for the longitudinal dynamics of the whole trainset called TSDyn (TrainSet Dynamics simulator) with a multi-body code named MoNSTram (Modular Non-Stationary TRAMcar dynamics simulator) originally developed to analyse the dynamics of modular tramcars and used for a more detailed investigation of the response of a trainset segment. On-line tests have been carried out aiming at acquiring data both for the validation of the simulation code and for the characterisation of buffers' response. A numerical analysis is eventually presented to show the effect of trainset composition on running safety

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Appropriate modelling of the dynamic behaviour of the vehicle components, particularly car body flexibility, is essential in the analysis of railway vehicle comfort performance, especially for high-speed vehicles. This paper deals with the description of the adopted approach to set up a complex numerical model of the railway vehicle, suitable for reproducing its dynamic behaviour in the 0-50 Hz frequency range, especially with respect to the ride comfort problem. The implemented model is used to simulate in time domain the dynamic behaviour of a vehicle running on irregular track. Numerical results are validated by means of comparison with experimental data of on-line tests. Finally, the analytical model is used to perform a sensitivity analysis, in order to point out the parameters that most significantly affect comfort

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