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The method currently used for the estimation of train resistance based on specific train resistance has some shortcomings. This method is applied by various railway infrastructure managers, e.g. in the Czech Republic. In this article, first, the Czech formulae for the calculation of train resistance of freight trains are introduced and compared with selected foreign methods. Operational experience from recent years shows that the train resistance formulae used are too conservative and do not correspond to the state-of-the-art railway technology. Therefore, a modified approach for the estimation of train resistance is proposed in this paper. The modification is based on an analysis of run-down tests conducted with ordinary container trains currently operating on the Central European railway network. The contributing factors in the proposed train resistance formula are discussed.

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Many publications show that the ride comfort of a railway vehicle can be significantly improved using a semi-active damping control of the lateral secondary dampers. However, the control efficiency depends on the selection of the control algorithm and the damper dynamic behaviour, i.e., its force rise response time, force drop response time and force dynamic range. This paper examines the influence of these parameters of a magnetorheological (MR) damper on the efficiency of S/A control for several control algorithms. One new algorithm has been designed. Hardware-in-the-loop simulation with a real magnetorheological damper has been used to get close to reality. A key finding of this paper is that the highest efficiency of algorithms is not achieved with a minimal damper response time. Furthermore, the force drop response time has been more important than the force rise response time. The Acceleration Driven Damper Linear (ADD-L) algorithm achieves the highest efficiency. A reduction in vibration of 34% was achieved.