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Future high speed trains are the main focus of the DLR research project Next Generation Train (NGT). One central point of the research activities is the development of a mechatronic track guidance for the two axle intermediate wagons with steerable, individually powered, independently rotating wheels. The traction motors hereby fulfil two functions; they concurrently are traction drives and steering actuators. In this paper, the influence of the track properties-line layout and track irregularities-on the performance requirements for the guidance actuator is investigated using multi-body-models in SIMPACK®. In order to compromise on the design conflict between low wheel wear and low steering torques, the control parameters of the mechatronic track guidance are optimized using the DLR in-house software MOPS. Besides of the track irregularities especially the increasing inclination at transition curves defines high actuator requirements due to gyroscopic effects at high speed. After introducing a limiter for the actuating variables into the control system a good performance is achieved.

The formulation of the wheel-rail contact is a crucial issue in simulations considering the running dynamics of railway vehicles. Therefore a modeling environment that is dedicated to railway vehicle dynamics such as the new DLR RaiwayDynamics Library relies on an efficient representation of the kinematics and forces or torques, respectively, that appear at the wheel-rail interface. A number of different formulations have been developed since the underlying rolling contact problem was firstly discussed in literature in 1876. The paper overviews these wheel-rail contact formulations and then presents the implemented variants in detail. The DLR RailwayDynamics Library is used to model and simulate the behavior of an experimental scaled M 1:5 running gear operating on the DLR roller rig. The simulations results are compared and validated with measurements.

The DLR research project Next Generation Train deals with concepts, methods and technologies for a very high-speed train in double deck configuration and light-weight design. Due to these three key features crosswind stability is a particular subject of study. It is shown that conventional approaches here fall short of guaranteeing safety in high-wind occurrences according to the given homologation standards. Therefore this paper discusses the feasibility of different approaches to ensure crosswind stability by means of active control. Four different concepts are overviewed, the most promising one is then chosen und examined in detailed multibody simulations that are based on data from wind tunnel measurements of the Next Generation Train.

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