Pareto optimization of railway bogie suspension damping to enhance safety and comfort

This paper presents optimization of damping characteristics in the bogie suspension using a multi-objective optimization methodology. The damping is investigated and optimized in terms of the resulting performances of a railway vehicle with respect to safety, comfort and wear considerations. A complete multibody system model describing the railway vehicle dynamics is implemented in commercial software Gensys and used in the optimization. In complementary optimization analyzes, a reduced and linearized model describing the bogie system dynamics is also utilized.Pareto fronts with respect to safety, comfort and wear objectives are obtained, showing the trade-off behavior between the objectives. Such trade-off curves are of importance, especially in design of damping functional components. The results demonstrate that the developed methodology can successfully be used for multi-objective investigations of railway vehicle within models of different levels of complexity. By introducing optimized passive damping elements in the bogie suspensions both safety and comfort are improved. In particular it is noted that the use of optimized passive damping elements can allow for higher train speeds. Finally, adaptive strategies for switching damping parameters with respect to different ride conditions are outlined and discussed