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The electronic-based recently developed railway vehicles compromising at high speeds by consuming eco-friendly energy and providing better transportation facilities without complicating the car designs. In this study, the achievable performance of the secondary suspension by using a semi-active controller designed with a local-skyhook damping is compared with the active controller that utilizes an H∞control methodology. Besides, to cope up with the coarse track excitations which disrupt the rail holding quality on the rough terrains, a primary controller obliges to deal with the worst-case occurences is considered. The simulation studies attribute to promising results both at the low and mid frequency range by providing improved ride comfort and high passenger safety by using only active primary designs at a price of a typical actively designed secondary suspensions.

In this work, the mathemtical model of a railway passenger car with conventional and radial-elastic wheels is analyzed. Stochastic excitations are applied to the wheelsets. The local elasticity between the wheel and the rail is modelled by a linearized stiffness behaviour due to geometrical effects to simplify the controller design procedure for H2analysis. An optimization of the vertical dynamics is performed by reducing the the H2norms of the dynamic wheel forces while keeping the RMS gain of carbody accelerations at a constant level. It is seen that the controller performs well on the low frequency range where the ride comfort is more pronounced and partially on the high frequency range to suppress the environmental ground vibrations and structure-borne noise.

In this paper, a multi-objective control of a three-degrees-of-freedom cabin model for a commercial truck excited by random road disturbances is studied. The multi-objective control problem is formulated as a non-convex and non-smooth optimization problem with controller order restricted to be less than the vehicle model order. For a range of control orders, controllers are synthesized by using the HIFOO toolbox. The simulation results show that the cabin vibrations are effectively suppressed by this methodology.

This paper presents two procedures for multi-objective control of a full-vehicle suspension excited by random road disturbances. The control problem is first formulated as a mixed H2/H∞synthesis problem and an output feedback solution is obtained by using linear matrix inequalities. Next, the multi-objective control problem is re-formulated as a non-convex and non-smooth optimization problem with controller order restricted to be less than the vehicle model order. For a range of orders, controllers are synthesized by using the HIFOO toolbox. The efficacy of the presented procedures are illustrated by design examples.