KINEMATIC STEERING CONTROL OF RAIL VEHICLES.

Rail vehicles with forced-steering trucks employ passive linkages between the wheel sets and car body that sense track curvature and steer the wheel sets accordingly. The linkage dimensions, which are related to a steering gain, are typically selected to align kinematically the wheel sets radially. This paper addresses the effect of the steering gain on the curving performance of a forced-steered truck operating at balance speed. The results show that the steering gain corresponding to kinematic radial alignment, called the pure rolling line steering gain, understeers the wheel sets during moderate and tight curve negotiation. For these curving conditions, steering gains slightly larger than the pure rolling line gain offer improved curving performance in terms of decreased wheel set misalignments.