Ride comfort improvements in switches using active secondary suspension with preview

Abstract

Trains often have to change their track when entering or leaving a station. This represents a challenging scenario related to passenger ride comfort due to small curve radii in switches. The abrupt change of curvature usually results in a bumpstop contact in the secondary suspension. The paper presents a control strategy with preview information based on stored track data. For this purpose, a calculation method is introduced to determine forces and torques acting on the carbody, e.g. when passing switches in advance. This data can be used by an active lateral secondary suspension in order to prevent bumpstop contact. Corresponding multibody simulations showed promising results. Peak values of lateral acceleration acting on the passengers can be reduced significantly resulting in better ride comfort.