Study on the effect of semi-active control for equivalent conicity

To improve ride comfort on train journeys, it is important to reduce the amplitude of lateral vibration acceleration. As a method for such a purpose, semi-active suspension has been proposed and substantially used. On the other hand, the longer distance of the train runs, the more severe wears are evident on wheel treads; an equivalent conicity becomes larger, which adversely affect the characteristics of vehicle dynamics. It is hence expected to improve ride comfort under vibrations by adequate semi-active control without depending on the equivalent conicity. A study under this research with a simulation model was made to the effect of the semi-active control for the equivalent conicity. We could verify that as the equivalent conicity becomes larger caused by longer distance of a train runs, the lateral relativity velocity between a car body and a bogie became smaller; a damping ratio by semi-active damper became smaller. As the result, it is conceivable that an impact accordingly decreases with the semi-active control.