A Study on the Handling Performances of a Large-Sized Bus with the Change of Rear Suspension Geometry

Since the kinematic characteristics of a vehicle suspension are very complex and difficult to understand, CAE techniques must be applied to perform the suspension analysis. In this study, the influences of rear suspension geometry on the handling performances of a large-sized bus are investigated. The bus involved in this study has air spring type rigid axle suspensions with four links. Quasi-static analyses are performed to evaluate the roll characteristics of the front and rear suspension. The quasi-static responses of suspensions are evaluated in terms of roll center height and roll steer. Roll center height is mainly dependent on the vertical displacement of a panhard rod, and the vertical displacements of lower control links affect chiefly the roll steer. The parameter study with the change of rear suspension geometry is conducted to investigate the vehicle handling performance. This parameter study shows that the vertical displacement and orientation of a panhard rod have a significant influence on the handling performance of a large-sized bus.