The research of effects of suspension bushing stiffness on vehicle yaw response performance

With mathematical model of a double track vehicle the mechanism for which suspension bushing stiffness affects on vehicle steady-state yaw response behavior is explained. A vehicle model including front McPherson suspension, rear multilink suspension, power transmission system, steering system, tires and body etc. is built by ADAMS/CAR. With the ADAMS/CAR vehicle model, influence of lateral and longitudinal force exerted at tires on steering angle change of the front and rear axles are analyzed, and effects of rubber bushing stiffness at suspension link pivots on vehicle yaw response are calculated. It is found that the stiffness change of rubber bush in axial and torsional direction at the front and rear suspension pivots have little influence on the wheel steer angle, but those stiffness change in radial direction of rubber bushing of both front and rear of the front suspension pivots affect yaw response of the vehicle, especially the change of bushing radial stiffness of three lateral control arms of the rear suspension produce important influence to the vehicle yaw response performance.