Improving the Dynamic Performance of Passenger Cars via Rear Suspension Mechanism Modification

This paper presents the results of a recent project of IKCo’s research center to modify Paykan 1600’s rear suspension mechanism with the purpose of improving comfort, stability and handling qualities. The car was originally equipped with a solid rear axle with leaf springs. By replacing the original mechanism with a three-link mechanism with panhard bar and coil springs, the ride comfort and handling characteristics of the car were noticeably improved. 7DOF ride and 3DOF handling models were developed and analyzed to determine the important kinematic and dynamic effects of the new mechanism such as Roll Center and Roll Stiffness on vehicle responses. To verify analytical results, subjective tests were carried out on the vehicle. The results demonstrated remarkable improvement of the car’s dynamic behavior.