Effects of Magnetorheological Bushings on Yaw Dynamics of Automobiles

Yaw control systems have been studied in the automotive industry in order to increase the handling and stability of vehicles. This thesis proposes achieving yaw control by the use of magnetorheological (MR) bushings in the front and rear wheels in a manner that would provide for a controlled way for the passively generated lateral forces to deflect the toe angle of the wheels for minor adjustment in the steering angle at the front and at the rear. This system paired with a reference model approach utilizing a simple control ideology creates an understeer affect and can be used to increase handling performance without compromising stability. Although steering and wheel torque control are more aggressive methods for achieving yaw control, this thesis shows that MR bushings should be considered in addition to traditional methods. These MR bushings will be tested in various conditions to prove that they are indeed advantageous for vehicle handling.