Vehicle dynamics improvement using developed robust controller

In this paper, robust control and improvement of vehicle dynamic and stability is considered. Direct yaw control as a means of corrective moment generating could be effective during vehicle maneuvers. Due to the differential brake forces, a corrective moment is generated at the center of gravity of vehicle to be effective in an emergency diversion and loss of the stability conditions. The control system is designed to produce the corrective torque required in top-level and the brake torque of each wheel in low-level controller. The corrective moment is designed by developed quantitative feedback theory as a robust controller method. This robust controller considers the vehicle system uncertainties existed by change of center of gravity, road conditions, tire inflation pressure and many reasons. The uncertainties firstly considered by a statistical method named Taguch to find the most effective parameters in the model. Base of the linear model derived from nonlinear vehicle dynamics, all the uncertainties studied by a pre-filter and compensator control and then applied in comprehensive nonlinear model. Moreover, the brake torque is generated by a set of simple rules. A double lane change maneuver with the low friction road is employed to show the robust performance of the controller.