Active Front Steering Controller Design for Electric Vehicle System by Using Disturbance Observer Method

The purpose of the paper is to propose a new control scheme in active front steering (AFS) for vehicle stability using disturbance observer method. In the paper, the ideal yaw rate can be calculated on the linear two-degrees-of-freedom vehicle model. In addition, the actual sideslip angle can also be estimated by using a state observer. Based on this, two kinds of baseline AFS controllers are proposed by using PID and terminal sliding mode (TSM) techniques such that the actual yaw rate will approach the reference value. To further improve the performance of the closed-loop system, by using the disturbance observer (DOB) technique, the corresponding composite control schemes are also been given in the presence of uncertainties and external disturbances. The results show the effectiveness of the proposed AFS control schemes via simulation of Carsim software under single lane change procedure. It has been verified that by using disturbance observer method the two composite controllers are shown to be more effective than the baseline controllers.