Torque vectoring for rear axle using Adaptive Sliding Mode Control

Active chassis control systems have been developed and applied increasingly in the automotive industry to improve vehicle global safety and comfort from normal to critical driving situations. These systems like Electronic Stability Program (ESP), Vehicle Dynamic Control (VDC), Direct Yaw moment Control (DYC), Traction Control System (TCS) play the most important role therein but they are all braked based systems. The weakness of these s is to cause energy loss during acceleration, whereas Torque Vectoring System could improve the driving stability without deceleration during cornering or acceleration. An additionally corrective torque based on desired yaw moment is computed from reference yaw rate and sideslip angle and then applied to the left and the right rear wheels. In this paper, a Torque Vectoring Controller on the basis of an Adaptive Sliding Mode Control (SMC) in which a combined sliding surface derived from the error of actual and reference signals of both yaw rate and body sideslip angle and an adaptive gain control law are proposed. The proposed approach is verified by the co-simulations of Matlab®/Simulink® and Carsim®. Simulation results demonstrate the effectiveness of the system and the overall enhancement in vehicle's stability and drivability.