Second-order sliding mode control of vehicular DYC system

In order to improve the accuracy and robustness of the vehicular direct yaw-moment control (DYC) system, a second-order sliding mode (SOSM) control strategy is proposed. In this strategy, first, the upper controller of DYC, namely the body locomotion controller, is designed based on the higher-order sliding mode theory, which is used to take the advantages of sliding mode control and restrain the inherent flutter, and, the corresponding sliding mode control law is designed based on the spiral control algorithm. Then, the lower controller of DYC, namely the slip controller, is designed based on the automatic objective slip identification and the logic threshold control, which is employed to generate the objective yaw-moment maintaining the vehicle stability. Moreover, a hardware-in-loop/driver-in-loop test platform is built in the environment of Matlab/Simulink and veDYNA, on which the proposed DYC strategy is evaluated. The results show that the proposed control algorithm greatly improves the driving stability of vehicles under extreme conditions and significantly enhances the active safety performance of vehicles.