Coordinated traction control of on-demand four-wheel-drive vehicles under complex start-up situation

The traction control system (TCS) allows for better power performance and stability of the vehicle. On-demand four-wheel-drive (OD4WD) vehicles are expected to start up in complex situations such as only one wheel landing on the high friction road surface. Therefore, the TCS applied in OD4WD vehicles requires coordinated control of the engine, brake, and transfer case. If the controller is not well designed, the performance of the vehicle would decrease and the components may be damaged. Aiming to deal with the traction control problem of OD4WD vehicles, a coordinated controller is proposed in this paper. First, the models of the main components of the OD4WD vehicle are analyzed. Then, the coordinated controller is designed based on the active disturbance rejection controller (ADRC), the fuzzy controller, and the sliding-mode controller. The estimation and calculation methods of the necessary information are also designed. After that, vehicle experiments of the start-up process are carried out in typical situations to validate the effectiveness of the controller. Results show that the coordinated controller ensures power performance and improves the stability of the vehicle.