Abstract:
According to the independent and controllable advantage of the torque of each wheel for four-wheel independent driving electric off-road vehicle, to improve the traction and off-road ability of off-road vehicle, a coordinated control strategy of driving torque was proposed. The torque of the driving motor was pre-distributed according to the load of each axis. The optimal estimation of road slip rate was realized by the extreme value searching algorithm based on wheel slip rate and road adhesion coefficient. Proportional-integral-differential(PID)control-sliding mode control(SMC)and state-based driving force redistribution method were used to achieve the coordinated distribution of wheel drive torque for restraining the wheelslip under bad road conditions. Through the co-simulation of CarSim/MATLAB and hardware-in-the-loop(HIL)test, the experimental verification of climbing steep slope, single adhesion road surface, split road and continuous unrolling road was carried out. The results show that by the proposed control strategy, the torque of the driving wheel can be distributed according to the actual working conditions, and the slip rate of wheels is reduced to realize the optimization of the driving force of whole vehicle.