Multi-level torque distribution strategy for four-wheel drive articulated vehicles based on slip rate control

Abstract Under specific working conditions such as low-speed high-torque operation and starting on a half slope with heavy loads, four-wheel drive articulated vehicles are easy to wheel slipping, which reduces the operation efficiency. To solve this problem, a multi-level torque distribution strategy based on slip rate control is proposed. Firstly, based on the theories of vehicle kinematics and dynamics, a complete vehicle model of the distributed wheel-side driven articulated vehicle is established, and the vehicle dynamics equations are obtained. Secondly, a wheel model is established to calculate the slip rate of each wheel. On this basis, a slip rate controller based on GA-PID (Genetic Algorithm-Proportional-Integral-Derivative) is designed. The optimal control parameters of the PID are obtained through the iteration of the genetic algorithm, and the torque control quantity is obtained. Finally, a multi-level torque distribution strategy is designed to enable the vehicle to obtain the optimal driving performance. To verify the effectiveness of the proposed strategy, tests were conducted for the low-speed high-torque working condition. The results demonstrate that this strategy significantly reduces the wheel slipping situation and effectively improves the work efficiency.