Abstract: Typically, traditional vehicle ABS strategy only focuses on maximizing longitudinal braking force, which makes it difficult to take into account the lateral force of the tire at the same time, thus making it difficult to ensure vehicle lateral stability during the ABS process. The multi-tire composition of the intelligent semi-trailer vehicle can independently adjust the longitudinal and lateral braking forces of the wheel group, providing conditions for further improving its lateral stability. Based on the architecture of independently controlled braking systems for each wheel, a braking ABS strategy with coupled reconstruction of braking force fluctuations within wheel group is proposed. The upper-level controller first judges the road adhesion condition through the road recognition algorithm to obtain the optimal slip rate of the current road surface, and then obtains the target slip rate through the formulated braking rule. The lower-level controller independently controls the braking of each wheel to achieve asynchronous braking within the wheel group. Finally, experimental validation was conducted through Simulink-TruckSim co-simulation and hardware-in-the-loop testing platform. The results show that compared with the conventional ABS control strategy, the anti-lock strategy can maintain large lateral force during the braking process, reducing the yaw angular velocity range of tractor and semi-trailers by 25.1% and 11.2%, the center of gravity lateral angle by 15.2% and 25.6%, the lateral acceleration by 29.8% and 33.2%, These results confirm the effectiveness of the proposed ABS strategy in enhancing lateral stability during emergency braking for semi-trailer trucks.

Key words: fully distributed braking system, anti-lock braking control strategy, multi-axle semi-trailer, parameter estimation, slip rate control