Path Following Strategy for Multi-Axle Vehicles via Nash Game-Based Coordinated Control of AFS and DYC

Due to their complex structure and large inertia, multi-axle hub electric drive vehicles often suffer from response delays and insufficient control sensitivity. To improve path tracking accuracy and handling stability under high-speed and low-adhesion conditions, this paper proposes a coordinated control strategy that integrates a three-dimensional stability assessment with a Nash game-based approach for active front steering (AFS) and direct yaw moment control (DYC) systems. A path tracking control model tailored for multi-axle vehicles is developed, and a robust Tubular Model Predictive Control (Tube-MPC) method is employed to enhance trajectory tracking performance under model uncertainties and external disturbances. Within the prediction horizon of Tube-MPC, the system continuously evaluates whether the vehicle state remains within the stable region. If the state exceeds this region, a Nash game-based coordination mechanism is activated to formulate a multi-objective control game between AFS and DYC, achieving equilibrium in control allocation and optimizing system performance. To address handling challenges at high speeds, longitudinal deceleration is introduced as an auxiliary control strategy in the game-theoretic coordination framework. This allows the system to dynamically switch between AFS+DYC and deceleration strategies to balance stability and performance under multi-objective control goals. Finally, simulations conducted on a co-simulation platform using MATLAB/Simulink and TruckSim under typical double lane change scenarios demonstrate that the proposed strategy significantly improves path tracking accuracy and handling stability of multi-axle vehicles under extreme conditions such as high speeds and low adhesion.