Anti-slip control for multi-axle distributed-drive special vehicles during ramp driving

To address the demand for enhanced dynamic performance of multi-axle distributed-drive special vehicles in complex terrains, this paper proposes a longitudinal torque coordination control architecture integrating dynamic parameter estimation and multi-objective collaborative optimization. By analyzing the longitudinal dynamic model during ramp driving, a joint gradient resistance estimation module based on Recursive Least Squares (RLS) and Extended Kalman Filter (EKF) is designed to provide critical parameter inputs for the control strategy. Leveraging the independent wheel torque control capability of distributed drive systems and considering wheel load distribution during slope traversal, a tire load rate-based driving torque pre-allocation principle is established. Furthermore, wheel slip phenomena under low-adhesion heterogeneous slope conditions during both driving and starting are analyzed, leading to the development of individual wheel torque control strategies based on slip ratio and angular acceleration. These strategies are integrated with a vehicle-level torque distribution strategy based on tire load rates to achieve secondary optimized torque allocation. Simulation results demonstrate that the proposed control strategy significantly improves dynamic performance and stability while reducing instability risks in extreme operating conditions.