Output Feedback-Based Direct Yaw Control System and Finite-Time Robust Dynamic Control Allocation for Unknown Road Conditions

This paper presents a three-layer control architecture designed to enhance vehicle lateral stability under uncertain and varying road conditions. The system utilizes output-feedback-based finite-time controllers to track the desired yaw rate and longitudinal slip in the upper and lower layers, respectively. The middle layer incorporates a finite-time robust dynamic control allocation to distribute longitudinal slips among the tires. This approach effectively handles uncertainties and changing road conditions without the need for direct estimation of unmeasurable variables such as tire-road friction and sideslip angle. The proposed output feedback control law consists of a stabilizer component to ensure finite-time stability, a compensator to eliminate the unknown function in the upper and lower layers, and an auxiliary tracking term. Key advantages of the proposed framework include: no requirement for additional sensors, finite-time convergence, reduced computational complexity compared to optimization-based methods, and the ability to perform finite-time stability analysis for the integrated closed-loop system. The system performance is evaluated using a validated 10-degree-of-freedom vehicle dynamics model and CarSim simulations during a double-lane change maneuver. Simulation results demonstrate the superiority of the proposed control structure over sliding mode control, offering improved tracking accuracy and robust performance under varying road conditions.