Road Sense Construction for Steer-by-Wire System Based on Switching Explicit Model Predictive Control With Friction and Vibration Compensation

Replacing traditional mechanical linkages, the steer-by-wire (SbW) system represents a pivotal advancement in automotive steering technology. However, the decoupled design inherently blocks the transmission of road sense to the hand wheel and compromises active return performance. To ensure the provision of necessary road sense for drivers while enhancing active return performance, this article proposes a dual-target road sense construction that integrates steering feedback torque (SFT) and return angular speed (RAS). Then a switching controller based on explicit model predictive control (EMPC) is designed to achieve dual-target control. The controller employs a dynamic switching logic based on hand wheel angle and torque thresholds to ensure switching accuracy between SFT and RAS tracking. By analyzing the mechanical characteristics of the hand wheel module, a hybrid disturbance compensation model is proposed. In addition to friction compensation, a vibration model is introduced to suppress torque ripple caused by the worm gear reducer, improving tracking accuracy and enhancing the driver’s steering feel. Finally, the sinusoidal steering experiments show a reduction of 44.5%, 91.7%, and 45.9% at 0 km/h and 60.8%, 84.7%, and 19.5% at 60 km/h in SFT tracking error compared to PID, uncompensated EMPC and friction compensated EMPC, respectively. The active return tests validated that the dual-target road sense construction could reduce insufficient return at low speeds and overshooting at high speeds, while maintaining essential road sense.