Stability Control of Steer-by-Wire Vehicle Based on Super-Twisting Sliding Mode Control Algorithm

A control strategy combining the novel variable steering ratio (NVSR) and yaw moment control is proposed to address the stability issues in steer-by-wire (SBW) vehicles. The NVSR is designed based on variable yaw rate gains and incorporates a convolution smoothing algorithm. This ensures that the system meets the response requirements of SBW vehicles at low speeds, while satisfying their stability requirements at high-speeds. Secondly, precise control of the yaw torque is achieved by implementing the super-twisting sliding mode control (STSMC) algorithm. Finally, co-simulation experiments are carried out using Carsim–Simulink. These experiments demonstrate that the designed NVSR provides low-speed maneuverability and high-speed stability in vehicle steering, and that the PID effectively tracks the wheel steering angle. Additionally, the STSMC ensures the vehicle’s stability and safety.