Comprehensive Modelling and Robust Control for Steer-by-Wire Vehicles via Sliding Mode Methodologies

Automotive steer-by-wire (SbW) systems are subject to significant challenges arising from parametric uncertainties, nonlinearities (e.g., frictions) and external disturbances such as tyre self-aligning torque induced by varying road conditions. These factors make robust and high-performance control design particularly difficult. In this talk, the mathematical modelling of the SbW system is further explored and presented by an equivalent second-order dynamical system. Next, based on the derived simplified model of SbW system, a series of robust control schemes via sliding mode control (SMC) methodologies are introduced, such that the robustness, good tracking convergence, and excellent disturbance rejection ability of the closed-loop SbW control system can be well obtained. Further, novel SMC-based yaw stability control schemes including upper and lower controllers are developed for SbW vehicles to improve the vehicle manoeuvrability and yaw stability performance. Hardware-in-the-loop and vehicle platforms are established, where fruitful real-time experiments are presented in support of the remarkable performance and effectiveness of the proposed schemes. This talk also discusses practical challenges and opportunities in bridging the gap between academic research and industrial implementation of advanced SbW control technologies.