Adaptive Sliding Mode Control for Vehicle Active Anti-Roll System Based on Property Adjustable Barrier Function

The active anti-roll system is capable of rapidly applying a counter roll torque to the vehicles when a roll tendency occurs, suppressing the degree of body roll and maintaining vehicle stability. However, the anti-roll system of a vehicle is a complex nonlinear system, where modeling errors, real-time changes in vehicle parameters, and uncertainties from external disturbances may affect its performance. Sliding mode control (SMC) has been widely applied in various fields owing to its effectiveness in handling the aforementioned issues. Nonetheless, conventional SMC requires knowledge of upper bound of disturbances, and the controller gain is typically set higher than the upper bound of disturbances to ensure convergence of tracking errors. To address this issue, the barrier function adaptive sliding mode control (BFASMC) is introduced, which can quickly converge the sliding variable to a predetermined domain without the need to know the upper bound of disturbances, and it can also avoid excessive actuator outputs. Based on this, a novel property adjustable barrier function adaptive sliding mode control (PABFASMC) strategy has been set to adapt to the application of the actuators. It is possible to balance the convergence time of sliding variable and control input, while also avoiding singularity problems of the control law. Co-simulation was conducted using the MATLAB/Simulink controller model and the CarSim vehicle model to evaluate the performance of PABFASMC. The experimental results demonstrate that the developed controller exhibits the aforementioned performance, while also proving the effectiveness of the active anti-roll system in enhancing vehicle stability and ride comfort.