Semi-active roll stability control system using electro-hydraulic actuators integrated with rollover warning device

Roll stability is essential for vehicle safety, particularly during high-speed maneuvers, low-traction conditions, or exposure to crosswinds. This paper presents a semi-active roll stability control system for passenger vehicles, integrating a PID-controlled electro-hydraulic actuator with a rollover warning device. A dual-layer architecture is proposed: the lower layer implements a roll stabilization controller that activates only when lateral acceleration or roll angular acceleration exceeds defined thresholds, while the upper layer provides early driver alerts through a multi-stage warning interface. The system is developed using a refined half-car model and validated through MATLAB/Simulink simulations under ISO 3888 and ISO 4138 standard driving scenarios. Results show that the proposed active PID system reduces roll angle and roll angular acceleration by up to 57% and 62%, respectively, compared with the passive system. Additionally, the semi-active variant maintains comparable performance with 45%–54% reduction in roll dynamics while consuming significantly less energy due to conditional controller engagement. The rollover warning system accurately classifies risk levels with minimal false alarms, and peak sound intensity remains below 5 dB in the active model versus 20 dB in the passive case. The framework demonstrates robust performance at speeds up to 120 km/h and vehicle loads up to 3000 kg, offering a practical and energy-efficient solution for enhancing vehicle stability in real-time applications.