Assessment of Ride Comfort Enhancement in a Full Vehicle Active Suspension System Using Sliding Mode and Fuzzy Logic Control

Abstract

Vehicle suspension systems play a crucial role in ensuring ride comfort, stability, and safety under varying road conditions. While conventional passive suspensions offer limited adaptability, active suspension systems dynamically regulate actuator forces to counteract road-induced disturbances and improve overall performance. This paper introduces and comparatively evaluates two control strategies, sliding mode control and fuzzy logic control, for a full-vehicle active suspension system, aiming to achieve vibration suppression and ride comfort enhancement. Comprehensive simulations were performed in MATLAB/Simulink environment under three severe deterministic road-disturbance profiles with amplitudes ranging from −15 cm to +20 cm. The results demonstrate that both controllers effectively suppress full-vehicle vibrations under challenging road disturbances. Using SMC as the comparative reference, FLC achieved up to a 69.5% reduction in maximum vertical displacement and a 97.5% reduction in peak vertical acceleration, while maintaining a steady-state tracking error below 0.89 cm and comparable control effort. The study’s key contribution lies in demonstrating the superior vibration-suppression and ride-comfort performance of FLC relative to the implemented SMC in a full-vehicle active suspension system.. The large reduction in peak acceleration is mainly associated with the smoother control action of FLC compared with the switching-induced acceleration fluctuations of the implemented SMC. The main contribution of this study is a systematic comparative assessment of decentralized SMC and FLC under identical coupled full-vehicle suspension dynamics and severe asymmetric road disturbance.