Prescribed performance fast terminal sliding mode control for vibration suppression in hydraulic active seat suspension systems

Purpose This paper aims to develop a prescribed performance fast terminal sliding mode control (SMC) strategy for active seat suspension systems under road disturbances and lumped uncertainties. Design/methodology/approach A hierarchical control architecture is developed, in which a prescribed performance framework is integrated with fast terminal SMC to generate the desired actuator force for vibration suppression, while cascaded proportional-integral-derivative controllers are used for hydraulic force tracking and spool-valve regulation. Numerical simulations are conducted under ISO C-class and ISO D-class road excitations. Findings The proposed controller achieves the best vibration attenuation performance among the compared methods. The maximum seat displacement and acceleration are limited to 0.72 mm and 0.08 m/s2 under ISO C roads and 0.91 mm and 0.10 m/s2 under ISO D roads. Originality/value This study presents a novel integration of prescribed performance control and fast terminal SMC, providing enhanced ride comfort and robustness for active seat suspension systems operating in uncertain road environments.