Robust Reliable Control for Uncertain Vehicle Suspension Systems With Input Delays

Synthesis of control design is an essential part for vehicle suspension systems. This paper addresses the issue of robust reliable H-infinity control for active vehicle suspension system with input delays and linear fractional uncertainties. By constructing an appropriate Lyapunov-Krasovskii functional, a set of sufficient conditions in terms of linear matrix inequalities (LMIs) are derived for ensuring the robust asymptotic stability of the active vehicle suspension system with a H-infinity disturbance attenuation level gamma. In particular, the uncertainty appears in the sprung mass, unsprung mass, damping and stiffness parameters are assumed in linear fractional transformation (LFT) formulations. More precisely, the designed controller is presented in terms of the solution of LMIs which can be easily checked by MATLAB-LMI toolbox. Finally, a quarter-car suspension model is considered as an example to illustrate the effectiveness and applicability of the proposed control strategy.