Active Suspension of Output Feedback Robust Control Based on LMI Approach

Traditionally automotive suspension designs have been a compromise between the three conflicting criteria of road holding, load-carrying and passenger comfort. Active and semiactive suspension control methods have been considered as ways of increasing the freedom one has to specify independently the characteristics of load carrying, handling and ride quality. Consequently, these control methods have been enthusiastically investigated in the past decades. In this paper, active suspension control based on LMIs, including H∞ control and mixed H₂/H∞ synthesis has been developed in this paper. The simulation results demonstrate that robust control method can suppress disturbance from road inputs, thus improving the ride comfort and maintaining the good road handling. The mixed H₂/H∞ synthesis can provide both the robustness of H∞ control and the better performance of H₂ (LQR) method.