Robust guaranteed-cost control with regional pole placement of active suspensions

To alleviate mechanical parts fatigue and provide a comfortable ride for passengers, car mechanics require desired dynamic behavior of car suspensions. This paper suggests state feedback controllers that, with system uncertainties, guarantee the closed loop system satisfying the desired pole region, thus achieving satisfactory oscillation damping and settling time, and having the guaranteed cost performance simultaneously. A state feedback controller is applied to the design of an active suspension model for a quarter-car vehicle. The controller's parameters are obtained using the linear matrix inequalities optimization, also allowing considering the model uncertainty represented by a norm-bounded structure. Simulations are carried out taking into account the presence of uncertain parameters. The results are shown to be better than the classical linear quadratic regulator.