Robust finite-frequency H∞ control of full-car active suspension

Abstract In this paper, the finite-frequency H ∞ control problem of active suspensions is investigated. In view of the human body is much sensitive to the vertical vibrations between 4 and 8 Hz, a robust finite-frequency state-feedback H ∞ controller is introduced to suppress the sprung vibration in the concerned frequency range. In order to simultaneously control the vehicle heave, roll, and pitch motions, a full-car suspension model is adopted. Suspension parameter uncertainties, actuator saturation, and suspension deflection constraints are all considered in the model, and a robust controller is designed to handle the parameter uncertainties and achieve the prescribed H ∞ performance. Simulation with different road conditions and parameter uncertainties are performed and the results illustrate the effectiveness of the proposed controller.