Analysis and experiment of time-delayed optimal control for vehicle suspension system

In this paper, the performance of vehicle suspension system under time-delayed optimal control is investigated. The effect of time delay on control stability of the active suspension system is discussed. The mathematical simulation is used to verify the correctness of the stable interval obtained by differential equation theory for linear systems with constant coefficients and time delay. In order to keep the stability of the system, time-delayed optimal control is designed through the method of state transformation and optimal control theory. The results show that the control strategy could not only guarantee the stability of the system regardless of the variation on control time delay, but also improve the performance of the suspension system. Additionally, influence of the designed active time delay on the amplitude of sprung mass acceleration, suspension deflection, rode holding are analyzed to provide guidance for its further practical engineering application. Vibration control experiments of the active suspension system under harmonic excitation with time-delayed optimal control are figured to compare with simulations. It is seen that the designed time-delayed optimal control strategy has the effectiveness and advantage. (C) 2019 Elsevier Ltd. All rights reserved.