Title: Nonlinear vehicle active suspension system control method based on the extended high gain observer
Authors: Qinghua Meng; Bingji Li; Chuan Hu
Addresses: School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, China ' School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou, Zhejiang, 310018, China ' Department of Mechanical Engineering, University of Texas at Austin, Austin, TX 78712, USA
Abstract: In order to reduce the number of sensors used in the vehicle active suspension system and improve the ride comfort and handling stability, this paper proposes a novel vehicle active suspension control approach based on an extended high gain observer (EHGO) approach. Firstly, for facilitating the controller design, the under-actuated active suspension dynamic model is transferred to a fully- actuated system dynamic model. Then the EHGO is constructed to estimate the unknown states and uncertainties according to the state functions of the active suspension control system. An output feedback controller based on EHGO is designed to improve the vertical ride comfort and handling stability of the active suspension. Furthermore, the closed-loop system is analysed to prove the boundedness of all the states. And the EHGO approach is proved to stabilise the active suspension by Lyapunov stability analysis also. Simulation and experiment results verify the effectiveness of the designed controller.
Keywords: active suspension; extended high gain observer; under-actuated system; Lyapunov stability analysis; nonlinear control; uncertain disturbance; output feedback control; quarter-car suspension dynamic model; closed-loop analysis; sliding mode control.
International Journal of Vehicle Design, 2023 Vol.91 No.4, pp.303 - 321
Accepted: 08 Jun 2021
Published online: 01 Jun 2023 *