Robust Output-Feedback Based Fault-Tolerant Control of Active Suspension with Finite-Frequency Constraint★★This work is partly supported by National Natural Science Foundation of China(Grant nos. 51205058, 51375086, 61403252), and Jiangsu Province Science Foundation for Youths, China(Grant no. BK20140634),the Foundation of Education Office of Guangxi Province of China (Grant no. KY2015YB101), the Fundamental Research Funds for the Central Universities and Jiangsu Postgraduate Innovation Programm (Grant no. KYLX-0102).

In this paper, the H∞ fault-tolerant control (FTC) problem of active suspensions with finite-frequency constraints is investigated. A full-car model is employed in the controller design such that the heave, pitch and roll motions can be simultaneously controlled. Both the actuator faults and external disturbance are considered in the controller design. As the human body is more sensitive to the vertical vibration in 4-8Hz, robust H∞ control with finite frequency constraints is designed. From the practical perspective, a robust dynamic output-feedback controller with fault tolerant ability is proposed, while other performances such as suspension deflection and actuator saturation are also considered. Compared with passive suspension, the performance of the proposed controller is more effective, especially in 4-8 Hz range.