Distributed prescribed performance control for consensus output tracking of nonlinear semi-strict feedback systems using finite-time disturbance observers

ABSTRACT

The distributed consensus output tracking problem is dealt with for a class of nonlinear semi-strict feedback systems in the presence of mismatched nonlinear uncertainties, external disturbances and uncertain nonlinear virtual control coefficients of the subsystems. The systems are under a directed communication graph, where the leader node is the root. The controller is designed in a backstepping manner, and the dynamic surface technique is adopted to avoid direct differentiation. At each step of virtual controller design, a prescribed performance controller is constructed to achieve prescribed transient performance so that the system states remain in the feasible domain. Then each virtual controller is enhanced by a finite-time disturbance observer which estimates the disturbance term in a finite-time. The properties of the control system are analysed theoretically. It is clarified that the prescribed performance control technique ensures that the system signals stay in the feasible domain, whereas sufficiently small ultimate control errors can be achieved by the finite-time disturbance observers. Finally, the performance of the proposed methods is confirmed by numerical studies.

KEYWORDS:

• Finite-time disturbance observer
• backstepping control
• cooperative control
• semi-strict feedback system
• prescribed performance control

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Zi-Jiang Yangi http://orcid.org/0000-0003-3588-9906

Additional information

Funding

This work was supported by JSPS KAKENHI Grant Number JP16K06408.

Notes on contributors

Zi-Jiang Yang

Zi-Jiang Yang was born in 1964. He received the Dr. End. degree from Kyushu University, Fukuoka, Japan in 1992. He was an Assistant Professor from 1992 to 1996, and an Associate Professor from 1996 to 2001, with Kyushu Institute of Technology. From 2001 to 2009, he was an Associate Professor with Kyushu University. Since 2009, he has been a Professor with the Department of Mechanical Systems Engineering, Ibaraki Univesity, Ibaraki, Japan. His research interests include system identification and nonlinear system control.