Adaptive output-feedback control for a class of nonlinear systems with actuator failures and input quantisation

ABSTRACT

In this paper, an adaptive output feedback control technique is proposed for a class of nonlinear systems with unknown parameters, unknown nonlinear functions, quantised input and possible actuator failures up to infinity. A modified backstepping approach is proposed by the use of high-gain K-filters, hyperbolic tangent function property and bound-estimation approach to compensate for the effect of possible number of actuator failures up to infinity, input quantisation and unknown nonlinear functions. It is proved both mathematically and by simulation that with the proposed controller, all the signals of the closed-loop system are globally bounded despite of input quantisation, unknown nonlinear functions and possible number of actuator failures up to infinity.

KEYWORDS:

• Adaptive control
• actuator failures
• nonlinear systems
• output feedback
• quantisation

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the NSF of China [grant number 61273141], [grant number 61433011]; NSFC [grant number 61673038], [grant number 61433011].