Adaptive dual-layer super-twisting control and observation

ABSTRACT

In this paper, a super-twisting-like structure with adaptive gains is proposed. The structure is parameterised by two scalar gains, both of which adapt, and by an additional time-varying term. The magnitudes of the adaptive terms are allowed to both increase and decrease as appropriate so that they are as small as possible, in the sense that they do not unnecessarily over-bound the uncertainty, and yet are large enough to sustain a sliding motion. In the paper, a new time varying gain is incorporated into the traditional super-twisting architecture. The proposed adaption law has a dual-layer structure which is formally analyzed using Lyapunov techniques. The additional term has the effect of simplifying the stability analysis whilst guaranteeing the second-order sliding mode properties of the traditional super-twisting scheme.

KEYWORDS:

• sliding modes
• adaptation
• super-twisting control

Acknowledgements

We would the like to thank the reviewers of the original submission for their technical suggestions to help improve the paper.

Disclosure statement

No potential conflict of interest was reported by the authors.