Table of Contents
Journal of Nonlinear Dynamics
Volume 2014, Article ID 489364, 10 pages
http://dx.doi.org/10.1155/2014/489364
Research Article

Dynamic Sliding Mode Control Design Based on an Integral Manifold for Nonlinear Uncertain Systems

1Centre of Advanced Studies in Telecommunications (CAST), COMSATS, Park Road, Chak Shahzad, Islamabad 44000, Pakistan
2Department of Electronic Engineering, MAJU, Express Highway, Kahuta Road, Islamabad 44000, Pakistan
3Department of Engineering, University of Pavia, Pavia, Italy

Received 27 May 2013; Revised 21 October 2013; Accepted 23 October 2013; Published 2 January 2014

Academic Editor: Huai-Ning Wu

Copyright © 2014 Qudrat Khan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

An output feedback sliding mode control law design relying on an integral manifold is proposed in this work. The considered class of nonlinear systems is assumed to be affected by both matched and unmatched uncertainties. The use of the integral sliding manifold allows one to subdivide the control design procedure into two steps. First a linear control component is designed by pole placement and then a discontinuous control component is added so as to cope with the uncertainty presence. In conventional sliding mode the control variable suffers from high frequency oscillations due to the discontinuous control component. However, in the present proposal, the designed control law is applied to the actual system after passing through a chain of integrators. As a consequence, the control input actually fed into the system is continuous, which is a positive feature in terms of chattering attenuation. By applying the proposed controller, the system output is regulated to zero even in the presence of the uncertainties. In the paper, the proposed control law is theoretically analyzed and its performances are demonstrated in simulation.