Title: Higher order sliding mode-based robust stabilisation of fluid-flow model of TCP/AQM scheme

Authors: P. Baburaj; Shyam Kamal; Bijnan Bandyopadhyay

Addresses: IDP in Systems and Control Engineering, IIT Bombay, Powai, Mumbai-400076, India ' IDP in Systems and Control Engineering, IIT Bombay, Powai, Mumbai-400076, India ' IDP in Systems and Control Engineering, IIT Bombay, Powai, Mumbai-400076, India

Abstract: This paper deals with the stabilisation of TCP/AQM scheme from robust control theory perspective. A higher order sliding mode-based controller for the robust stabilisation of indeterminate system is proposed. Fluid-flow model of TCP-queue dynamics proposed in literature is a continuous uncertain system having matched and unmatched uncertainties in both system and input matrices. A novel sliding surface is designed with the aid of quadratic Lyapunov function with constant Jacobian matrix of coefficients in a special form. A second order sliding mode (super twisting) control law is synthesised which gives robustness with respect to matched uncertainties and at the same time reduces the chattering effect due to the continuous nature of the algorithm. The system is exponentially stabilised and the simulation results justify the efficacy of the proposed controller.

Keywords: higher order SMC; sliding mode control; TCP/AQM scheme; stabilisation; matched uncertainty; unmatched uncertainty; robust control; controller design; active queue management; AQM; transmission control protocol; TCP; fluid flow modelling; queue dynamics; simulation.

DOI: 10.1504/IJAAC.2014.061651

International Journal of Automation and Control, 2014 Vol.8 No.1, pp.17 - 31

Received: 09 Nov 2012
Accepted: 11 Nov 2013
Published online: 30 Jun 2014 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article