A Robust H-infinity Control Approach of Uncertain Tractor Trailer System

Abstract

This paper proposes a robust H-infinity control strategy for a differential drive Tractor with a single Trailer unit. This articulated vehicle being a complicated non holonomic system, the number of control inputs is less compared to the number of generalized coordinates. A linearized nominal model for this system is obtained by combining the kinematics and dynamics. A robust H-infinity output feedback control is designed using mu synthesis for the nominal plant when subjected to model uncertainties in unstructured form and output disturbances. Analysis on the robust uncertain closed-loop system is performed in both time and frequency domains. The simulation results indicating satisfactory stability and performance are presented. The step response and reference tracking are also found to be satisfactory.

Keywords:

• Disturbance rejection
• H-infinity
• Non-holonomic systems
• Robust control
• Tractor trailer systems
• Wheeled mobile robots

Additional information

Notes on contributors

A. Dolly Mary

A. Dolly Mary received the B. E degree in 1996 from the Department of Electrical Engineering, Thiagarajar College of Engineering, Madurai, Tamilnadu. She then received the M.Tech(Instrumentation &Control) degree from National Institute of Technology, Calicut, Kerala. She is serving as Assistant Professor in Electrical under Directorate of Technical Education, Govt. of Kerala and is currently pursuing Ph.D degree from National Institute of Technology, Calicut, Kerala. Her research interests include stabilization, disturbance rejection and robust control of multivariable systems. E-mail: [email protected]

Abraham T. Mathew

Abraham T. Mathew, born in 1959, earned his Ph.D in Control Systems from Indian Institute of Technology, Delhi in 1996. He is now working as the Professor in Electrical Engineering in the National Institute of Technology Calicut, Kerala, India. He is the member of IEEE, Fellow of the Institution of Electronics and Telecommunication Engineers, and Life Member of the Indian Society for Technical Education. He is currently engaged in research applied to the areas of robust control in industrial drives, power systems and process control, specifically in the research of control of articulated vehicles for robust tracking. Dr Abraham is also actively engaged in the study of the cybernetics and informatics applied to the Indian higher technical education in the context of academic globalization. E-mail: [email protected]

Jeevamma Jacob

Jeevamma Jacob is a Professor with the Department of Electrical Engineering, National Institute of Technology, Calicut, Kerala, India. She received the B.Tech degree in Electrical Engineering in 1983 from the University of Kerala, India and M. Tech(Instrumentation & Control) degree in 1985 from National Institute of Technology, Calicut (formerly REC, Calicut under University of Calicut), Kerala, India. She received the Ph.D (Control Systems) degree in 1994 from Indian Institute of Technology, Bombay, India.

Her areas of interest include robust multivariable controller design aspects extended to the areas of power systems, process control, digital control and biomedical engineering. She has published several papers in her areas of interests. Dr. Jeevamma Jacob is a life member of Indian Society for Technical Education. E-mail: [email protected]