Continuous Integral Sliding Mode control and Implementation of Super Twisting Control

Bijnan Bandyopadhyay Indian Institute of Technology Jodhpur India

Abstract:

The talk will be on a new algorithm developed by the speaker on continuous sliding mode based on integral sliding mode control (ISMC) where the discontinuous part of the ISMC is replaced by continuous control. It is shown that the well known super twisting control (STC) which replaces the discontinuous part of the ISMC acts as a disturbance observer and hence cancels the matched disturbance. As the overall controller is continuous, the proposed method is advantageous over the existing integral sliding mode control, which has a discontinuous term. Also from the practical implementation point of view, in particular for mechanical systems, discontinuous term will result in chattering which is very much undesirable. Some implementation results on a practical system and its superiority will be also discussed.
In the second part of the talk, an output feedback stabilization of perturbed double integrator systems using super twisting control (STC) will be presented. It will be shown that when STC is implemented based on super twisting observer (STO) then it is not possible to achieve second order sliding mode (SOSM) using continuous control on the chosen sliding surface. Two methodologies are proposed to circumvent the above mentioned problem. In the first method, control input is discontinuous which may not be desirable for practical systems. In second method continuous STC is proposed based on higher order sliding mode observer (HOSMO) which achieves SOSM on the chosen sliding surface. For simplicity, we are considering here only the perturbed double integrator, which can be generalized for an arbitrary order. Some Numerical simulations and experimental validation will be also presented to show the effectiveness of the proposed method.


Brief Bio:

Bijnan Bandyopadhyay received his B.E. degree in Electronics and Telecommunication Engineering from Bengal Engineering College(presently Indian Institute of Engineering Science and Technology shibpur), University of Calcutta, Calcutta, India in 1978, and Ph.D. in Electrical Engineering from IIT Delhi, India in 1986. In 1987, he joined the Systems and Control Engineering group, IIT Bombay, India, as a faculty member, where he has served as Chair Professor during 2015 ‐2021. Since 2022 he is serving as Visiting Professor at IIT Jodhpur. In 1996, he was with the Lehrstuhl fur Eleck ‐trische Steuerung und Regelung, RUB, Bochum, Germany, as an Alexander von Humboldt Fellow. He was awarded Distinguished Visiting Fellow by the Royal Academy of Engineering, London in 2009 and 2012. Professor Bandyopadhyay is a Fellow of the Indian National Academy of Engineering, National Academy of Sciences, Indian Academy of Sciences and Indian National Science Academy. He has in excess of 450 publications which include monographs, book chapters, journal articles, and conference papers. He has guided 42 Ph.D. theses at IIT Bombay. His research interests include the areas of multirate output feedback based discrete ‐time sliding mode control, event ‐triggered sliding mode control, and nuclear reactor control. Prof. Bandyopadhyay served as Co ‐Chairman of the International Organization Committee and as Chairman of the LocalArrangements Committee for the IEEE ICIT, Goa, India, in 2000. He also served as one of the General Chairs of the IEEE ICIT conference, Mumbai, India in 2006. Prof. Bandyopadhyay has served as General Chair for IEEE International Workshop on VSSSMC, Mumbai, 2012. He has served as Associate Editor of IEEE Transaction on Industrial Electronics, Technical Editor of IEEE/ASME Transaction on Mechatronics and Associate Editor of IET Control Theory and Applications. Prof. Bandyopadhyay has been awarded the IEEE Distinguished Lecturer of IEEE IES society in 2019. Professor Bandyopadhyay is Life Fellow of IEEE.