A New Method for Adaptive Control of Non-Linear Plants Using Type-2 Fuzzy Logic and Neural Networks

Abstract

We describe in this paper adaptive model-based control of non-linear plants using type-2 fuzzy logic and neural networks. First, the general concept of adaptive model-based control is described. Second, the use of type-2 fuzzy logic for adaptive control is described. Third, a neuro-fuzzy approach is proposed to learn the parameters of the fuzzy system for control. A specific non-linear plant was used to simulate the hybrid approach for adaptive control. The specific plant was also used as test bed in the experiments. The non-linear plant that was considered is the “Pendubot”, which is a non-linear plant similar to the two-link robot arm. The results of the type-2 fuzzy logic approach for control were good, both in accuracy and efficiency.

Keywords:

• Type-2 fuzzy logic
• neural networks
• adaptive control
• pendubot

Acknowledgements

We would like to thank the Research Grant Committee of CONACYT (Under Grant 33780-A) for supporting this research work.

Notes

Patricia Melin holds a Ph.D. in Computer Science from Kensington University, USA, a Professional Certificate in Microcomputer Engineering from the University of California in San Diego (UCSD), and a Bachelor Degree in Biochemical Engineering from Tijuana Institute of Technology. Her current research interests are in neural networks, fuzzy logic, control of non-linear dynamical systems and mathematical modeling and simulation of complex engineering systems. She has published more than 120 technical papers in journals, edited books and conference proceedings. She has received several awards in recognition of her many academic achievements. She has been a member of IEEE Control Systems Society since 1998, a member of IEEE Neural Networks Society since 2002, and a member of New York Academy of Sciences since 1999, and has been a Technical Reviewer for several Conferences. She is a full-time professor at Tijuana Institute of Technology since 1998, and has work in applied research projects with the industry. Also, she has directed and participated in several research projects in collaboration with well-known universities and research institutes. She is author of the book “Modelling, Simulation and Control of Non-Linear Dynamical Systems” published by Taylor and Francis, Great Britain in January 2002, co-author of the book “Soft Computing for Control of Non-linear Dynamical Systems” published by Springer-Verlag, Germany in January 2001, and co-author of the book “Soft Computing and Fractal Theory for Intelligent Manufacturing” published by Springer-Verlag, Germany, in January 2003.

Oscar Castillo is a full-time professor in the Computer Science Department of Tijuana Institute of Technology since 1985. He holds a Ph.D. in Computer Science from Kensington University, USA, a Master Degree in Applied Mathematics from National Polytechnic Institute of Mexico, and a Bachelor of Science Degree in Electrical Engineering from Tijuana Institute of Technology. He is a member of IEEE Neural Networks Society, IEEE Fuzzy Systems Technical Committee, NAFIPS and New York Academy of Sciences. His main research areas are fuzzy logic, neural networks, genetic algorithms, robotics and control of dynamical systems. He has received several awards for his achievements in research and teaching during his work at Tijuana Institute of Technology. He has received many research grants from government and industry to direct his many research projects. He has also collaborated with researchers from other countries in several projects of great importance. He has over 130 technical papers in proceedings, journals and edited books. Because of his many contributions he has been elected to the Editorial Board of several journals in computational intelligence. He is author of the book entitled “Soft Computing for Control of Non-Linear Dynamical Systems” published by Springer-Verlag, Germany, in January 2001, co-author of the book “Modelling, Simulation and Control of Non-Linear Dynamical Systems” published by Taylor and Francis, Great Britain, in January 2002, and author of the book “Soft Computing and Fractal Theory for Intelligent Manufacturing” published by Springer-Verlag, Germany, in January 2003.